What’s the Diagnosis – Case 129
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What’s the Diagnosis – Case 129
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What’s the Diagnosis – Case 129
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What’s the Diagnosis – Case 129
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What’s the Diagnosis – Case 129
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What’s the Diagnosis – Case 129
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What’s the Diagnosis – Case 129
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What’s the Diagnosis – Case 129
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What’s the Diagnosis – Case 129
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What’s the Diagnosis – Case 129
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What’s the Diagnosis – Case 129
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Findings The patient has undergone a total shoulder arthroplasty via reverse type prosthesis. At the one year follow up there is a radiolucency at the inferior border of the scapula neck/glenoid. Over time this may progress somewhat until the radiographs of 2017. The degree of lucency and bone resorption is seen well on the CT study where it extends superiorly from the scapula to cause a defect about the central post/screw. Note is made of the positioning of the glenoid about the middle to superior aspect of the glenoid and an almost neutral tilt.
What’s the Diagnosis – Case 129
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What’s the Diagnosis – Case 129
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What’s the Diagnosis – Case 129
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What’s the Diagnosis – Case 129
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What’s the Diagnosis – Case 129
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What’s the Diagnosis – Case 129
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What’s the Diagnosis – Case 129
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Diagnosis: Scapular Notching One of the unique complications of the reverse total shoulder arthroplasty is scapular notching related to the impaction of the medial aspect of the humeral component/polyethylene along the inferior border of the scapula with shoulder adduction. The process is thought to relate not only to mechanical wear but polyethylene wear engendering an even greater degree of bone resorption. The concept has been a matter of debate for many years but with most in present day feeling that notching does correlate with increased pain and decreased performance. The grading/classification was described by Sirveaux and progresses from bone wear of the so called scapular pillar, to the inferior screw, involvement of the entirety of the inferior screw, and then involving the central screw/post or the metaglene/baseplate. Progressed degrees of notching are thought related to a greater possibility of glenoid loosening and poorer clinical outcomes. Great efforts over the last decade have been made to try and understand how to better implant/design this prosthesis. Because of notching there is now a greater lateralizing of the center of rotation of the prosthesis and the metaglene/base plate are now placed at the far inferior aspect of the glenoid (even with inferior overhang) and with inferior tilt (often approximately 10-15 degrees). Although these changes themselves may have ramifications, at present this is working well. Interestingly as in this case when notching is seen it is often found early after the index procedure within a couple of months to one year. However, it frequently shows little progression after many years of follow up although some authors have shown substantial progress over years follow up. As there is little in terms of how to direct surgeons in the management of scapular notching, although this patient is limited she is opting for no additional surgery at this time. What’s the Diagnosis – Case 129
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References Scapular Notching in Reverse Total Shoulder Arthroplasty. Friedman RJ, Barcel DA, Eichinger JK.J Am Acad Orthop Surg. 2018 Sep 26. doi: 10.5435/JAAOS-D-17-00026 Scapular Notching: Recognition and Strategies to Minimize Clinical Impact. Gregory P. Nicholson, Eric J. StraussSeth L. Sherman. Clinical Orthopaedics and Related Research. September 2011, Volume 469, Issue 9, pp 2521–2530 Grammont inverted total shoulder arthroplasty in the treatment of glenohumeral osteoarthritis with massive rupture of the cuff. Results of a multicentre study of 80 shoulders. Sirveaux F1, Favard L, Oudet D, Huquet D, Walch G, Molé D. J Bone Joint Surg Br. 2004 Apr;86(3):388-95.
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