History of AO VET – The First 40 Years by AO Foundation

of A OVET irst 4

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Hist ory The F

Jörg A Auer Ortrun Pohler Martina Schlünder Ferenc Kása Gerhilde Kása Marvin Olmstead Björn von Salis Gustave E Fackelman

Since mythological, prehistoric times animals have been a significant part of human culture and civilization. Historically, it was an essential step forward in the development of mankind, when human beings learned how to tame, breed and domesticate animals. A wooden Egyptian cat sculpture (Fig 1) and a depiction of a horse transporting the sun (Fig 2) demonstrate the artistic creation of animal sculptures in ancient times. Throughout history animals have played different roles and have had different functions: they were adored, used for work, food and clothing, and utilized for their specific skills, which were often considered superior to those of human being. However, they have also been misused and neglected. The history of AOVET tells of the unique development of systematic orthopedic operative fracture treatment in the veterinary medical discipline on the basis of—and in analogy to—the methodology developed by AO/ASIF to treat systematic osteosynthesis in human patients. It shows that large and small animal veterinary surgeons and ultimately their patients profited from the clinical experience gained in the treatment of human patients.

Fig 1 Ancient Egyptian cat, 2700 years old (wood) (Museum Rietberg, Zurich, Switzerland).

Fig 2 Trundholm Sun Chariot, Denmark, 3400 years old. The horse and the wheels create the association of the rapid motion of the sun.

Table of contents Timeline of AOVET

1 Setting the field 2

How AOVET started

3 The Waldenburg Circle

4 Osteosynthesis in small animals 5

Maxlie the horse

6 Institutionalizing the Waldenburg Circle: the foundation of AOVET and pioneering work

7 The hop over “the big pond”

8 Spreading the word—AOVET Center Waldenburg 9

Consolidating the achievements of the AOVET founders

10 Special events 11 Epilogue List of AOVET Presidents References

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1â&#x20AC;&#x201A; Setting the Field

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1 Setting the Field

Traditionally, in recent centuries in rural settings veterinarians were mainly occupied with the treatment of horses and cattle, which were mostly working and/or food-producing animals. If necessary they also took care of “small animals”, such as cats and dogs, as well as other domesticated animals. Expensive treatments were not afforded to cats and dogs as replacement was so natural and inexpensive. In the midnineteenth century the disappearance of horses as working animals and the advent of industrialization with increasing introduction of machines, such as tractors, had a strong impact on veterinarians not only regarding their professional identity but also economically [1–9]. Since then, horses have been primarily used for pleasure riding or various sports activities, such as racing, dressage, and show jumping, while cattle have been kept as food and fiber-producing animals. At the same time, particularly in the growing cities, small animals increased in large numbers. These animals were kept by their owners as pets, the most popular being cats and dogs [10, 11]. The emotional attachment to these animals resulted in the increasing commercialization of a pet’s life. Pets might have been economically unimportant for their owners but they had an economic value for breeders, the pet food industry, and for veterinarians. While at the beginning of the twentieth century small animal practitioners could be found only in small numbers and only in large cities, their numbers started to increase during the 1950s and 1960s and now dominate veterinary medicine and surgery [1, 2, 12]. Because pet owners have been ready to spend an increasing amount of time and money for their beloved, emotionally highly valued animal companions, veterinarians have been able to apply more demanding treatments.

The drastic modification of their patient population from large animals to small animal pets confronted veterinarians with new treatment regiments. Traditionally veterinarians had been trained on the basis of the functional pragmatism that ruled the lives of working animals [13–16]. In the context of pet ownership, however, the veterinarian’s mission changed. It was no longer about curing inexpensively or otherwise killing the sick animal. The treatment of pets closely followed the model of human medicine instead, something that was increasingly expected by pet owners. Veterinarians thus switched from a functional pragmatism to an “economy of love” as a basis for their work. This change, however, confronted veterinarians with the fact that they often did not know how to treat an animal according to human medical practice.

1 Setting the Field

Insufficiency in operative fracture treatment These problems were of particular relevance for veterinary surgery, especially in the field of trauma and orthopedic surgery. Modernization and industrialization had led to a rapid increase in the numbers of motor vehicles and, consequently, to growing numbers of animals injured in traffic accidents [19]. The injuries they suffered were more complicated than those caused by a simple accident, fall, or kick by another animal. Thus, the veterinarians were challenged quantitatively with more fractured bones and qualitatively with more complicated fractures. Whereas previously the injured animals would have been euthanatized, now their owners expected effort to be made to heal and save the lives of their pets. In the 1950s and 1960s, however, veterinarians’ knowledge and treatment options for dogs, cats, and horses with broken bones were limited, although certain adoptions from human trauma surgery had been made [17–24]. For operative fracture treatment in small animals, the most popular approach in Germany and Switzerland (as well as in other countries) was intramedullary nailing corresponding to the Küntscher technique (Fig 3a–d) [25, 26] and modifications thereof, like the Rush-pin application and the stacked pin nailing. The use of these elegant but somewhat tricky surgical methods was relatively widespread during that era, even though they had their limitations. In dogs intramedullary nailing was more demanding than in humans, since the cortex of the dog bone is thinner and more brittle, the diameter of the medullary space more diverse than in humans. Instability and subsequent complications, such as nonunions, pseudarthroses, and implant failures, were frequently the result. Also, the anatomy of long bones varies considerably among different breeds, making this technique difficult to standardize [27]. One of the German small animal surgeons of the 1950s, Dr Heinrich Müller, who studied intramedullary nailing techniques, blamed a blatant lack of accompanying scientific research and the ensuing lack of knowledge flow between the fields of human and animal fracture treatment for the poor results [28, 29]. Joint and near-joint fractures are difficult to stabilize with nailing techniques or with pins and cerclage techniques, except for some special methods that have been developed over time. Conservative fracture care with plaster of Paris casts and bandages as practiced in human medicine is rarely suitable for small animals, since the

patients usually destroy such applications. Thus, fracture treatment in small animals during the 1950s and 1960s was problematic and had many shortcomings.

Fig 3a–d a Mrs Willenegger’s dog named Kai. b Suffered a mid-shaft femoral fracture. c In the 1940s, Drs Knoll and Willenegger assisted Dr. Jacques Jenny insert a Küntscher nail into the medullary cavity, which led to complete healing of the fracture. d 14-week follow-up x-ray after complete fracture healing with the nail still in place (left) and x-rays 2 weeks later after nail removal (right).

1 Setting the Field

In large animals operative fracture treatment was extremely difficult, although occasionally attempts were undertaken. Dieter Prieur refers to an early case [27] from 1891, in Cairo, Egypt, where a city police horse that had suffered a broken jaw was successfully treated with a drilled wire suture (cerclage). After 10 months the horse was back to work. A publication in 1966 [30] reports on the osteosyntheses of fractures of the lower jaw in cattle by means of compression-plate applications, carried out in collaboration by a veterinary surgeon together with an experienced human surgeon. A brief look at human trauma surgery in the mid-1950s indicates that at this time many unsolved problems existed in the operative treatment of fractures. Many trauma surgeons characterized their field as the “Cinderella of modern surgery” [31, 32]. Trauma surgery and fracture care had not participated in the triumph of modern surgery in the late nineteenth and early twentieth centuries. One reason why fracture treatment was relatively unattractive to most surgeons was its conservative character. Most patients with fractured bones were treated with immobilizing techniques, such as plaster casts and traction. Operative fracture care was extremely demanding in terms of operative techniques, implant design and quality and asepsis. The associated risk of bone infection made it unsuitable for large-scale use. Complications occurred frequently but their reasons were rarely analyzed or understood. Only a few surgeons tried to make operative fracture care a viable option. Even in human fracture surgery not much systematic scientific research was conducted. Knowledge was usually based on personal experience of individual surgeons and not on larger systematic clinical or laboratory research. Aside from Gerhard Küntscher, who improved and expanded the intramedullary nailing technique, there were the esteemed surgeons Albin Lambotte and Robert Danis who applied their novel ideas to stabilize fractures with external transfixation devices and with screws and plates [33].

Systematic approach to osteosynthesis in human surgery developed by the AO group The breakthrough and spread of a systematic operative fracture treatment occurred with the founding of the Arbeits gemeinschaft für Osteosynthesefragen (AO) that took place on November 6, 1958, in Biel, Switzerland [1]. Based on private individual interest and driven by the search for improved and dependable osteosynthesis techniques, the five surgeons of the core group who initiated the formation of the AO (Maurice Müller, Martin Allgöwer, Hans Willenegger, Robert Schneider, and Walter Bandi) (Fig 4a–e) had met numerous times between 1952 and 1956 to exchange their experiences, concerns, and new concepts [33]. They concentrated increasingly on collaboration, systematic work, and the analysis of clinical problems. By 1957 they formulated essential preconditions for successful operative fracture treatment stressing the importance of a functional view of osteosynthesis. In December 1957 they decided on the formation of an “Association pour Osteosynthèse” [33, 34]. At an internal meeting in March 1958 they demonstrated and evaluated all osteosynthesis equipment available at that time. The results were disappointing and the five surgeons decided to develop their own instrument and implant systems and surgical methods for the different fracture types and orthopedic interventions. Professor Maurice Müller, the most highly motivated and most active of the group, presented an overview of the “aims and general principles of modern osteosynthesis in adults” that sounded almost like an AO program [44]. Among other aspects the following characteristic points were included: Aims: • Early postoperative mobilization and activation of near-fracture joints and muscles; this is very effective but must not be forced too much • Reconstruction of the anatomical conditions; this is a precondition for functional results

Basic Principles: • Continuity of asepsis from accident to healing; postoperative wound drainage; careful anatomical operation, reconstruction and reduction • The fractured area should be transformed into a stable block by the osteosynthesis • Where possible fragments should be set under compression for increased stability • Pseudarthroses tend to heal quickly under compression, but the source for the pseudarthroses should be detected and treated if required. The implant materials must be biocompatible

1 Setting the Field

The various aims and concepts were followed up meticulously, with astonishing momentum and personal engagement. To implement the agreed development of instruments and implants, Professor Müller visited Robert Mathys in spring of 1958 in his production company in Bettlach where he was working with stainless steel. Mathys started immediately to design and manufacture prototypes, so that the first samples of the 4.5 mm screws with the corresponding (round-hole) plates and implantation instruments were available already at the founding meeting in November of the same year. Thus, Mathys was the first manufacturer of AO implants and became the first exclusive producer of AO products (later to become Synthes products) and contributed substantially to the development of the equipment. The AO surgeons were highly successful because they approached operative fracture treatment on an unusually broad and systematic basis and, at a point in time, when important new techniques in various fields like metallurgy, physics, aseptic surgical techniques, and perioperative antibiotic management were developed and became available to solve major problems of bone surgery. They developed implants, instruments, surgical techniques, and after-care protocols simultaneously. They studied the biomechanics of the normal skeleton and of the injured and treated bones, and they investigated osteogenesis, and bone healing mechanisms under various conditions histologically and metabolically. In 1959 the AO Research Institute for Experimental Surgery was established in Davos through the particular initiative of

Fig 4a–e The principal founders of AO: (a) Martin Allgöwer, (b) Walter Bandi, (c) Maurice Müller, (d) Hans Willenegger, and (e) Robert Schneider.

Professor Martin AllgĂśwer and supported by the financial donations of the AO members. The Documentation Center for the clinical cases of the AO members was moved there, and a tissue culture laboratory was soon installed. This laboratory also addressed the question of metal toxicity and led to the early studies of biocompatibility of implant materials and their components by Dr Lotte Hulliger and Ortrun Pohler [35, 36]. Professor Herbert Fleisch led the AO Research Institute during the early years. His special research interests were bone biochemistry and metabolism, as well as bone pathology and the development of medications for bone disorders. From 1967 onwards Professor Stephan Perren led the Research Institute as its director and constantly expanded its facilities in addition to its organization, engagements, and the subjects of research at the highest level. He implemented biomechanical, biological, and mechanical testing and analyses, histological and clinical research, cell and organ culturing, and biocompatibility studies, as well as the development of implants and instruments. The AO Research Institute also provided enormous teaching and operative support for the annual Davos courses. The accumulated knowledge and expertise of the AO Research Institute contributed tremendously to the success of the AO concepts and the AO Foundation. After the Straumann Institute in Waldenburg was contacted by the AO in 1960 (see next chapter), it became instrumental in developing implant materials that possessed the required biocompatibility, corrosion resistance, and variability in mechanical properties [32, 33]. Along with other developments, the Straumann Institute became the second exclusive producer in 1962 [34â&#x20AC;&#x201C;36]. The collaboration of the surgeons with the producers, engineers, physicists, metallurgists, biologists, and scientists contributed to development and progress and provided specific research techniques. Also, the availability of antibiotics at that time and improved antiseptic management reduced the risk of infection and supported the surgical success. The AO, together with its producers, pursued a strategy of standardization and quality control of instruments and implants as well as teaching correct equipment handling and corresponding operative techniques. For this purpose, the AO established the Technical Commission (TK) in 1961 for the guidance, testing, and acceptance of new developments in AO surgical equipment and methods.

1 Setting the Field

In so doing, they had organized a system of quality control and assurance, many years before today’s required international quality-management standards (ISO). However, with the propagation of the “compression-osteosynthesis technique” where screws and plates created reduction of the fracture gaps and axial compression at the end of the bone fragments, the AO surgeons met with opposition from their colleagues because the common opinion then was that compression destroyed the bone. Another related controversy arose surrounding the phenomenon of “callus-free healing”, which was detected in connection with the stable osteosynthesis techniques. At that time it was generally accepted that callus formation should be interpreted as a sign of progressive bone healing. Thus, surgeons concluded wrongly that the missing callus with stable internal fixations indicated a lack of bone healing. The experimental clinical and histological research conducted by Professor Hans Willenegger (Hospital Liestal near Basel) and Professor Robert Schenk (University of Basel at that time) demonstrated that with sufficiently stabilized osteotomies primary direct bone healing occurs without callus formation [37, 38]. Stephan Perren showed with his strain gauge measurements on experimental compression osteosynthesis on sheep in combination with related histological investigations that no bone resorption occurred with the exerted compression [39]. These scientific findings, combined with the many documented successful clinical cases, soon convinced the surgical orthopedic community. Meticulous documentation and critical evaluation of the clinical cases, as well as learning from complications, were important milestones of the AO philosophy. The yearly spring and fall closed membership meetings and open scientific sessions provided a forum for information, exchange of experience, and coordinated clinical projects. The AO members obtained more and more requests from their colleagues who wanted the AO equipment for their own surgery. Since the operation techniques were subtle and the risks of probable complications high, the AO decided to sell the equipment only to surgeons who were well trained and attended a special instruction course. At the same time it was agreed with Dr Peter von Rechenberg of Synthes AG, Chur, that earnings from the sale of the surgical equipment would flow back into the research. In December 1960

the first AO course was offered in Davos with lectures and practical exercises using original implants and instruments on anatomical specimens. The Davos courses were then offered on an annual basis and have grown in numbers and diversity of their content. Additional courses expanded internationally. Corresponding teaching material was developed and continually updated including videotapes for practical exercises. The first AO manual with descriptions of the various operation techniques for typical fracture treatments and general introductory information was published in 1963 [40]. This was followed by a series of updated editions of AO manuals [41â&#x20AC;&#x201C;44] in different languages (the third edition contains sections on biomechanics, classifications of fractures, soft-tissue injuries, and other interesting topics [43]). The teaching, documentation, classification, interdisciplinary research, specific surgical equipment and methodology, and an international radius of action were the important cornerstones of the AOâ&#x20AC;&#x2122;s development. However, the essential element was an unusual willingness to cooperate and exchange information and experience, sustained by a sincere and wholehearted human attitude characterized by responsibility, honesty, and tolerance of each other. This specific characteristic of AO membership supported the formation of an AOVET organization, about a decade after its own founding. AO was generous in sharing its surgical methodology and scientific knowledge with the fledgling discipline of veterinary orthopedic surgery. In this way, a group of veterinary surgeons enabled to develop efficient and dependable osteosynthesis methods on a systematic basis for small and large animal fracture treatment. Some of the AO principles and equipment could be transferred directly to veterinary surgery, some of them needed adjustment and modification, and new solutions had to be developed as well. In addition, the veterinarians had to learn many of the general surgical preconditions and skills, which are standard procedures in the treatment of human patients. Moreover, the veterinarians had to undergo numerous experiences similar to those of the AO founders.

2â&#x20AC;&#x201A; How AOVET started

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2â&#x20AC;&#x201A; How AOVET started

Several fortunate coincidences led to the formation of the initial group of veterinarians, human trauma surgeons, and scientists that eventually resulted in the founding of AOVET. A horse shot dead When Dr BjĂśrn von Salis (Figâ&#x20AC;Ż5) was a teenager he was taken to the local horse races. In the middle of a race one of the horses fell with a broken leg and shot dead on the spot. This was a crucial experience for the young visitor and it led him to become a veterinarian. Von Salis told himself that such things could not be tolerated, and dedicated the rest of his life to finding solutions to this problem. When he worked as a senior veterinarian at the Equine Hospital of the University of Bern in the 1950s, he noticed how underdeveloped the facilities for equine surgery were. Neither adequate instruments nor surgical techniques were available for equine trauma surgery. Also, horses could not be anesthetized for longer than 30 minutes. At that time horses were exclusively anesthetized with intravenous chloral hydrate. Therefore, von Salis decided to first examine the problem of anesthesia. Veterinary anesthesia was more advanced in the UK, where Leslie Hall was starting to use halothane for inhalation anesthesia. Intrigued by this work, von Salis decided to go there and study these new techniques. After returning to Switzerland he introduced these techniques into the standard procedures at the Equine Hospital of the University of Bern and later published an article on equine anesthesia [45]. His second goal for improving equine surgery was the development of new transportation facilities for horses after an accident. Since horses were typically put to death humanely, little experience existed on how to transport an injured animal and what kinds of devices were needed to load an injured horse into a trailer, either in a standing or recumbent position. This challenged him to construct an ambulance vehicle equipped with an x-ray unit and first-aid facilities.

In the mid-1960s von Salis left the University of Bern and moved on to work in a small animal practice in Basel so that he could complete his specialization degree in small animal surgery and medicine. There he became friends with Ferenc (Feri) and Gerhilde (Geri) Kása, small animal veterinarians who practiced and lived in Lörrach near Basel on the German side of the Rhine river. Von Salis never forgot the need to look for adequate implants and instruments for trauma surgery in horses.

Fig 5 Björn and Cathrin von Salis during an AO function in Davos.

2 How AOVET started

Dr Guggenbühl’s huge dogs Before Dr August Urs Guggenbühl became the chief and general surgeon at the Hospital in Grenchen (near Solothurn) in 1957, he worked as chief resident at the Liestal Hospital under Hans Willenegger, one of the AO Founding Fathers, Guggenbühl was the youngest of the 13 AO founding members in 1958. Urs Guggenbühl was the proud owner of seven dogs (Irish Wolfhounds, a Great Dane, a Bordeaux Dane, a Mastiff, as well as a Greyhound) who used to accompany him almost everywhere in his Jaguar convertible (Fig 6). He was renowned for showing up with all of them in tow. Actually, he had never planned to have so many (and such huge) dogs. He had ended up with them by accident but he loved to live with them. Of course, Guggenbühl was in contact with the local veterinarian at that time but he was not impressed by the techniques and equipment used for fracture care in animals. Therefore, he started teaching the veterinarian the AO Principles of osteosynthesis. Occasionally, Guggenbühl himself carried out a surgical intervention with the veterinarian’s assistance.

Fig 6 Urs Guggenbühl in front of his house with four of his prize-winning giant dogs.

Afterward he discussed these animal cases with his AO colleagues. Willenegger, who knew about the veterinary activities in Waldenburg, introduced Guggenbühl to the veterinarians, which led to his engagement as a veterinarian teacher. An animal owner and engineer In 1954, Dr Fritz Straumann (Fig 7) and his father Professor Reinhard Straumann established a private research institute in Waldenburg (near Basel) to facilitate further development, investigation, and testing of watch-spring materials and watch-spring designs that the elder Straumann had invented. The spring metal alloys were sophisticated and their production processes required close attention and metallurgical expertise. Since Fritz Straumann was very interested in all natural sciences and technology, he expanded their research beyond the watch industry into other areas as well. The concept was to invest the earnings from their patents into their research institute. In 1960 Fritz Straumann was contacted by Willenegger, who was seeking assistanceto improve the material quality of AO implants because there were problems with the corrosion and failure of plates and screws. Ortrun Pohler (Fig 8) analyzed the defect implants and found that impurities and an insufficient composition of the stainless steel were the reason for the corrosion. The breaking of the implants was caused by material fatigue where a crack propagates with time through the material under alternating bending stresses (cyclic loading). Such critical local bending stresses can be generated under the load bearing of the patient, in cases where bony defects and instability of the osteosynthesis are present. With time this phenomenon was studied in depth [46]. Straumann developed of a stainless steel with high corrosion resistance and variable mechanical properties that were particularly suited for clinical applications. This material became the model for the internationally standardized implant steel that is currently used. Straumann volunteered to help to the AO surgeons, and was able to assist in the development of various techniques to resolve clinical biomedical problems.

Fig 7 Fritz Straumann giving an address during an AO function.

Fig 8 Ortrun Pohler a scientific member of AO and an AOVET member working on a publication.

2 How AOVET started

For example, he developed the first bone saw that was able to cut thin undecalcified embedded bone sections for histological microscopy. This provided bone histology with a technique to obtain a more detailed and realistic visualization of the microscopic bone structure and further understanding of bone remodeling and healing. Fritz Straumann was also a passionate horseman. He owned a number of horses and kept them at stables and an indoorriding arena close to a nearby castle called Bechburg (Fig 9), a place also used for occasional veterinary activities. Straumann also owned dogs (blood hounds and bassets). In 1967, when one of the dogs became sick, Fritz Straumann took it to Dr Christoph Uehlinger, a small animal practitioner in Basel, and there he met Björn von Salis.

Fig 9 Bechburg, near Waldenburg, the place where AOVET was founded.

2 How AOVET started

Getting together Christoph Uehlinger told von Salis about Straumann’s involvement in the development of instruments and implants for fracture care in humans, and von Salis immediately recognized that Straumann could be instrumental in solving his third problem concerning trauma surgery in horses: the design of appropriate instruments and implants. Von Salis helped treat Straumann’s dog and started visiting the dog and its owner at their home in Waldenburg. He had prepared himself very well for his first visit. He took his publications on horse anesthesia and a Dutch book by Verhaar on operative fracture management in large animals with him to Waldenburg [47]. In those days fracture treatment in horses was in its infancy. The two men got along very well from the start. Indeed, their first conversation lasted until 3:00 am in the morning. When von Salis asked Straumann at the end of their meeting if he could help him with the instrumentation problem, the engineer promised every kind of help and support, including the offer to use his laboratories. As a first step Straumann set his metallurgist, Dr Ortrun Pohler, to work on the “animal-project”. She was already experienced in the research and development of AO implants and was in close collaboration with the AO Research Institute in Davos. They agreed to meet every Wednesday afternoon at the Institute in Waldenburg to explore the conditions under which the AO techniques and equipment could be applied to fracture management in animals. Björn von Salis attempted to involve Christoph Uehlinger in the devlopment of implants for the veterinarians. When he declined, von Salis asked Feri and Geri Kása (Fig 10a–b) who jumped at the chance because they previously had a frustrating experience treating a radioulnar fracture without proper instrumentation and implants. A week later they joined Björn von Salis on his visit to Waldenburg as they were searching for more efficient internal fixation methods to overcome the limitations of the common nailing, pin, and cerclage techniques they were using so far. Although they had developed particular skills in nailing fractures in small birds (Fig 11a–c) [48], this was the start of intense work on veterinary osteosynthesis in large and small animals.

b Fig 10a–b Ferenc (a) and Gerhilde (b) Kása, the first small animal surgeons working with AO techniques.

Fig 11a–c a Preoperative x-rays of a fracture of the distal metaphysis of the tibiatarsus in a canary bird; treated by Feri and Geri Kása. b Intraoperative picture showing the incision. c Postoperative x-rays following intramedullary pinning of the fracture with a straight needle.

3â&#x20AC;&#x201A; The Waldenburg Circle

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3 The Waldenburg Circle

Studies of osteosynthesis in large animals The experimental work on horse bones in the Straumann laboratories began immediately after the key meeting between Drs Björn von Salis and Fritz Straumann. The primary questions to be answered were: (1) what type of fractures actually occur in horses; (2) how could such fractures be stabilized with already existing AO implants, and what specific implants and instruments needed to be developed; (3) would such fixations remain stable under the heavy weight-bearing load of an adult horse; and (4) would the fracture eventually heal with the help of internal fixation, and would the attainable stability suffice? For this work von Salis collected horse bones from animals that had to be slaughtered because they had suffered a fracture. X-rays of the bones were taken with the mobile x-ray unit from his Equine Ambulance. Very soon it became clear that on the large bones, such as the adult femur and humerus, osteosynthesis would be almost impossible from a biomechanical point of view. For the other bones of the limbs there seemed to be possibilities for internal fixation, given the fractures were not too complicated. With the largest type of existing AO plates and screws, some of the actual fractures could be well stabilized. Interestingly, the mechanical loading tests that followed demonstrated that it was extremely important to apply the compression plates and screws in a biomechanically optimal way as taught by the AO principles for human surgery. Also the most precise anatomical fracture reduction was necessary to achieve sufficient postoperative stability and immediately allow full weight bearing on the fractured leg. Some of the instruments had to be modified because of the big diameters of the horse bones. The first explorations were encouraging and suggested that there might be certain types of common fracture configurations that could be treated surgically. It appeared that the largest, the 4.5 mm cortex screw and plate system, would be suitable for the major applications and other already available implants seemed useful too. But some new implants and instruments would have to be developed and others adapted to the dimensions of the horse bones (Fig 12). Later on, a 5.5 mm large animal cortex screw was developed by Pohler with improved strength and good holding resistance in cortical and cancellous bone [49]. However, the major question remained: would such

stabilized fractures really heal, and how long would the healing process take? How could the horse be placed on and taken off the surgical table and back on its legs again? This meant that a substantial amount of research had to be conducted. Von Salis worked on this project systematically every Wednesday afternoon and evening at the Straumann Institute. During more demanding surgery on cadaveric bones and horses he was assisted by Guggenbühl and another human surgeon, his friend Dr Peter Dätwyler (Fig 13). The exchange of knowledge The group members complemented each other in an advantageous way. Von Salis was mainly interested in horses and the development of large animal surgery, even though he was a small animal veterinarian too. His friends and colleagues Feri and Geri Kása were specialists in small animal surgery. In addition, Geri Kása was a veterinary anatomist. However, none of the veterinarians had the sophisticated surgical skills needed in the field of osteosynthesis as developed by the AO. It was the experienced surgeon Urs Guggenbühl who contributed these skills. Straumann and Pohler had worked together with the human AO surgeons for several years and were experienced in instrument and implant design, material development, and research. However, what they all had in common was a deep and passionate interest in animals and the desire to heal injured animals and to improve the fate of the increasing number of animal accident victims. One of their main goals was to reduce the number of animals that had to be humanely destroyed because of the lack of viable fracture treatment techniques.

Fig 13 Peter Dätwyler, a human surgeon very instrumental in exploratory large animal surgery during the initial organizational period of AOVET.

Fig 12 A special fragment distractor developed for Björn von Salis by Beat Schenk, the son of Professor Robert Schenk, for equine fracture repair. Each of the two pins for each main fragment had a diameter of 6 mm. The distractor was solidly built and allowed movement of the fragments in any direction. However, it was too heavy and the pinholes too large to be used in clinical work.

4â&#x20AC;&#x201A; Osteosynthesis in small animals

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4 Osteosynthesis in small animals

After the Kásas joined the Waldenburg Group in 1968, Urs Guggenbühl started to systematically instruct veterinarians in surgical techniques (Fig 14). At that time aseptic techniques were taught at university clinics but not universally applied in veterinary surgery because the risks of infection were regarded by many as negligible; an attitude detrimental to bone surgery. The duration of a surgical intervention had to be recognized also as a factor contributing to infection risks. In the same way atraumatic surgical techniques had to be introduced to avoid additional damage to bone, blood vessels, nerves, and soft tissues that in turn could cause complications and delayed healing. Precise anatomical reconstruction of broken bones and joints had to be learned, as well as how to use the specific reduction instruments. All these parameters were prerequisites for successful bone surgery and for achieving the specific goals of the AO: “optimal anatomical and functional reconstruction of bone and joints and early pain free motion.” Guggenbühl instructed veterinarians in how to read x-rays of the fractures, how to generate a strategic plan for the impending surgical procedure, and how to select the appropriate fixation method for each individual case. The AO had developed different kinds of implants and application methods for the various types of fractures occurring at the specific human anatomical locations. Now the veterinarians had to find out which techniques suited best the particular fracture problems they experienced with their different animal patients. One considerable issue was the huge variety in the sizes of their patients (Fig 15). Analysis of preoperative x-rays of clinical cases and the selection of suitable fixation techniques and operative procedures in connection with the critical evaluation of the operative outcome and the healing results became important cornerstones in veterinary education in osteonsynthesis and the spreading of the AO techniques across the globe. The Kásas were active very early and generous in communicating their acquired experiences and knowledge to their colleagues, helping them to learn the methods of AO fracture treatment.

Fig 14 Urs Guggenbühl teaching equine veterinarians during a laboratory session on the management of a third metacarpal bone fracture. Left to right: Urs Jenny, chief assistant at the Surgery Clinic of the University of Zurich, a Belgian veterinarian, Dr Forr, the assistant of Björn von Salis.

Fig 15 Dogs of different sizes: a great dane and a chihuahua.

4 Osteosynthesis in small animals

Guggenbühl often assisted in the osteosynthesis of actual clinical cases of cats and dogs to demonstrate procedures and also gave helpful advice for the postoperative care. All treated clinical cases were closely followed up clinically and radiographically and usually turned out to be successful (Fig 16a–c). The time required for bone healing appeared to be much shorter in small animals than in adult human patients. This was seen as a welcome compensation for the problematic fact that these animals apply full weight on the operated leg immediately after operation. At the same time it explains why the concept of stable internal fixation rapidly became so successful in veterinary surgery. Unfortunately, these animals also love to lick and destroy their bandages, a problem that required some ingenuity from the veterinarians if it was to be overcome. Besides the encouraging experience of successful cases, it became obvious very soon that the smaller bones of dogs and their variable sizes among different breeds required more variety in implant size than were available in the human implant sets at that point in time. The proportionally thin cortices of dog bones with some brittle quality and the relatively wide medullary canals called for certain modifications in surgical techniques. The Straumann Institute with its flexibility in technical improvisations and problem solving was the ideal partner to develop prototypes and to adapt human AO instrumentation and techniques quickly to veterinary requirements. With time, specific implant designs and dimensions were developed for the animal patients. The development of a “broad” dynamic compression plate (DCP) 3.5 in addition to the standard DCP 3.5 serves as example because it was particularly helpful in the treatment of certain common sizes of dogs (see Appendix in Small Animal Maual 2nd ed) [69]. The broad DCP 3.5 has a cross section like the norrow DCP 4.5 and is considerably stronger. Often the smaller versions of implants were also welcomed by the human AO surgeons, such as the special 3.5 mm cortex screw with finer threads and a thicker core, that was developed for dogs and became the conventional Synthes 3.5 mm cortex screw of today [49, 68] (see chapter 8).

c Fig 16a–c One of the first documented cases treated (February 3, 1969) with AO implants. The owner of this Spitz dog returned home from a party and threw the dog out of the window because it had diarrhea and messed up the house. a It broke its femur and its scapula from the fall. The woman drove immediately to the Kása’ small animal clinic where she encountered Geri Kása–Feri was at a meeting and missed this action. In the morning they treated the femur with a four-hole 4.5 mm round-hole plate and the scapula with a five-hole L-plate (not shown here). b 2-week postoperative x-ray of the treated leg). c 23-week follow-up x-rays of the healed fracture with the plate still in place (left), following plate removal (middle) and a few weeks later after the drill holes had healed (right).

4 Osteosynthesis in small animals

Furthermore, the veterinarians realized that it was necessary to develop an optimal and reproducible positioning technique, with standardized x-rays of small animals. The Kásas immediately devoted their attention to this problem and worked out certain standard procedures [50]. They also worked on the problems of postoperative care and generated corresponding techniques. The surgical approaches to the fractured bones had to be studied and An Atlas of the Surgical Approaches to the Bones of the Dog and the Cat by Don Piermattei and Gordon Greeley provided invaluable help [51]. The first osteosynthesis cases were shown at veterinary meetings, and soon some nearby veterinarians joined the small initial study group on Wednesdays, bringing along their problem cases (Fig 17a–c). Guggenbühl never tired of helping and explaining. Often operations took place in the evenings and on weekends in one or the other of the regional veterinary practices. Up until today all group members still remember this period—more than 40 years ago—as a time when they were fascinated by their explorations and the free and successful friendship-based collaboration.

Fig 17a–c Some small animal veterinarians were particularly active in AOVET during the initial phase: (a) Peter Weber, Biel, involved in a conversation with Cathrin von Salis; (b) Pierre and Annie Hauser, Lausanne; (c) Janos Komáromy, Zurich.

5â&#x20AC;&#x201A; Maxlie the horses

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5 Maxlie the horses

In November 1968 after many preliminary investigations on isolated cadaveric horse bones conducted by von Salis, it was time to explore whether an osteotomized bone of a horse would heal without complications after an internal fixation had been carried out. Maxlie, a horse saved from the slaughterhouse by Fritz Straumann was chosen to demonstrate it. Maxlie was anesthetized and maintained in anesthesia with the first BOC “to and fro” portable anesthesia machine used on horses, a novel practice at that time. A transverse osteotomy was performed on the third metacarpal bone with the special atraumatic, oscillating AO bone saw developed by the Straumann Institute. The application of this device, which avoids soft-tissue damage, appeared as useful in large and small animal surgery as when performed on human patients. Although surgical intervention on Maxlie was carried out in a horse barn (Fig 18a), the preparations of the surgeons, the patient, and the surgical field with its surroundings were similar to those applied in human surgery. At that time Stephan Perren was studying the feasibility of titanium plates for use in human fracture management at the AO Research Institute in Davos. Implanting these plates in a horse was therefore a welcome test. The osteotomy was performed by Professor Stephan Perren, Peter Dätwyler, Urs Guggenbühl, Björn von Salis, and Fritz Straumann. Paul Gysin and Jacques Furrer, employees at the Straumann Institute assisted as “operating room” personnel. Maxlie recovered rapidly and after the bone had healed all the implants were removed (Fig 18b−c). Upon investigation, the implants showed neither damage nor wear and tear. Maxlie spent the rest of his life healthy and without any negative effects. This successful osteosynthesis paved the way for internal fixation in the first clinical equine cases in von Salis’ recently opened equine clinic in Frauenfeld (Fig 19a–b). (At that time there were no equine clinics in Switzerland aside from the equine hospitals at the veterinary schools at the Universities of Zurich and Bern). The surgical interventions had to always be conducted in the evenings or over holidays because during the day the two assisting human surgeons, Guggenbühl and Dätwyler, had to take care of their human patients. One night when lightning struck an electrical distribution center in the area causing loss of electricity in the whole region, the final sutures of a surgical intervention on a horse had to be performed with the help of automobile headlights.

Fig 18a–c The first osteotomy on a live horse, Maxlie, carried out in a barn. a Intraoperative x-rays of the osteotomy. b Immediate postoperative photograph of Maxlie, following recovery from anesthesia. c 35-week postoperative x-ray showing the healed osteotomy with the plates still in place.

Fig 19a–b One of the first clinical equine cases treated by Björn von Salis with internal fixation according to AO principles. a Dorsopalmar (left) and lateromedial (right) x-rays of a nondisplaced, biarticular, sagittal fracture of the proximal phalanx. b 14-week postoperative, dorsopalmar radiograph of the healed fracture, which was treated with three interfragmentary cortex screws inserted in lag fashion (compression).

6â&#x20AC;&#x201A; Institutionalizing the Waldenburg Circle: the foundation of AOVET and pioneering work

Inst itut ional the izing foun dati t on o he Walde f AO VET a nburg Circle nd P IONE ERIN : G wor k

6 Institutionalizing the Waldenburg Circle: the foundation of AOVET and pioneering work

The founding of AOVET Shortly after the successful osteosynthesis on Maxlie and on a series of small animals, members of the Waldenburg Circle participated in the human AO courses in Davos in December 1968. During those courses, a proposal began to take shape for the formation of an AO group for veterinarians with the aim to study and introduce osteosynthesis corresponding to AO principles into veterinary medicine. After reviewing the work done thus far by the Waldenburg Circle and recognizing the generally poor state of bone surgery in veterinary medicine, the AO board agreed to form an AO veterinary group, and transfer AO techniques and knowledge to the veterinary discipline. On August 31, 1969, AOVET was founded at an official ceremony carried out by Hans Willenegger in the city hall of Waldenburg (Fig 20). In addition to the founding members (Fig 21) a number of Swiss, German, French, Dutch, and US veterinarians were present, together with some friends from the AO and the Straumann Institute. Björn von Salis became the first president of AOVET. Ortrun Pohler was asked to act as secretary. The constitution of the AO was adopted by AOVET with certain modifications, in particular regarding the criteria for membership. The AOVET group intensified and systemized their work enthusiastically. The clinical cases treated by the AOVET members were documented in Waldenburg on cards with pertinent data and copies of the x-rays. The surgeons obtained copies of those cards from their cases. Similiar to the AO, spring and autumn meetings were organized each year with clinical and administrative membership sessions. Maurice Müller asked Urs Guggenbühl officially to take over the responsibility that the veterinarians carry out their osteosyntheses properly in accordance with the AO principles. Fritz Straumann continued to provide support and access to the laboratories of his institute. Pohler worked systematically with other employees for the internal and external organization of AOVET, the development of implants and instruments for large and small animals, the performance of testing and research, and preparation of teaching aids. Through her, AOVET was also–first indirectly, later directly–represented in the Technical Commission (TK) of the AO.

Fig 20a–b Festivities following the opening ceremony of AOVET on August 31, 1969, at the restaurant Bechburg near Waldenburg.

Fig 21a–h The Founding Members of AOVET; top row left to right: Björn von Salis, Fritz Straumann †, Ortrun Pohler, Hans Willenegger †; bottom row: Urs Guggenbühl†, Peter Dätwyler†, Geri Kása, Feri Kása.

6 Institutionalizing the Waldenburg Circle: the foundation of AOVET and pioneering work

Pioneering work of AOVET Later in 1969 small instruction workshops started, offering lectures and practical exercises with implants and instruments (Fig 22). In the years that followed, veterinary workshops were also offered abroad and during the AO course weeks held every year in December in Davos. Guggenbühl expanded on his instructions and developed a whole lecture series on various surgical and clinical topics (in time these lectures were also given in French and English). Von Salis and the Kásas started to present lectures on AO techniques at professional veterinary meetings and AOVET courses. In October 1969 at the veterinary school of the University of Zürich during a German Veterinary Medical Society (DVG) convention two lectures were given: one by Guggenbühl and von Salis on AO osteosynthesis, and one by the Kásas and Paul Hutzschenreuter, on osteosynthesis in small animal medicine. Following these lectures there were heated discussions about compression osteosynthesis because at that time their colleagues believed, as did human surgeons 10 years before, that compression causes bone resorption. However, the results of the AO research, and the successful and well-documented clinical small animal cases of the AOVET members, refuted these doubts within a short period of time. In December 1969, some AOVET members attended the human AO course in Davos and met a group of veterinarians, Wade Brinker, Hugh Butler, Bruce Hohn, Jacques Jenny, and Don Piermattei, who came from the US and were very interested in osteosynthesis. An exchange of experiences and ideas took place, and the ground was paved for an extensive cooperation. More details on the AOVET development in the US are given in chapter 7. In January 1970, a Swiss AOVET course took place in Bettlach (Fig 23). In the same month the Kásas gave a lecture during the annual meeting of the DVG in Duisburg in which they showed a series of AO osteosyntheses on small animals. This caught the attention of the German veterinarians and they started participating in AOVET events. Inspired through the attendance of the recent human AO course in December, Professor Bruce Hohn (Fig 24) organized the first course on the internal fixation of fractures and nonunion at Ohio State University (OSU) in Columbus, Ohio in March 1970. In the same year the AO TK accepted the first veterinary small animal equipment set with round-hole plates of particularly small dimensions for the small screws. Later on those plates were also integrated in the human standard sets.

Fig 22 Feri and Geri Kása teaching small animal veterinarians the technique of axial compression of a fracture on cadaver legs, with the help of the tension device.

Fig 23 Participants of the first AOVET course organized in January 1970 in Bettlach, home of Mathys AG. Some of the participants are identified by numbers, left to right. (a) 1: Jan Gajenthan, 2: Arnold Müller, 3: Herbert Post, 4: Prof Paul Hutzschenreuter, 5: Urs Jenny, 6: Reto Scartazzini, 7: Robert Schenk, 8: Karl Gabrisch, 9: Peter Dätwyler, 10: Peter Bartels, 11: Geri Kása, 12: Margrit Jaques, 13: Feri Kása, 14: Pierre Gonin, 15:Pierre Hauser, 16: Gianpietro Togni, 17: Urs Guggenbühl, 18:Axel Bubloz, 19:Gottfried Ueltschi, 20: “Arco” von Salis, 21: Margrit Diehl, 22: György Halmos, 23: Freek Meutstege, 24: Christoph Uehlinger, 25: Janos Komáromy, 26: Mario Ferrari, 27: Thomas David, 28: Laszlo Lakatos; 29: Hans-Georg Niemand, 30: unidentified; 31: Rudolf Zeller, Hannover; 32: Hans-Georg Stihl; 33: Ortrun Pohler, 34: Carsten Rosenhagen, 35: Oswald Padrutt; 36: Liesbeth Mathys, 37: Fridolin Séquin, 38: Robert Mathys; (b) 39: Jacques Furrer, Straumann Institute; 30: Björn von Salis.

6 Institutionalizing the Waldenburg Circle: the foundation of AOVET and pioneering work

In January 1971 AOVET held its first veterinary course in English, in Davos along with the human courses. Parts of the scientific human lectures were included in the veterinary program. Professors Hohn and Jenny, a Swiss veterinarian teaching at the University of Pennsylvania, (Fig 25) were faculty members. Professor Sakki Paatsama, a well-known small animal surgeon (Fig 26) from Finland, was a guest lecturer. From then on AOVET courses were offered annually in Davos in parallel with the human courses in December. In March 1971 Hohn again organized a course at OSU which led to the creation of the present-day courses in Columbus, traditionally held each year.

Fig 24 Professor Bruce Hohn of Ohio State University during the first Small Animal Course in Davos, December 1970. Practical exercises on cadaveric dog bones in the basement of the Congress Center.

Fig 25 Professor Jacques Jenny, University of Pennsylvania (left), and Howard Rosen, Clinical Professor of Orthopedic Surgery at the NYU School of Medicine/Mount Sinai School of Medicine in New York City, a treasured friend of the veterinarians (right).

Fig 26 Professor Sakki Paatsama of the University of Helsinki during an early AO function.

Fig 27 Professor Ulrike Matis, Director of the Veterinary Surgery Clinic at the University of Munich, the first female chairperson of AOVET.

In spring 1972 an instruction course again took place at the Mathys company in Bettlach. At the Medical-Technology Congress 1972 in Stuttgart two AOVET lectures were presented: one by Feri Kása on “Frakturbehandlung und Korrekturosteotomy beim Kleintier” (Fracture management and corrective osteotomy in small animals), and one by von Salis on “Frakturbehandlung und Arthrodese beim Grosstier” (Fracture management and arthrodeses in large animals). In the same year von Salis gave a lecture on his findings and experiences on operative AO techniques in horses at the annual Convention of the American Association of Equine Practitioners in San Francisco [52]. In 1973 an AOVET publication on stable internal fixations on dogs [53] was published and in 1974 at the DVG Annual Meeting in Mannheim the Kásas lectured on the treatment of humeral fractures. In the same year, Professors Ulrike Matis (Fig 27) and Roberto Köstlin (Fig 28) of the University of Munich published a paper on compression osteosynthesis on the femur of cats and dogs [54]. The expansion of the different osteosynthesis treatments during the second half of the 1970s is reflected in two publications by Ulrike Matis, who performed small animal osteosyntheses in a wide range of applications [55, 56]; and in two papers by Geri and Feri Kása, [57, 58] the latter was given at a human AO course. Further papers on the applications of osteosynthesis in small animals were published in the 1980s [59–62]. In 1986 the Kásas published a series of toy breed cases, which because of their very delicate small bones represent a special challenge in small animal fracture management [63].

Fig 28 Professor Roberto Köstlin of the University of Munich was of particular help as a faculty member with Spanish language skills at AOVET courses during the early days.

6 Institutionalizing the Waldenburg Circle: the foundation of AOVET and pioneering work

Many members of the AO were very generous and supportive in contributing lectures on special topics at the various veterinary courses. Robert Schenk (Fig 29), scientific AO member and director of an excellent histological laboratory at the University of Basel, later vice-director of the Anatomical Institute of the University in Bern, became a very valued and good friend of the verterinarians. He was always ready to lecture on subjects of bone structure—metabolism, and bone healing. In time, interesting research projects were developed with him. For decades he lectured at the veterinary courses in Columbus, and Davos. Stephan Perren (Fig 30) always had an open ear for the problems of the AOVET members and was a supportive friend, accommodating their courses in Davos as well as scientific projects. He appreciated the veterinarians’ common sense and quick realization Fig 29 Professor Robert Schenk, a true of AO concepts and new research results. Until his death, friend of the veterinarians, with one of Hans Willenegger was a staunch supporter of AOVET in his favorite stress releases, his “Schwiizer Örgeli”—a special Swiss accordion. various aspects. He was a tireless lecturer on AO principles and developed several slide presentations for these one-on-one teaching sessions (Fig 31). After these sessions he presented the slides to the recipients of these lectures. Increasingly, the veterinarians learned to treat all the relevant bone injuries and skeletal corrections [64, 68–70] in small animals in much the same way as in human patients, although they frequently had to improvise. They also acquired the skills to apply their operation techniques to injured exotic animals like birds or polar bears (Fig 32a–e) [65]. In large animals, osteosynthesis was also performed with astonishing results; however, possibilities remained restricted because of the large size of the animals, as well as their anatomical and biomechanical conditions. During AOVETs pioneering days, one practical aspect that had to be kept in mind was the financial costs. When the veterinary activities on AO osteosynthesis started, private practices, even university clinics were not equipped for the performance of osteosynthesis corresponding to AO human clinical standards. Decisions to include such AO open fracture treatment techniques into the clinical routine of veterinary practices or clinics required considerable investment in technology (eg, high- quality x-ray and sterilization equipment), implants and instruments, and probable additions of rooms and assisting personnel. Thus osteosynthesis appeared to veterinarians like an expensive hobby. Also, performing the

Fig 30 Professor Stephan Perren, since 1967, Director of the AO Research Institute Davos. He supported the veterinarians strongly.

Fig 31 Professor Hans Willenegger and his long-term secretary Elisabeth Spicher during one of their frequent slide sorting sessions at his home in Schauenburg near Liestal, 4 weeks before his death in 1998.

Fig 32a–e A female polar bear at the Karlsruhe Zoo broke its maxilla. The Kása’s repaired it with two 3.5 mm DCPs and a reconstruction plate 2.7. The plates were removed after the fractures had healed. a Preoperative picture of the polar bear’s head. b Intraoperative picture during the repair (the commercially available drill shown here was gas sterilized, a novelty at that time. c 16-week intraoral postoperative x-ray of the repaired maxilla showing the implants used. d The still anesthetized patient was transported with the help of a fork lift back into its cage. e The the patient shortly after recovering from anesthesia, still slightly uncoordinated in its cage.

6 Institutionalizing the Waldenburg Circle: the foundation of AOVET and pioneering work

surgical interventions was still very time-consuming because an economic routine was yet lacking. Furthermore, there were no reimbursements from health insurance plans—neither for small nor large animals—unlike the insurance policies for human patients, and so the animal owners could not be asked to pay for the actual costs. Consequently, veterinarians had to try to carry on their practices with other clinical treatments. Only slowly, with the increase in successful osteosyntheses and the growing attitude of animal owners to consider their pets as members of the family with the responsibility to provide them with the best possible medical treatment were veterinarians able to obtain adequate reimbursement for their work. There exists some trade-off in so far as the stable internal fixation techniques allow very early postoperative discharge of the animal patients from the clinics, which reduced some treatment costs. International activities of AOVET AOVET enjoyed an immediate international response. In the early 1970s, in addition to the courses in the US and Davos, courses were offered in Sweden—encouraged by Harry Pettersson—Finland, and England, as well as in France—encouraged by Pierre Hauser. These courses offered the same content because the course faculties (lecturers and instructors) remained almost the same in Europe and in North America. The course faculties soon realized the importance of their united approach. They organized meetings throughout the year where the courses were prepared, critical discussions took place, and new concepts for courses were planned. Annual AOVET membership meetings were held in connection with the Davos courses and provided further opportunities for organizational activities and planning. In the US the annual meetings of the Veterinary Orthopedic Society (VOS) were also events where AOVET members met and organized their own additional workshops. The basis for this type of cooperation was the supporting structure of the AO organization as well as the friendship and loyalty among the veterinarians themselves, who had a common goal in developing systematic operative fracture treatment in veterinary medicine. Elaboration of the multitude of surgical treatments for different fracture types and orthopedic corrective interventions in different anatomical areas as they are shown in the small and large animal manuals [66–70] are the result of this fruitful cooperation.

In the US the veterinarians had no intention to form a national AOVET group. Therefore they became individual members of the existing AOVET organization. The same type of individual AOVET membership was arranged for members from other countries. In 1972 AO International (AOI) was established with Hans Willenegger acting as president. Already nominated in 1977, AOVET was confirmed as an official AOI member in 1979. Certain national groups or smaller circles were also active. For example, Professor Freek Meutstege (Fig 33) led a working circle in the Netherlands. In the early 1970s the French AOVET members began offering an annual veterinary course in France in (Fig 34). In 2004 the courses were moved to different locations in the French Alps, such as Les Deux Alpes. The organization of parallel courses in diagnostic imaging filled quickly and attracted many participants, exhibitors and sponsors. Professor Klaus Bonath (Fig 35) offered successful AOVET courses at the University in Giessen, Germany, beginning in 1982. From the start the Swiss and German AOVET members undertook joint programs. In 1986 a German AOVET group was established with Feri Kása as president who had very good connections to the AOVET group and the AO in Germany. The Austrian AOVET members together with the Swiss members cooperate closely with the German AOVET group and organize joint annual meetings. Annual 1-day student workshops have been organized at the University of Vienna by Dr Norbert Kopf (Universitätsdozent) (Fig 36) since 1997. In cooperation Dr Günther Schwarz offers every second year an AOVET course for veterinary practitioners in Salzburg, Austria. In Berlin, Professor Leo Brunnberg (Fig 37) has offered student workschops since 1998. From 1972 on, Feri Kása was active at the Veterinary Medical University of Budapest, Hungary, establishing operative fracture treatment corresponding to AO principles. In 1991 he was awarded an honorary professorship in recognition of his teaching.

Fig 33 Professor Freek Meutstege, University of Utrecht, third AOVET President and a dedicated faculty member of AOVET courses from the beginning.

6 Institutionalizing the Waldenburg Circle: the foundation of AOVET and pioneering work

Fig 34 Four prominent members of the organizing committee of the French AOVET Courses, left to right: Michel Baron, a past president of AOVET; Jacques Drapé, La Rochelle; Didier Fontaine, Nantes; Jean-Pierre Cabassu, Marseille, France. Not shown Yves Latte, Grenoble, France.

Fig 35 Professor Klaus Bonath of Giessen, the organizer of the first German AOVET Courses and student workshops at his university.

Fig 36 Professor Norbert Kopf of the University Vienna, one of the first Austrian small animal veterinarians involved in AOVET.

Fig 37 Professor Leo Brunnberg of the University of Berlin, an early collaborator of AOVET.

Bruce Hohn of the Veterinary School of OSU established a nucleus of AOVET activities in the US. Human surgeons from the local hospitals liked to participate in veterinary courses. The AO research appeared to inspire a wave of clinical studies at different veterinary schools and human medical institutions in the US. In turn, surgeons and scientists from Europe enjoyed meeting and collaborating with their colleagues in the US. Schenk introduced histological research techniques to the laboratories at OSU. Straumann sponsored a surgery unit at the Veterinary Clinics of OSU to enable clinical research independent of routine clinical work. In the following chapter a short review is given of the development of AOVET on the other side of the Atlantic Ocean, in the US. Again, the search for improved operative fracture treatment in animals, a series of special circumstancesâ&#x20AC;&#x201D;a hidden network of correlationsâ&#x20AC;&#x201D;and human openness led to the introduction of systematic AO osteosynthesis in the US.

7 The hop over “the big pond”

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7 The hop over “the big pond”

Dr Bruce Hohn was engaged in a private mixed practice for much of his early career in Minnesota. In a life-changing event, he was able to secure a 1-year fellowship in orthopedic surgery at the Mayo Clinic in Rochester, Minnesota. In the mid-1960s he left private practice to become head of Small Animal Surgery at the Animal Medical Center (AMC) in New York. Hohn’s connection with the AO started the day a Saint Bernard was presented to him with a comminuted fracture of the femur. He had heard about a certain Dr Howard Rosen in New York, who was using metal plates and screws to stabilize fractures in people with great success. Howard Rosen heard about the techniques the “crazy Swiss surgeons” (as the AO founders were called in the US) were promoting to manage fractures. Intrigued by these techniques, he wanted to purchase the equipment. However, at that time the instruments and implants were only sold to doctors that participated in a special course in Switzerland, where their proper use was instructed by the founders. Howard Rosen didn’t wait long, signed up for the next course and returned to the US with all the instruments and as many implants as available at that time—everything packed into his suitcase. Rosen at that time was the only MD surgeon in North America who applied AO principles and soon became one of the course instructors in Davos. At that time, there were no such courses taught to MDs in North America. Bruce Hohn contacted Rosen and asked him if he could borrow this marvelous equipment to repair the dog’s fracture. Howard Rosen asked if he knew anything about using plates. Of course Hohn had never seen a plate before but he was sure he could figure it out. So Rosen suggested to Hohn that he would bring his equipment to the AMC and they could work on the fracture together. That was, as they say, the start of a lifelong friendship. Throughout the rest of his life, Howard Rosen, a soft spoken gentleman and one of the most prolific, charismatic and distinguished teachers of AO techniques maintained a special interest in AOVET members and their patients. He was invited to numerous AOVET courses and meetings of the Veterinary Orthopedic Society (VOS) to speak on his favorite topic “Complications”. He cherished his contacts with the veterinary group and inspired many young residents to pursue a career in veterinary orthopedic surgery.

In December 1969 Bruce Hohn and four other veterinarians from North America went to Davos to a human AO course. Professor Wade Brinker (Fig 38), who would later become the second President of AOVET and the first North American President, was a member of that group. Another distinguished member of the group was Professor Jacques Jenny, actually a Swiss expatriate, who was teaching equine surgery at the University of Pennsylvania at the New Bolton Center. Previously in 1943, as a resident at the University of Zürich, Jacques Jenny assisted Dr Knoll and Dr Willenegger in the first clinical intramedullary nailing in a dog (see Fig 3). Unfortunately, Jacques Jenny died after the Davos course in 1972, much too early. However, before his death, Professor Jenny had established the use of AO techniques at his school. The last horse Jenny performed surgery on before he died was “Hoist the Flag”, who broke its proximal phalanx (comminuted fracture) and the adjacent third metatarsal bone (condylar fracture) of the right hind leg. The surgery took 6 hours with Dr Delahanty of Cornell University assisting. At the end of the surgery the first ever fiberglass cast was applied to the injured limb. John Alexander and David Nunamaker did the cast changes and the horse survived. Unfortunately “Hoist the Flag” bit off its grooms thumb in their presence—it was not a nice, well-mannered horse. During the Davos courses in 1969 Bruce Hohn met Fritz Straumann and Ortrun Pohler. At that time, Hohn had left the AMC and was a professor at OSU in Columbus, Ohio. He left Davos knowing that he wanted to organize and chair an AO course at OSU, so in March 1970, 99 veterinarians and faculty were present at the first annual course on “Internal Fixation of Fractures and Non-unions.” This course was cosponsored by OSU and AO. The following year the veterinary course was combined with a human AO course—the first human AO course to be offered in the US. An equine course was also added to the event with the help of Professor Jenny. As previously mentioned he passed away a year later and could therefore not reap the full harvest of his work. Fig 38 Professor Wade Brinker of Michigan State University served as the second AOVET President. He promoted the systematic internal fixation technique in small animals. He was an avid downhill skier.

7 The hop over “the big pond”

Fig 39 Faculty of the Columbus Courses 1977; left to right, back row (standing): M Olmstead, unidentified, D McLean, P Call, W Betts, G Cormack, T Dueland, D Piermattei, unidentified, M Herron, L Wallace, W Reed; fourth row (standing): T Lenahan, S Turner, A van de Water (Johnson), G Sumner-Smith, P Call, F Rheinlander, H Buttler, G Fackelman, T Braden, B Hull, W Daily, C Newton, C Knecht; third row (sitting): unidentified, unidentified, W Brinker, unidentified, W Riddle, H Rosen, B Hohn, D Rudy, J Stoyak, R Gurevitch, S Crain, D Crow, unidentified; second row (stitting): T Turner, B Buttler, S Stoll, E Trotter, R Shank, B Slocum, B Horne, M DeAngelis, JT Alexander, W Hoeffle, E Craig, unidentified; front row (standing): D Prieur, A Guggenbühl, T Rüedi, H Willenegger, O Pohler, R Schenk, B von Salis, and B Rahn.

From then on the courses in Columbus were offered annually (Fig 39) with Bruce Hohn as General Program Chairperson (see Fig 24); in 1997 Professor Marvin Olmstead (Fig 40) became co-chairperson. The equine courses were chaired by Professor Al Gabel with Dr Larry Bramlage as co-chairperson. These were different times, when lectures were given with old-fashioned slide projectors. Text slides were white letters on a solid blue background and not multicolored with interesting backgrounds as they are today. In the early 1970s Bruce Hohn and Marvin Olmstead were responsible for developing teaching videos for practical exercises in the small animal courses following the AO guidelines. In 1977 Professor Gustave (Bud) Fackelman (Fig 41) took his young resident Dr Joerg Auer (Fig 42) to Columbus before the courses to prepare the first teaching videos for the equine course.

Fig 40 Professor Marvin Olmstead, of the Ohio State University, co-chairperson of the Ohio Courses. After Bruce Hohn passed away, Olmstead succeeded him as General Program Chairperson.

Fig 41 Professor Gustave (Bud) Fackelman of the University of Pennsylvania was a strong and avid promoter of the application of AO Techniques in large animals. To his right Andi Kása, the son of Feri and Geri, who eventually took over responsibilities at the small animal clinic in Lörrach, Germany.

Fig 42 Jörg Auer, at that time of Texas A&M University in College Station, TX, together with Len Langlands, a small animal veterinarian from Johannesburg, South Africa, who organized the first small animal AOVET courses in his home country and attended the Davos Courses every year just to be with the AOVET group.

7 The hop over “the big pond”

The Veterinary College at OSU established itself as the center for AOVET activities in North America, with Bruce Hohn as the leader. On the small animal side, Hohn was supported by Professors Wade Brinker and Terry Braden of Michigan State University, Professor Geoff Sumner-Smith, Professor Don Piermattei of Colorado State University (Figs 43 and 44), Professor Larry Wallace of the University of Minnesota (see Fig 33), Professor Robert Leighton of the University of California Davis, Professor Tass Dueland of the University of Minnesota, and Professor David Nunamaker of the University of Pennsylvania (Fig 45). The equine side of AOVET in North America was mainly promoted by Al Gabel of OSU, and Gustave Fackelman of University of Pennsylvania. In time younger faculty emerged among whom Marvin Olmstead, Larry Bramlage (Fig 46), and Jörg Auer followed in the footsteps of their teachers. In 1979 the human AO course was moved to Sun Valley, Idaho, a location near a ski resort. This allowed the veterinary course to increase the number of participants and expand from basic small animal and equine courses to advanced courses in each discipline. These courses grew over the years to annually host between 350 and 400 veterinarians and an international faculty of over 50 veterinarians, medical doctors, and scientists. Following Bruce Hohn’s untimely death in 1986, Marvin Olmstead became General Program Chairperson and shortly after Larry Bramlage was named co-chairperson for the equine courses. Olmstead remained in that position until just before retirement from OSU in 2002. From these courses, veterinary fracture management according to AO techniques spread throughout the US to all university veterinary schools and colleges. The courses are now a standard element in the education of veterinary students, interns, and residents. Every spring from 1970 until 1988 AOVET courses were taught at OSU in Columbus in their continuing education facility, the Fawcett Center for Tomorrow (Fig 47). From 1989 onward the courses were moved first to the Hyatt Regency Hotel in downtown Columbus and in 2005 to the Hilton Easton Mall, still in Columbus. For years the Continuing Education Credits were provided by OSU. Since 2002, Kenneth Johnson (Fig 48) of Sydney, Australia (former professor at OSU), acts as small animal chairperson and Larry Bramlage, together with Alan Ruggles (Fig 49) of Rood & Riddle Equine Hospital, Lexington,

Fig 43 Professor Geoff Sumner-Smith, a past AOVET President, in deep discussion on AO teaching videos with Geri Kása during a Davos Course dinner.

Fig 44 Professor Don Piermattei, a past president.

Fig 45 Professors David Nunamaker of the University of Pennsylvania (the second equine specialist past AOVET President), Larry Wallace of the University of Minnesota, Minneapolis, and Freek Meutstege of the University of Utrecht (third past AOVET President). In the background Len Langlands during an AOVET function in Davos.

Fig 46 Dr Larry Bramlage, co-chairperson of the Columbus Equine Courses, here addressing the AAEP audience after he became President-Elect in 2003— one of the key large animal surgeons who was instrumental in the progression of equine fracture repair.

7 The hop over “the big pond”

Fig 47 Faculty of the Columbus courses 1985, left to right, back row: T Turner, R Kaderli, W Hoeffle, L Wallace, J Auer, G Fackelman, D Prieur, D Nunamaker, R Vannini, R Boudrieau, R Fingland, D DeYoung, W Betts; third row: J Dee, D Rudy, S Roe, R Ringwald, B Hohn, M Olmstead, A van de Water (Johnson), T Fossum, M Shamis, L Shamis; second row: R Copeland, S Payne, W Read; front row: T Lenahan, T Braden, CW McIlrwaith, O Turner, F Meutstege, S Stevenson, L Bramlage, R Schenk, A Gabel, O Pohler, W Brinker, D Piermattei, R Schneider, P Montavon, and R Emberson.

Fig 48 Professor Kenneth Johnson, presently of the University of Sydney, took over as chairperson of the Columbus Small Animal Courses from Marvin Olmstead.

Fig 49 Dr Alan Ruggles, co-chairperson of the Columbus Equine Courses.

Kentucky (former OSU faculty members), serve as co-chairpersons of the equine courses. These are now run by the Education Division of AO North America, which also provides the CME credits. Recently, additional Small Animal Basic, Advanced, and Master courses were organized in San Diego, California, during the summer months. Also, in alternate years, an Equine Master Course was added, resulting in a total of six to seven AOVET courses being organized annually in the US. Workshops dealing with specific AOVET applications are frequently organized at national and regional meetings throughout the US. It was Bruce Hohn’s idea to establish an AOVET Residency Program at OSU. Willenegger supported this idea and was helpful in establishing a special fund at OSU for the purpose of financially supporting this residency. Money was donated from different sources. The three surviving AO founders, Professors Müller, Allgöwer, and Willenegger, donated part of the prize money received with the prestigious 1987 Swiss “Benoist Prize,” to the Hans Willenegger Residency Fund. AOVET also supported the fund with a free membership account. The endowment supported a 2 to 3-year residency at OSU for a European veterinarian, interested in orthopedic surgery, enabling the resident to acquire expertise not readily available in Europe. It was planned that these residents would then return to Europe to teach what they had learned in the US. As increasing inflation reduced the value of the fund, it was clear that the initial capital provided was not enough to sustain a 3-year residency. Additional funds were provided by OSU for some time. Every 3 years the AOVET board received applications from a number of European candidates, who were preselected by the faculty at OSU. All residents had specialized in small animal surgery, with the exception of two special equine (1-year fellowship) recipients. The residency is still offered; however, as most of the money comes from OSU, its faculty now makes the final selection decision.

8 Spreading the word—AOVET Center Waldenburg

AOVE Spreadin T Ce nter g the w Walde ordâ&#x20AC;&#x201D; nbu rg

8 Spreading the word—AOVET Center Waldenburg

To support the expansion of AOVET, an AOVET Center was established in Waldenburg in 1976 and Dr Dieter Prieur (Fig 50) was asked to lead it. Ortrun Pohler (appointed as scientific member of the human AO in 1973) transferred responsibilities for the organization of the AOVET secretariat to Prieur since she had started to work at the Metallurgical Institute and with the Veterinary School at OSU and with other US-based technical organizations, commuting between Switzerland and the US. The Straumann Institute provided office space for the AOVET Center with assistants, infrastructure, working materials, and other help, while other parts of the budget were supplemented by the AO. Dieter Prieur became the first executive secretary of the AOVET organization. He prepared the official and educational meetings, coordinated, and organized the increasing numbers of local and international AOVET courses. He taught and lectured at international veterinary conferences, and published on the subject of internal fixation [27, 61, 68, 71, 72]. He furthered the development of AOVET instrumentation and operation techniques. With the Mathys company he developed the doublehook plate with the corresponding instruments for the correction-osteotomy procedure on the proximal femur of dogs. He supported his veterinary colleagues in various ways and generated fruitful collaborations internationally. Hence, he helped to create an active core of membership within AOVET.

Fig 50 Dr Dieter Prieur (left) served as Executive Secretary of the AOVET Center in Waldenburg from 1976 to 1991. Dr Gary Clayton-Jones (right), a past president of AOVET and a valued long-term faculty member from UK.

The formation of the AOVET Center led to an increased structuring of the AOVET organization and the spreading of veterinary operative fracture treatment. The function of the executive secretary provided continuity and stability. AOVET introduced an office term of 2 years for the elected president. However, before the new president takes office he/she surves 2 years as “president-elect” and after his/her 2 years in office he/she would remain 2 years as “past-president.” This latter presidential turnover protocol contributed to the organizational continuity as well. In 1980 Professor Wade Brinker was elected as the successor of Björn von Salis who held the presidency for over 10 years. All the AOVET presidents (see Epilogue) have been dedicated, active AOVET members, linked through friendship to many of their colleagues in the organization. Similar to the AO, commissions for research and education were also introduced. During the reorganization of the AO Technical Commission (TK) in 1982, the veterinarians received their own individual AOVET-TK subcommission chaired by Pohler, who had continued to support AOVET interests. In addition to the previously mentioned 3.5 mm cortex screw, other examples of cooperation and exchange between the AO and AOVET were small plates to be used with 2.7 mm screws that had been developed for small animal surgery. These implants were subsequently successfully applied in craniomaxillofacial (CMF) surgery. The mechanical properties and measured performance characteristics of the 3.5 mm screws developed for veterinarians were documented by Pohler [49, 68]. By 1982 some of the veterinary clinics had many well documented cases without any complications or failures of those screws. Therefore, when the advantage of this type of screw was discovered by the human surgeons, the data generated by the small animal veterinarians provided adequate proof of their superior functionality. Consequently, after a short pilot testing phase, AO TK was able to release this screw directly for application in human surgery. It became the conventional 3.5 mm cortex screw successfully applied today. Such implant design transfers were possible because the typical veterinary implants were produced from the same standardized high-quality implant material and underwent the same demanding technical manufacturing processes as the implants for human surgery. The same is true for the instruments.

8 Spreading the word—AOVET Center Waldenburg

To support the AOVET courses on the small animal fracture management and give veterinary surgeons some basic introduction to internal fixation techniques, a booklet for internal use was created by Geoff Sumner-Smith, Dieter Prieur, Terry Braden, and Wade Brinker on “AO Techniques in Small Animal Orthopedic Surgery.” For years this booklet was kept continuously updated. Comprehensive presentations of the systematic AO osteosynthesis techniques that had been developed for orthopedic corrections and for the operative treatment of the various fracture types at the different anatomical locations in large and small animals were provided in specific manuals. In 1982 the Manual of Internal Fixation in the Horse was published by Fackelman and Nunamaker in collaboration with Björn von Salis (Fig 51) [66]. A second revised edition followed in 2000 [67] edited by Gustave E Fackelman, Jörg Auer, and David Nunamaker in cooperation with Larry Bramlage, Dean Richardson, and Björn von Salis (Fig 52). In 1984 the Manual of Internal Fixation in Small Animals was published by its editors Wade Brinker, Bruce Hohn, and Dieter Prieur (Fig 53) [68]. Twenty additional contributors were included in the production of this manual, clearly demonstrating the effective collaboration among the veterinary surgeons. In addition, this work had a positive effect on the clarification and unification of the methodical AOVET principles, and triggered further working projects. In 1997, there followed a revised second edition of the Manual of Internal Fixation in Small Animals [69] where Marvin Olmstead had reliably substituted the late Bruce Hohn as a co-editor. And in 2005 the first version of AO Principles of Fracture Management in the Dog and Cat was published by Ann L Johnson, John EF Houlton, and Rico Vannini [70]. The editing, layout, and typesetting were completed by AO Publishing and published by Thieme Verlag (Fig 54).

Fig 51 The 1st edition of the AO Manual of Internal Fixation in the Horse.

Fig 53 The 1st and 2nd enlarged editions of the AO Manual Manual of Internal Fixation in Small Animals.

Fig 52 The 2nd edition of the AO Principles of Equine Osteosynthesis. This represents the first AO Manual of the new era containing video clips of basic principles on a CD-ROM. The manual was published by the newly formed AO Publishing under Rainer Egle.

Fig 54 The 3rd edition of AO Principles of Fracture Management in the Dog and Cat.

8 Spreading the word—AOVET Center Waldenburg

The AOVET has always closely followed new AO concepts and developments, adapting and integrating them into their programs. The limited contact dynamic compression plate (LC-DCP), point contact fixator (PC-Fix), and in particular the locking compression plate (LCP) became in many variations part of the AOVET equipment. As a matter of fact AOVET members were actively involved in some steps in the development of the forerunners of the LCP and PC-Fix. The first Fig 55 One end of the vetericlinical trial following research studies on sheep with the nary locking compression plate PC-Fix were conducted on large animals at the University (LCP) is pointed and tapered like of Zurich. Experiences gathered with these implants led to a regular LCP, whereas the other the development of the PC-Fix II, which was initially tested end is rounded and contains a stacked combi-hole that allows as 3.5 mm implants on small animals at the University of placement of a locking head Zurich again. Eventually the implants were released for use screw much closer to the joint. on human humeral fractures. The specific veterinary tibial This prevents protruding of the plateau leveling osteotomy (TPLO) plate makes successful tapered end when a locking head has to be placed near the joint. use of the locking screw principle where a fine thread at the The stacked combi hole also allower portion of the screw head interlocks with a thread in lows insertion of a cortex screw. the plate hole. In plate shafts bridging severely comminuted fracture zones, locking screws can stabilize the length precisely. The veterinarians changed the design of their LCPs to incorporate a stacked locking hole on one side of the plate associated with a round edge instead of the tapered and pointed end as seen in the human plates. This allows insertion of locking head screws closer to the articular margin without having the tapered end protruding over the joint margin (Fig 55). The increasing emphasis placed by the AO on atraumatic operation techniques and “biological” osteosynthesis concepts, as expressed by Perren [43, 73], were of particular interest to AOVET members. Observations by Matis [74] of certain complications in smaller dogs with comminuted fractures, where the small size of fragments cannot be well stabilized with screws without damaging vitality, could be explained. Clinical investigations by key AOVET members on osteosyntheses carried out according to biological concepts demonstrated that it is advantageous to keep the vitality of comminuted fracture segments intact [75, 76].

The bridging fixation of such bone defects requires certain plate properties. The plate strength and rigidity must be such that neither lasting-bending deformation nor too much elastic bending occurs. The latter could induce implant failure under alternating-bending stresses. Excessive cross sections of plates could cause irritation of the soft tissues and render closure of the soft tissues over them difficult. To assess what type of plate would be best for a bridging fixation of a comminuted fracture defect in certain sizes of patients, Matis initiated an extensive mechanical testing project with the AO Research Institute (ARI) in Davos. In an unstable defect model, which simulated a bridging fixation, 18 different types of AO plates were tested under bending and torsion loads until plastic deformation began. From the data obtained, the bending and torsion stiffness as well as the loads at the elastic limits were determined [77]. Minimally invasive osteosynthesis techniques also gained in popularity among AOVET members. However, these techniques are easier to apply in small animal surgery than in equine patients. When in 1984 the AO modified its organizational structures, becoming the AO Foundation (Fig 56) with additional functional groups, the AOVET became an integral part of this Foundation.

Fig 56 The birth of the AO Foundation in 1984: left to right, top of table: Peter von Rechenberg, CEO; front row: Martin Allgöwer, Maurice Müller, Robert Schneider, Hans Willenegger; back row: Thomas Rüedi, Peter Matter, Fritz Straumann, Robert Mathys, Stephan Perren, Hans-Jörg Wyss.

9â&#x20AC;&#x201A; Consolidating the achievements of the AOVET founders

Con

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9 Consolidating the achievements of the AOVET founders

After the untimely death of Fritz Straumann, the support of the veterinarians in Waldenburg was continued by his son Thomas Straumann and Ortrun Pohler. Soon a management buyout occurred and Ruedi Maag took over the orthopedic section of the Straumann Institute and renamed it Stratec Medical, while Thomas Straumann continued to lead the dental implant section that remained under the name of Straumann Institute. With this, the support Straumanns had given to AOVET and the AOVET Center was lost. When Dieter Prieur retired as executive secretary of AOVET at the end of 1991, the AOVET Center was moved from Waldenburg to the Veterinary Surgery Clinic at the University of Zurich, Fig 57 Monika Gutscher started her new job with AOVET which was directed by Jörg Auer who returned from the US November 1, 1991, and took over in 1989 to take over as Professor of Veterinary Surgery. His as secretary after the AOVET decision to return to his alma mater was also influenced by Center moved from Waldenburg to Zurich. his desire to be more involved with the AO Foundation, a wish that became true shortly after his arrival in Switzerland when he was elected as successor of Dieter Prieur. The leadership of the AO Foundation was happy to see the AOVET Center being strongly supported by the leader of a Swiss university clinic and offered generous financial support, which included the employment of a secretary for AOVET at the executive secretary level. It was understood from the beginning that working at the AOVET Center did not keep the secretary 100 % busy and that she could accept work related to other business deemed appropriate by Professor Auer, while being paid fully by the AO Foundation. This was seen as a win-win situation, by having AOVET affiliated with an academic institution and with that institution profiting from AO Foundation. For the secretary role, Professor Auer knew of a school friend of his wife, who was involved in hotel management and was returning home to Switzerland after opening the Swisshotel in Beijing, China. Monika Gutscher (Fig 57) was looking for a job in Switzerland and when Auer asked her if she would be interested in something new and exciting, she accepted. Gutscher was the right person because of her management and language skills. For her, it was appealing as she did not have to work evenings or weekends, as in the hospitality industry. It was clear that she needed to familiarize herself with the medical terminology. To prepare for her new job, Monika started to work for AOVET on November 1, 1991. She learned quickly and was accepted by everybody. She

participated in the Davos Courses the following month, which allowed her to get to know many of the AOVET and AO Foundation members. Soon she was asked to be part of the front desk team at the Davos Courses. In 1979, AOVET had been placed under the supervision of AO International and continued to be a member after the AOVET Center moved to Zurich. In 1992, AO International was directed by Professor Peter Matter and later by Professor Thomas Rüedi. As a member of AO International, the AO Foundation started to support AOVET financially and gradually increased the financial support. Full financial responsibility of AOVET through the AO Foundation that started on January 1, 1992, with the move to Zurich, came about through the AOVET Center. Therefore, the executive secretary and his secretary turned in the budget and allocated all the funds. The AOVET Association itself was only responsible for the money gathered through the yearly membership fees. These funds were accumulated unless a special cause was proposed by the AOVET board and voted on by the membership. The AOVET Center team got involved in the organization of AOVET courses, first mainly in Europe. Through Dieter Prieur’s efforts good connections were established with various universities across Europe and with time, yearly courses were organized in France, Italy, Austria, and Germany. Other countries followed and these arrangements were continued after the move of the AOVET Center to Zurich. The courses offered in OSU were integrated into AOVET’s annual course plan and slowly the courses expanded to Latin America and Asia Pacific. In 1992, Auer was elected as chair of the Veterinary Technical Commission (TK), which was later renamed the Veterinary Expert Group (VEEG). Through this he was elected as an ex officio member to the Board of Trustees of the AO Foundation. Being part of the executive office of the AO Foundation led to good connections with the leaders of the Foundation across the world. Slowly the stature of AOVET rose and with the help of the President of AO International, Professor Peter Matter representation of AOVET on the Board of Trustees was doubled by granting the President of AOVET an additional ex officio membership. This increased representation was a big advantage in moving forward the AOVET cause for official recognition.

9 Consolidating the achievements of the AOVET founders

Unfortunately, there was inadequate recognition of AOVET from Stratec Medical and Mathys Inc. Only Synthes USA actively supported AOVET aside from the AO Development Institute. Despite these facts, Ortrun Pohler, who continued to work for Stratec Medical following the management buyout that occurred after Straumann’s death, supported AOVET whenever possible. To be fair, it has to be kept in mind that the producers were under constant pressure to produce an adequate amount of implants, instruments, and new developments to satisfy the rapidly expanding human market, which resulted in a less than optimal support for AOVET. At each trustee meeting Jörg Auer was asked to report on the activities of the AOVET TK but in most instances the meeting ran behind schedule, so that he was asked to keep it short. On most occasions he did that, except in 1996 in Gleneagles, Scotland. When he was asked by the moderator to “keep it short,” Auer went to the podium and told the audience that he was about to use all of his allotted 15 minutes of speaking time. During his presentation he pointed out all the achievements AOVET had contributed to the AO Foundation. He also mentioned that the veterinarians were only supported by Synthes USA and that Mathys AG and Stratec Medical no longer contributed to the development of new implants and instruments. At the end of his presentation he posed the key question to all trustees: “Do you want AOVET to continue to be part of the AO Foundation?” He added that if the answer was “yes, we want AOVET to continue,” then it must also be properly supported in the future. On the other hand, if the answer was “no,” AOVET would quietly pack its bags and leave the AO Foundation. The trustees responded to this question with a unanimous standing ovation. As an immediate reaction to this presentation, AOVET representation on the Board of Trustees was increased, with the President-Elect becoming an ex-officio member during his/her 2-year term, followed by a 2-year term as President and ending after the first year as Past President, resulting in a 5-year membership on the Board of Trustees. The increased number of AOVET members on the Board of Trustees resulted in better visibility and better acceptance of the “fledgling” but “oldest” clinical division within the AO Foundation. Shortly afterward Jörg Auer was elected to the Academic Council. During the Schatzalp II Specialty Reorganization project, AOVET was officially

voted in as one of the four AO Foundation clinical divisions, along with AOTrauma, AOSpine, and AOCMF. The last piece of the puzzle was added at the Trustee Meeting in Chicago in 2009 when the membership had to vote on the new bylaws. These bylaws contained a provision that the Chairpersons of all the clinical divisions were also members of the Board of Directors (AO Verwaltungsausschuss—AOVA); however, the Chairperson of AOVET was not included. Chris Colton, a Past President of the AO Foundation, noticed this discrepancy, which was also obvious to all veterinarian trustees, and he proposed that the Chairperson of AOVET also be included as a member of the AOVA. This proposal was subsequently accepted unanimously together with the new bylaws. Therefore, Jean-Pierre Cabassu (Fig 58), Chairperson of AOVET and an esteemed small animal practitioner from Marseille, France, became the first AOVET member to be a member of the AOVA, a supplementary duty that he had not planned on when he accepted the nomination to be Chairperson of AOVET a few months earlier. Nevertheless, he fulfilled his term on the AOVA very successfully, earning the full respect of his fellow AOVA members.

Fig 58 Dr Jean-Pierre Cabassu with his family left to right: Julien, also a specialist veterinary surgeon, Beatrice, his wife and veterinary ophthalmologist, Laurent, Jean-Pierre, and Antoine.

9 Consolidating the achievements of the AOVET founders

Being accepted as an equal among the clinical divisions led to a complete restructuring of AOVET according to the guidelines established in the other clinical divisions and a substantial increase in the annual budget. At that time the VEEG membership consisted of three small animal and two equine veterinarians. Most activities within the VEEG dealt with new implants for small animals but it was important not to forget the few projects supported by the equine members. It was the duty of the VEEG chair to assure adequate time for both groups. With the acceptance of AOVET as the fourth clinical division and increased funds, it was possible to get more members involved in key positions. Therefore, in 2008 Jörg Auer passed the leadership of the VEEG on to Professor Jeffrey Watkins (Fig 59) of Texas A&M University, again an equine specialist. He established himself as an objective VEEG Chairperson, one who could listen to different arguments and suggest solutions that could be accepted by all members. He was the right choice, despite the fact that it was again an equine specialist that led the VEEG.

Fig 59 Professor Jeffrey Watkins during the practical exercises of the Equine Course in 2004. He took over leadership of the VEEG in 2008. He presently still acts as Chairperson of the joint Equine and Small Animals subgroups, a demanding task.

With the reorganization of the AO TK, the other three clinical divisions could establish their own TKs. However, the VEEG was assigned to the AOTrauma TK. In addition one small animal and one equine member were added to the VEEG. In 1999 Synthes USA took over Stratec Medical and formed the company Synthes-Stratec headquartered in Waldenburg. In 2003 Synthes-Stratec and Mathys AG completed their merger. Subsequently, the company acquired the Synthes trade name and was from then on named Synthes Inc with its headquarters in Solothurn, Switzerland. The company established contracts with the different clinical divisions and it was decided that AOVET needed to organize at least eleven courses per year. Ever since that decision the number of courses organized by AOVET rose continually to the present number of more than 26 worldwide courses. Initially, the courses were mainly concentrated in Europe and the US but recently AOVET has expanded the course organization into Latin America and Asia Pacific. In the future, the number of courses offered in these regions, particularly in Asia Pacific, has to be expanded while the number of courses offered in Europe may have to be reduced, especially if funding cannot be significantly increased. In 2005 Hansjörg Wyss, owner of Synthes Inc, reacted favorably to the request of the AOVET Trustees during the Trustee Meeting in Venice and established a special unit dealing only with veterinary issues, specific veterinary instruments and implants, many of which were identical to their human counterparts but equipped with special veterinary order numbers—SynthesVET. This unit works closely with the VEEG, a section of the AO Trauma TK-System, in developing new implants and instruments. Since 2009, which marked its 40-year anniversary, AOVET is fully recognized and viewed as an equal, valuable partner in the AO Foundation’s daily activities. We all look forward to a joint and mutually successful future.

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10 Special events

Since the early years of AOVET Courses in Davos, one event remains a special tradition even today: the AOVET fondue party! It was Geri Kása’s original idea to create an event where the faculty and the course participants could get to know each other a little better. The fondue party was a great success from the beginning (Figs 60 and 61). When Jörg Auer and Monika Gutscher took over the reins of the AOVET Center, this tradition was continued and expanded over the years. Some AO Foundation members, AO Research Institute staff, AO Foundation staff, Synbone staff, and friends of AOVET were invited to the AOVET fondue party. Another tradition gradually developed where Jörg Auer presented fun gifts to selected participants (Fig 62). Every year the AOVET fondue party is always held on the evening of the first course day. Traditionally, the AO Foundation President participates, Chris van der Werken called the AOVET fondue party the “real”, official opening of the Davos Courses, a self-explanatory and justified expression. In 1999, the 30-year AOVET Jubilee was celebrated with a special dinner at the Hotel Flüela (Fig 63). During the evening, Björn von Salis, Feri and Geri Kása, and Dieter Prieur were honored as Honorary AOVET Members. In 2009, a similar party was held to celebrate 40 years of AOVET.

Fig 60 Geri Kása (left) who introduced the AOVET Fondue Party during the Davos AOVET Courses, at one of the first such events. Joining her are Ortrun Pohler (middle) and Fridolin Séquin (right).

Fig 61 Björn von Salis celebrating the tradition of the AOVET Fondue Party.

Fig 62 Jörg Auer presenting a bottle of premium Italian wine called No. 1 (nummero uno in Italian) to two number 1s during the 2004 AOVET Fondue Party: AO Foundation President James Kellam, and newly installed CEO of Synthes Inc. Michel Orsinger.

Fig 63 Some of the participants of the 30-year AOVET celebration in 1999 at the Hotel Flüela; Davos, left to right: front row: Jörg Auer, Cathrin von Salis, Björn von Salis, Uschi Nunamaker, David Nunamaker; middle row: Peter Dätwyler, Geri Kása, Urs Guggenbühl, Rosemarie Widmer, Ortrun Pohler; back row: Roberto Köstlin, Feri Kása.

10 Special events

The American Association of Equine Practitioner (AAEP) bestowed the “Distinguished Educator Award” (Fig 64) to AOVET in recognition of its pronounced impact on teaching fracture management in horses around the world. During its 2003 Annual Meeting in San Francisco, California, Auer personally accepted this award from the AAEP President, Tom Lenz (Fig 64). Brigitte von Rechenberg, the daughter of the first AO Foundation CEO and frequent faculty member of early AOVET small animal courses, was instrumental in organizing the Biotechnology Advisory Board (BAB) of the AO Foundation in 2003. The BAB was responsible for evaluating novel technologies that were important to the AO Foundation. It consisted of top-level scientists across the world—including one veterinarian (David M Nunamaker of the University of Pennsylvania) and set the stage for modern evidence-based research in the AO Foundation. Because of her exceptional visionary input, von Rechenberg was honored with the TKRecognition Prize at the 2004 Davos Courses (Fig 65).

Fig 64 The American Association of Equine Practitioners (AAEP) presents its “Distinguished Educators Award 2003“ to AOVET. Jörg Auer accepts the award in the name of AOVET from AAEP President Dr Tom Lenz.

Fig 65 Dr Brigitte von Rechenberg (left) receiving the Recognition Prize of the Technical Commission in 2003, while Urs Jann, Secretary of the AO Foundation was installed as Honorary Member of AO Latin America.

During the 50-year Golden Jubilee celebration of AO in 2008, the AO Foundation bestowed its Recognition Prize on Jörg Auer for his “outstanding achievements on behalf of the AO Foundation” (Fig 66). Up to then, this prize had been awarded to a total of seven recipients, either research groups or individuals, all of which belonged to the clinical divisions for human medicine. For the 50-year Celebration of the AO Foundation during the Trustees Meeting in Davos in 2008, all the past presidents of AOVET and their spouses were invited. It was very refreshing to meet with our former and present leaders and discuss all the changes that have occurred over the past 39 years. Unfortunately, David Nunamaker could not participate. Aside from the two past presidents who have left us forever, Wade Brinker and Bruce Hohn, all other past presidents were present (Fig 67).

Fig 66 AO Foundation President Chris van der Werken (left) and Chairperson of the Technical Commission Norbert Haas (right) presented Jörg Auer with the “AO Recognition Prize” (the highest award of the AO Foundation) during the 50-Year-Jubilee Trustee Meeting in Davos 2008.

Fig 67 AOVET past presidents and participants at the 50-Year AO Foundation Celebration in Davos during the Trustees Meeting 2008; left to right: Ken Johnson, 2002–2004; Geoffrey Sumner-Smith, 1986–1988; Don Piermattei, 1990–1992; John Houlton, 2000–2002; Gary Clayton Jones, 1988–1990; Ulrike Matis, 1996–1998; Michel Baron, 1992–1994; Donald Hulse, 2006‒2008; Rico Vannini, 2004–2006; Jean-Pierre Cabassu, 2008–2012; Jeffrey Watkins, Chair VEEG, Jörg Auer, Executive Secretary; Björn von Salis, founding president 1969–1980; Frerenç Kása, founding member; Urs Guggenbühl, founding member.

11â&#x20AC;&#x201A;Epilogue

Epilo

gue

11â&#x20AC;&#x201A;Epilogue

In general, this short history of AOVET has been structured chronologically. This may vary in order to maintain the continuity of certain processes or tendencies; however, this should not be interpreted as errors in the text. To give a flavor of the early pioneering days of AOVET, the corresponding sections are longer and casual in content compared with other sections. Some of the very early history of the AO is mentioned to highlight AOVETâ&#x20AC;&#x2122;s background and to illustrate the similar driving forces behind the creation of both organizations. The publications referenced are limited; manuals are listed to provide sources of information to those interested. Other publications cited in the text were selected to show the state of the art within a certain time frame. With much regret it must be noted that it was not possible to include more of the extensive veterinary literature related to orthopedic surgery and fracture treatment in the reference list. Unfortunately, given the text limitations it was also not possible to mention all AOVET members who contributed in friendship and with enthusiasm to the development of AOVET. Many good memories are connected with our membership past and present, without them the establishment of AOVET would not have taken place.

AOVET Presidents 2008−2012 Cabassu Jean Pierre France SA 2006−2008 Hulse Donald United States SA 2004−2006 Vannini Rico Switzerland SA 2002−2004 Johnson Kenneth United States SA 2000−2002 Houlton John United Kingdom SA 1998−2000 Nunamaker David United States LA 1996−1998 Matis Ulrike Germany SA 1994−1996 Olmstead Marvin United States SA 1992−1994 Baron Michel France SA 1990−1992 Piermattei Don United States SA 1988−1990 Clayton Jones Gary United Kingdom SA 1986−1988 Sumner-Smith Geoffrey Canada SA 1984−1986 Hohn Bruce † United States SA 1982−1984 Meutstege Freek Netherlands SA 1980−1982 Brinker Wade † United States SA 1969−1980 von Salis Björn Switzerland LA

LA = large animal practitioner SA = small animal practitioner

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