title: The use of a modular system to convert an anatomical total shoulder arthroplasty to a reverse shoulder arthroplasty: Clinical and radiological results.
abstract: If a modular convertible total shoulder system is used as a primary implant for an anatomical total shoulder arthroplasty, failure of the prosthesis or the rotator cuff can be addressed by converting it to a reverse shoulder arthroplasty (RSA), with retention of the humeral stem and glenoid baseplate. This has the potential to reduce morbidity and improve the results. In a retrospective study of 14 patients (15 shoulders) with a mean age of 70 years (47 to 83) we reviewed the clinical and radiological outcome of converting an anatomical shoulder arthroplasty (ASA) to a RSA using a convertible prosthetic system (SMR system, Lima, San Daniele, Italy). The mean operating time was 64 minutes (45 to 75). All humeral stems and glenoid baseplates were found to be well-fixed and could be retained. There were no intra-operative or early post-operative complications and no post-operative infection. The mean follow-up was 43 months (21 to 83), by which time the mean visual analogue scale for pain had decreased from 8 pre-operatively to 1, the mean American Shoulder and Elbow Surgeons Score from 12 to 76, the mean Oxford shoulder score from 3 to 39, the mean Western Ontario Osteoarthritis of the Shoulder Score from 1618 to 418 and the mean Subjective shoulder value from 15 to 61. On radiological review, one patient had a lucency around the humeral stem, two had stress shielding. There were no fatigue fractures of the acromion but four cases of grade 1 scapular notching. The use of a convertible prosthetic system to revise a failed ASA reduces morbidity and minimises the rate of complications. The mid-term clinical and radiological results of this technique are promising.
authors.affiliation: Hannover Medical School, Carl-Neuberg-Str. 1, D-30625 Hannover, Germany.
authors.forename: T S
authors.initials: TS
authors.lastname: Weber-Spickschen
authors.affiliation: Hannover Medical School, Carl-Neuberg-Str. 1, D-30625 Hannover, Germany.
authors.forename: D
authors.initials: D
authors.lastname: Alfke
authors.affiliation: Go:h (Gelenkchirurgie Orthopädie Hannover), Uhlemeyerstraße 16, 30175 Hannover, Germany.
authors.forename: J D
authors.initials: JD
authors.lastname: Agneskirchner
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D019643:Arthroplasty, Replacement / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007595:Joint Prosthesis; D008297:Male; D008875:Middle Aged; D010003:Osteoarthritis / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery*; D011474:Prosthesis Design; D011859:Radiography; D016059:Range of Motion, Articular; D012189:Retrospective Studies; D017006:Rotator Cuff / Q000601:surgery; D012785:Shoulder Joint / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery*; D016896:Treatment Outcome
keywords: Conversion; failed anatomic shoulder arthroplasty; failed fracture prosthesis; failed hemiarthroplasty; midterm; modular system; outcome; reverse shoulder arthroplasty; revision shoulder arthroplasty