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SCHOLARLY PAPER
Implementation of Exercise Programmes for Prevention and Treatment of Low Back Pain Bill Tancred Geoff Tancred Key Words Low back pain, exercise programmes, range of motion, flexibility, prevention, general fitness.
Summary This article attempts to review the literature supporting the beneficial role of exercise in the prevention and treatment of low back pain. Provided certain considerations are applied, findings overwhelmingly advocate the use of exercises in the treatment of such afflictions. Various exercise considerations are also described together with their significance in planning successful treatment. Principles governing the design of exercise programmes are also offered with a view to making the treatment procedure as effective as possible. A distinction between health and skill-related fitness is also exDlained.
Introduction The many methods of diagnosis available in determining the various types of low back pain (LBP)are diverse. On careful analysis and consideration of the anatomy of the vertebral column, the structural intricacies of its component parts and its variety of functions, it is clear t h a t the causes of backache can result from many forms of dysfunction. The causes of LBP are numerous and in part due t o a n ever-increasing sedentary lifestyle, less physical activity among young people aQd adults, convenience of modern living, overweight and obesity which contributes t o extra stress on the spine, poor postural habits, poor body mechanics in working procedures (ergonomics), certain repetitive motions, and the unavoidable accident or trauma-induced injury to the back (Fryomoyer and Cats-Baril, 1991; Kottke, 1982; Cailliet, 1982). Any or all of these factors contribute to the wear and tear of the structures of the spine t h a t may lead to LBP or injury to the back. LBP is, therefore, a complex and multifaceted problem. People suffering from LBP will often be affected physically, psychologically, economically, socially and recreationally. Hence, the effectiveness of treatment is a n important aspect in alleviating these affects.
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The omnipresence of spinal disorders in various populations has been well documented (Anderson, 1981; Gilula, 1981; Stoddard, 1969; Torgerson and Dotler, 1976; Troup et a l , 1981). Anderson (1981) indicates t h a t 50% t o 80% of all adults will suffer from back pain during their lifetime.
It is clear that the treatment of LBP is a difficult task when taking into account the numerous techniques and applications that are now available. While appreciating the vast scope of treatment protocols in general use for LBP the focus in this article is on exercise. Regular exercising can have many beneficial rewards to the individual and is perhaps a n area which does not always have the same emphasis as other forms in the overall treatment strategy (Davies et a l , 1979; Tollison and Kriegal, 1988). This is perhaps due to the specialisation required in selecting and performing appropriate exercises leading t o recovery and restoring well-being. More recently, however, Lamb and Frost (1993) criticised the standard and frequency of exercise therapy in general, while Norris (1995a) asserted that exercise therapy is a specialist clinical skill and a key tool in restoring patients’ well-being. An important consideration for the clinician is the ability to select accurate, valid and reliable tests of functional capacity so t h a t specific exercise needs can be identified. Based on the above factors and patients’ needs, exercises must be selected and recommendations made with regard to their frequency, intensity, time (duration) and type - the FITT principle (table 1). Table 1: The FITT principle F - Frequency: How often per week can or should the patient exercise? I - Intensity: How energetically or vigorously should the patient exercise? T - Time: How long should the patient exercise to obtain benefits? T -Type: What kind of exercises should be prescribed for the patient?
The implementation of the FITT principle will depend on a number of factors which would include the severity and nature of a patient’s LBP, age, body build, current ‘fitness’ status, personality make-up and motivation. On selecting appropriate exercises, monitoring measures should evaluate the effectiveness of t h e chosen exercises and determine whether the patient is fit to return to work, home and/or sport.
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Prophylactic Measures ‘Prevention is better than cure’ is a term commonly believed and thought important by health professionals. With greater education and public awareness, attempts have been made t o decrease the severity and incidence of LBP through such organisations as the Health Education Authority with its ‘Look after yourself project (19941, and the Health and Safety Executive (HSE, 1992, 1994). Nevertheless, certain people may be predisposed to LPB, therefore the identification of such individuals could be useful. Those at greater risk of LBP may exhibit one or more of the characteristics shown in table 2. Table 2: Predisposing factors for low back pain (Kraus, 1972) ~
~
Excess weight Extreme lordosis Absence of regular exercise Weak abdominal muscles Tight hamstrings or hip flexors Weak or tight back muscles General muscular tension
Individuals who suffer from LBP demonstrate several forms of physical deficiency that warrant the use of exercise in such treatment (Kraus, 1972). They typically lack sufficient levels of muscular strength, flexibility and endurance in the muscles of the lumbar spine, abdominals and pelvis (LaRocca and Nachemson, 1987). Pollock and Wilmore (1990) claim that such individuals are often in poor general condition and overweight. The aim of exercise prescription in the treatment and prevention of LBP should therefore be t o improve and/or correct these deficiencies. Posture also plays a role in the prevention or causation of LBP, particularly when lifting and transporting objects (HSE, 1992, 1994). In many instances, the incidence of LBP may be lowered after employees are trained to use proper lifting techniques (Magora, 1970; HSE, 1992). The former also found a higher incidence of LBP in people who either sat for prolonged periods o r were unable t o sit at all during the working day. There is a need, therefore, for employers and employees t o avoid situations of prolonged unchanged posture and t o appreciate the importance of good body mechanics while standing or sitting. Anderson (1981) noted that sitting in bent-over work postures increased the risk of LBP, and stressed the importance of changing posture while working. It is evident that the severity or incidence of LBP can be eased t o a large extent through preventive measures o r early intervention in such
conditions that may predispose t o LBP as indicated in table 2. In such situations, the values and benefits of regular exercise programmes become more evident in helping reduce the onset and severity of LBP (Davies et al, 1979; Pollock and Wilmore, 1990).
Exercise Programmes Gowers (1904) is often credited as being the first t o recognise the importance and value of physical activity in the treatment and prevention of LBP. He suggested that lumbago and muscular rheumatism in general could be cut short at its onset by active exercises. He indicated that the treatment then available for LBP was counterirritation of the lumbar extensor muscles and hypodermic injections of cocaine, repeated daily for between two and three weeks. Because this range of treatment was so limited, the suggestion of exercises was welcomed. Subsequently, exercises have played a crucial role in the treatment of LBP as well as other clinical ailments. Therapeutic exercise essentially is the prescription of bodily movements or muscle contractions t o correct an impairment, improve musculoskeletal function or maintain a state of wellbeing (Kottke, 1982). Designing therapeutic exercise prescription programmes for the treatment and prevention of LBP (Liemohn et a l , 1988) requires careful consideration of numerous factors. A sound knowledge of the various causes of LBP is necessary, as is an understanding of the specific role exercises have in treating such afflictions. Exercises and activities should be useful as therapeutic modalities if they are defined, analysed and classified according t o Cynkin (1979). Farfan (1975) and Floyd and Silver (1955) have stressed the importance and value of spinal muscular strength in providing support and stability t o the lumbar spine. More recently, Graves et al (1989) and Pollock et al (1989) focused much attention on the use of exercise in the development and maintenance of strength in the lumbar extensor muscles. There is a great variety of clinically used exercises that are advocated in the treatment of LBP. However, some have serious drawbacks that may limit their effectiveneness (Pollock et a l , 1989) when treating LBP patients (contra-indicated exercises). Likewise, Lamb and Frost (1993) are critical of exercise therapy in general. Therefore, the selection and manner in which specific exercises are performed must be given serious consideration, along with careful assessment and observations at all times.
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All-round Fitness Many agree that risk of injury and LBP is reduced to some extent if the level of fitness is increased. Such a claim is supported by Cady and Bischoff (19791, whose study involved the relationship between prior levels of physical conditioning and the frequency of subsequent back injuries involving 1,652 firefighters. Five measures of physical fitness and conditioning (three for cardiovascular fitness and one each for strength and flexibility) were used t o categorise subjects into three groups according to their fitness level. Their findings revealed that the frequency of back injury was ten times greater for the least fit group than for the most fit group. Cady and Bischoff (1979) concluded that increased fitness protects against LBP to a significant degree. Cady and Bischoff (1979) firmly established the need for exercise and general fitness in combating injury and LBP. Jackson and Brown (1983b) and Tollison and Kriegal (1988) also recommended exercise t o achieve a greater level of fitness in patients with LBP. In view of such support for exercise in the treatment of LBP, the relative importance of overall fitness in relation to the treatment and prevention of LBP should be reviewed in proper context. Treatment for most neuromuscular and musculoskeletal injuries generally involves exercise to increase strength and flexibility of muscles and other soft tissues involved in joint function. The treatment of LBP should be no exception. The purpose, therefore, of achieving greater levels of general fitness should be viewed as secondary to the aim of restoring and maintaining adequate function of the lumbar spine. The various ‘s’ factors of stamina, strength, suppleness, specificity, speed, skill, and psychology, along with co-ordination, should form the basis of a rehabilitation exercise programme. This will allow for a balanced and varied programme to be devised. These ‘s’ factors are described more fully by Norris (1995a) who also cites the possible consequences of imbalance when focus is placed only on isolated ‘s’ factors t o the exclusion of others. The concept of fitness is sometimes sub-divided into health related fitness (HRF)and skill related fitness (SRF)as depicted in the figure. The factors indicated in these two components should also be considered when devising an exercise programme to suit a patient together with the ‘s’factors. The various ‘s’factors and HRF and SRF components are too numerous t o review in detail, but nevertheless should be viewed in their entirety when devising an exercise programme for the prevention and treatment of LBP. However, the
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Body composition Strength
Flexibility
Health related fitness
1
Lung efficiency
I Muscular Cardiovascular fitness
endurance
Reaction time
I
Agility
Co-ordination I
I
Skill related fitness Speed
Power
Balance
Health and skill related fitness
concept of flexibility (suppleness) will be described in its importance t o LBP to provide an example of how the other aspects of fitnesshealth may be approached.
Flexibility Flexibility is joint specific and is the ability to move through a range of motion (ROM). The extent of ROM depends on several specific variables, including distensibility of the joint capsule, muscle temperature, muscle viscosity, muscle weakness, adhesions of scar tissue and flexibility of ligaments. Any of these can affect the spine. The assessment of flexibility has been extensively reviewed by Corbin (1984). The ROM can serve several purposes (table 3). Table 3: Purposes served by ROM Determine limitations that interfere with function or may produce deformity (eg poor posture). Determine additional range needed to increase functional capacity or reduce deformity. Keep a record of progression (or regression). Measure progression objectively. Determine appropriate treatment goals. Select appropriate treatment modalities, positioning techniques and other strategies to reduce limitation. Determine the needs for splints or other devices.
All exercises, regardless of their nature and purpose, should be performed with quality of movement (ie skill) so that control and safety remain paramount. In relation t o LBP this is supported by Waddell (1987) who claims that controlled exercises help in restoring function, reducing distress, and promoting a n earlier return t o work. Further support for motor and
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muscle control in LBP is provided by Jull and Janda (1987). The need for adequate levels of flexibility in the various muscles of the trunk and pelvis are important considerations. Farfan (1975) claims that the flexibility of the lumbar spine provides a mechanical advantage for function and efficacy. Shortened muscle structures due t o poor ROM may adversely affect spinal mechanisms, thus resulting in possibly increased loads on the spine. Bach et aE (1985) consider pelvic mobility to be essential in lifting and bending activities. They also report that tightness in the hip flexor muscles could limit pelvic movements so much that it could cause excessive strain on the lumbar spine. Likewise, according to Bach et aZ(1985),tightness in the hip extensor muscles could eventually result in a reduction of the lumbar lordotic curve, making the spine less resilient to axial loadings. Individuals with LBP generally show a significant limitation in ROM during various movements of the trunk and pelvis, usually accompanied by tight hamstrings (Farfan, 1978). Compared t o healthy individuals, people with LBP demonstrate decreased levels of ROM in trunk flexion and extension according t o Smidt et al (1983) and Lagrana et aZ (1984). Smith (1977) found those afflicted by LBP had decreased levels of ROM in hip flexion and extension. From the above findings, it can be deduced that exercise to increase o r maintain flexibility of the trunk and pelvis regions is essential in the treatment and prevention of LBP. However, Jackson and Brown (1983a), Kirkaldy-Willis (1990) and Panjabi (1992) offer caution in that too much mobility may excessively load the spine, overstrain o r compress pain sensitive structures, o r cause inflammation, potentially exacerbating the development of low back disorders. Care must therefore be taken against overtraining for this component of fitness. Generally, joints should only be worked through their pain-free ROM, according t o Kottke (1982). Weak muscles should not be overstretched when exercised, otherwise they will function less effectively (Kraus, 1972). Excess fatigue of muscles should also be avoided (De Vries, 1968). These principles also apply generally to other muscle groups and joints of the body.
A question also arises over hypermobility and stabilitylinstability of the lumbar spine when discussing flexibility. This aspect is adequately explained by Norris (1995a) who also offers a comprehensive discussion on lumbar stabilisation through an exercise programme (Norris, 1995b).
Exercise Prescription An exercise programme is a personalised regimen of recommended physical activity, specifically and systematically designed. The programme should indicate clearly the mode, frequency, intensity, time (duration) and type (FITT principle -table 1) of exerciselactivity and the progression monitored closely. This approach can be applied regardless of age o r functional ability, following careful consideration of the individual’s health history, risk factors, behavioural characteristics, motivation and personal goals. Other factors also need to be considered when activities and exercises are selected for therapeutic purposes (Hopkins, 1978) and are shown in table 4. Table 4: Factors required when selecting therapeutic exercises (adapted from Hopkins, 1978) ~~
~
The exercise programme must: Be goal directed. Have some significance and relationshipto the patient’s individual needs. Require the mental and/or physical participation of the patient. Be designed to prevent or reverse dysfunction. Develop skills to enhance performance in life roles. Relate to the patient‘s interests. Be adaptable, gradable and age appropriate. Be selected through knowledge and professional judgement in concert with the patient.
The specific purposes of an exercise programme will vary among individuals, depending upon their interests, needs, backgrounds and current health status, and whether the purpose is t o enhance or maintain general health, prevention or treatment, rehabilitation or relief of pain. The application of the SMART principle will help when devising a n exercise programme t o the needs and support of the patient (table 5). Table 5: The SMART principle S - Specific to the patient and with specific objectives that are action or exercised based. M - Measurable, so the progress of the patient can be monitored, evaluated and maintained. A - Action-based, so that the selection of exercises meets the patient’s needs. R - Realistic, to enable the patient to achieve the targets set. T - Time-based: specific to the patient both in the short and long term
All these purposes should carry equal weight for any exercise programme, whether for a healthy or injured individual. The major aims of an exercise programme for LBP patients is essentially twofold: t o counteract any detrimental effects following bedrest andlor pfevious sedentary lifestyle patterns, and t o maximise the patients’ functional capacity within the
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physiological and anatomical limitations of their affliction. An exercise sequence may have to be modified or evaluated entirely if expectations of its effect and impact are not fulfilled o r complications arise early in the programme. These are shown in table 6.
Authors Bill Tancred MBE PhD is principal lecturer at Buckinghamshire College of Higher Education. Geoff Tancred MCSP DipRGgRT is a consultant in health and fitness for industry. This article was received on May 12, 1995, and accepted on January 16, 1996.
Address for Correspondence Table 6: Early evaluation during the implementationof an exercise programme Some exercises may prove contra-indicated in some patients. Expected physiological changes and improvements will vary among patients. The exercise programme must lend itself to modification if necessary. An exercise programme may have to be terminated with complete re-evaluation. Exercises should only be started and performed when the patient is clinically stable. Every exercise/activity prescribed must be safely and correctly performed at all times.
These considerations make it difficult t o recommend a specific active exercise prescription schedule because so many variables need to be observed. There might be extensive assessment and the current health status of the individual must be known before exercises can be beneficially prescribed. A well-designed exercise programme with appropriate content will help to foster a n improvement in lumbar strength and flexibility, reduce LBP, and motivate the patient.
Conclusion The potential severity and extent of LBP has been explained. Provision of specific exercise programmes for the prevention and treatment of LBP has also been discussed. Various methods of application of exercises and their effectiveness have been cited from a range of documented research with the general consensus being that exercise helps in the treatment and prevention of LBP. The literature reviewed advocates the use of personalised exercise programmes for the restoration and maintenance of adequate lumbar function. These would include flexibility, stamina, strength, skill, speed and specificity. Various guidelines have been offered for designing personal exercise programmes with a view t o restoring health t o and preventing further complications for LBP sufferers. However, the various considerations cited can also apply to other therapeutic exercise programmes for other clinical conditions. Careful consideration of these guidelines should help t o make the treatment aims of LBP more effective.
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Dr B Tancred, BuckinghamshireCollege, Wellesbourne Campus, Kingshill Road, High Wycombe, Buckinghamshire HP13 5BB.
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in other journals Some of these journals may be available in your hospital library, or photocopies of specific articles may be obtained using inter-library facilities (ask your librarian for details). The CSP is also developing its own resource centre and special physiotherapy journals collection. In case of difficulty photocopies from physiotherapy journals may be supplied by the CSP on request (but please obtain them from libraries wherever possible). A charge will be made by the CSP for this service. Contact: Samantha Molloy, Information Assistant, Education Department, The Chartered Society of Physiotherapy. The figures at the end of each entry are the first and last page numbers
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Clinical Biomechanics 1996, vol 11, no 2, January Mechanical stability of the in vivo lumbar spine: Implications for injury and chronic low back bain. J Cholewicki, S M McGill. 1-15. Mechanical behaviour of hamstring muscles in low back pain patients and control subjects. F Tafazzoli, M Lamontagne. 16-24. Development and evaluation of a scalable and deformable geometric model of the human torso. M A Nussbaum, D B Chaffin. 25-34. Properties of musculus gluteus maximus in above-knee amputees. H Burger, V ValenEiE, C MarinEek, N KogovSek. 35-38. Three-dimensional kinematics of the rearfoot during the stance phase of walking in normal young adult males. L Moseley, R Smith, A Hunt, R Gant. 39-45. The deleterious effect of tetanic contraction on rabbit’s triceps surae muscle during cycle loading. J-S Sun, Y-H Tsuang, Y-S Hang et a/.46-50. Pedal forces produced during neuromuscular electrical stimulation cycling in paraplegics. P Sinclair, G M Davis, R M Smith et a/. 51-57.
Journal of Allied Health 1995, vol24, no 4, Fall Australian physiotherapists’ and occupational therapists’ views on professional practice. L A Nordholm, B J Adamson, R Heard. 267-282.
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