title: Outcomes of reverse shoulder arthroplasty using a mini 25-mm glenoid baseplate.
abstract: OBJECTIVE
  As worldwide use of reverse shoulder arthroplasty (RSA) increases, a range of implant sizes may be required to match regional and ethnic variation in patients' height and bone size. The purpose of this study was to report the outcomes of RSA using a mini 25-mm-diameter glenoid baseplate in smaller patients with rotator cuff arthropathy.
  
  
  METHODS
  Between 2009 and 2012, 28 patients underwent RSA for cuff-tear arthropathy using a 25-mm circular glenoid baseplate (Aequlais Reversed, Tornier, Bloomington, MN, USA). Twenty-four patients were able to return for comprehensive follow-up. The mean height of the entire cohort was 158 ± 10 cm (5 ft. 2 in.). The indication to use a smaller baseplate was a combination of preoperative templating using computed tomography (CT) and intraoperative measurements of glenoid width.
  
  
  RESULTS
  At a mean of 36 ± 8 months' follow-up, there were no revisions or glenoid-sided failures. The mean American Shoulder and Elbow Surgeons (ASES) score was 70 ± 10, the Simple Shoulder Test (SST) was 10 ± 2, the Constant was 60 ± 10 and the Disabilities of the Arm, Shoulder and Hand (DASH) was 18 ± 15. Mean active forward elevation was 140 ± 15°, active external rotation was 21 ± 15° and active internal rotation was to the sacroiliac joint. Mean shoulder strength in flexion was 5.2 ± 1.7 kg, in external rotation was 2.9 ± 1.4 kg and in internal rotation was 4.3 ± 1.2 kg. Radiographs demonstrated no evidence of glenoid loosening. There was, however, a 62 % rate of scapular notching.
  
  
  CONCLUSIONS
  Short-term outcomes of mini 25-mm baseplate RSA in proportionally smaller patients are good and demonstrate implant safety and effectiveness. Scapular notching rates are worrisome, and additional follow-up is necessary to determine if notching is progressive and becomes symptomatic.
authors.affiliation: Roth|McFarlane Hand and Upper Limb Center, St Joseph's Health Care, University of Western Ontario, London, ON, Canada. gathwal@uwo.ca.|Roth|McFarlane Hand and Upper Limb Centre, St. Joseph's Health Care, 268 Grosvenor St, London, ON, N6A 4L6, Canada. gathwal@uwo.ca.
authors.forename: George S
authors.initials: GS
authors.lastname: Athwal
authors.affiliation: Roth|McFarlane Hand and Upper Limb Center, St Joseph's Health Care, University of Western Ontario, London, ON, Canada.
authors.forename: Kenneth J
authors.initials: KJ
authors.lastname: Faber
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D019643:Arthroplasty, Replacement / Q000379:methods*; D001860:Bone Plates / Q000009:adverse effects*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007592:Joint Diseases / Q000601:surgery; D008297:Male; D016059:Range of Motion, Articular; D012399:Rotation; D017006:Rotator Cuff / Q000473:pathology* / Q000601:surgery; D012421:Rupture / Q000601:surgery; D012540:Scapula / Q000000981:diagnostic imaging; D012785:Shoulder Joint / Q000601:surgery*; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome
keywords: BIO-RSA; Cuff-tear arthropathy; Implants; Reverse-shoulder arthroplasty; Small stature