title: Humeral Tray-Taper Failure in Modular Reverse Total Shoulder Arthroplasty.
abstract: BACKGROUND
  Reverse total shoulder arthroplasty (RTSA) provides reconstructive options in patients previously not candidates for total shoulder arthroplasty (TSA) or who have failed previous anatomic TSA. Revision from anatomic TSA to RTSA previously required removal of all components, a difficult and extensive procedure. Modular humeral components permit conversion from anatomic TSA to RTSA without removal of well-fixed humeral components.
  
  
  OBJECTIVE
  Our purpose is to present a case series of patients treated for the unique and not previously reported complication of humeral tray-taper failure following modular RTSA. Challenges in diagnosis and treatment are described, including the use of dynamic fluoroscopy and manufacturer-specific instruments for component revision.
  
  
  METHODS
  Five patients with a total of six humeral tray-taper failures were identified from 300 patients with first-generation (titanium) humeral trays over a 7-year period. Dynamic fluoroscopic evaluation aided in diagnosis in a majority of the cases. All cases have been revised to second-generation (cobalt chrome) humeral trays.
  
  
  RESULTS
  Average follow-up was 22 ± 23 months (range 3-60 months). One individual required a second revision for the same complication, but otherwise, no additional procedures were required. Symptom relief was obtained in all patients.
  
  
  CONCLUSIONS
  This case series illustrates a previously unpublished complication of humeral tray-taper junction failure following modular RTSA. Clinical and radiographic diagnosis is challenging; however, dynamic fluoroscopic evaluation permits identification of the component failure, and revision surgery results in good outcomes. We must, however, continue to evaluate what activities are recommend for patients following shoulder arthroplasty, specifically reverse total shoulder arthroplasty.
authors: Department of Sports Medicine and Shoulder Surgery, Hospital for Special Surgery, 535 East 70th Street, New York, NY 10021 USA.
authors: Lucas S
authors: LS
authors: McDonald
authors: Department of Sports Medicine and Shoulder Surgery, Hospital for Special Surgery, 535 East 70th Street, New York, NY 10021 USA.
authors: Joshua S
authors: JS
authors: Dines
authors: Department of Sports Medicine and Shoulder Surgery, Hospital for Special Surgery, 535 East 70th Street, New York, NY 10021 USA.
authors: Christopher
authors: C
authors: Chin
authors: Department of Sports Medicine and Shoulder Surgery, Hospital for Special Surgery, 535 East 70th Street, New York, NY 10021 USA.
authors: Russell F
authors: RF
authors: Warren
authors: Department of Sports Medicine and Shoulder Surgery, Hospital for Special Surgery, 535 East 70th Street, New York, NY 10021 USA.
authors: David M
authors: DM
authors: Dines
keywords: complication; humeral tray-taper failure; modular components; reverse total shoulder arthroplasty; revision surgery