title: Do less medialized reverse shoulder prostheses increase motion and reduce notching?
abstract: BACKGROUND
  Cuff tear arthropathy is the primary indication for total reverse shoulder arthroplasty. In patients with pseudoparalytic shoulders secondary to irreparable rotator cuff tear, reverse shoulder arthroplasty allows restoration of active anterior elevation and painless shoulder. High rates of glenoid notching have also been reported. We designed a new reverse shoulder arthroplasty with a center of rotation more lateral than the Delta prosthesis to address this problem.
  
  
  OBJECTIVE
  Does reduced medialization of reverse shoulder arthroplasty improve shoulder motion, decrease glenoid notching, or increase the risk of glenoid loosening?
  
  
  METHODS
  We retrospectively reviewed 76 patients with 76 less medialized reverse shoulder prostheses implanted for pseudoparalytic shoulder with rotator cuff deficiency between October 2003 and May 2006. Shoulder motion, Constant-Murley score, and plain radiographs were analyzed. Minimum followup was 24 months (mean, 44 months; range, 24-60 months).
  
  
  RESULTS
  The absolute Constant-Murley score increased from 24 to 59, representing an increase of 35 points. The range of active anterior elevation increased by 61°, and the improvement in pain was 10 points. The gain in external rotation with elbow at the side was 15°, while external rotation with 90° abduction increased by 30°. Followup showed no glenoid notching and no glenoid loosening with these less medialized reverse prostheses.
  
  
  CONCLUSIONS
  Less medialization of reverse shoulder arthroplasty improves external and medial rotation, thus facilitating the activities of daily living of older patients. The absence of glenoid notching and glenoid loosening hopefully reflects longer prosthesis survival, but longer followup is necessary to confirm these preliminary observations.
  
  
  METHODS
  Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.
authors.affiliation: Institut de la main, Clinique Jouvenet, 6 square Jouvenet, 75016 Paris, France.
authors.forename: Philippe
authors.initials: P
authors.lastname: Valenti
authors.forename: Philippe
authors.initials: P
authors.lastname: Sauzières
authors.forename: Denis
authors.initials: D
authors.lastname: Katz
authors.forename: Ibrahim
authors.initials: I
authors.lastname: Kalouche
authors.forename: Alexandre Sahin
authors.initials: AS
authors.lastname: Kilinc
mesh_terms: D000203:Activities of Daily Living; D000368:Aged; D000369:Aged, 80 and over; D019643:Arthroplasty, Replacement / Q000009:adverse effects / Q000295:instrumentation*; D001696:Biomechanical Phenomena; D004185:Disability Evaluation; D005260:Female; D005602:France; D006801:Humans; D007595:Joint Prosthesis; D008297:Male; D008875:Middle Aged; D010147:Pain Measurement; D010149:Postoperative Pain / Q000209:etiology; D011183:Postoperative Complications / Q000000981:diagnostic imaging / Q000209:etiology / Q000503:physiopathology / Q000517:prevention & control*; D011474:Prosthesis Design; D011475:Prosthesis Failure; D011859:Radiography; D016059:Range of Motion, Articular; D020127:Recovery of Function; D012189:Retrospective Studies; D017006:Rotator Cuff / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery*; D000070636:Rotator Cuff Injuries; D012421:Rupture; D012785:Shoulder Joint / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery*; D020069:Shoulder Pain / Q000209:etiology; D013708:Tendon Injuries / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery*; D013997:Time Factors; D016896:Treatment Outcome