RT Journal A1 Duquin, Thomas R. A1 Jacobson, Justin A. A1 Sanchez-Sotelo, Joaquin A1 Sperling, John W. A1 Cofield, Robert H. T1 Unconstrained Shoulder Arthroplasty for Treatment of Proximal Humeral Nonunions JF The Journal of Bone & Joint Surgery JO The Journal of Bone & Joint Surgery YR 2012 FD September 5 VO 94 IS 17 SP 1610 OP 1617 DO 10.2106/JBJS.J.01975 UL http://dx.doi.org/10.2106/JBJS.J.01975 AB Background:  Unconstrained shoulder arthroplasty is one of several methods for treatment of proximal humeral fracture nonunions. The goal of this study was to define the results and complications of this procedure.Methods:  From 1976 to 2007, sixty-seven patients underwent unconstrained shoulder arthroplasty for proximal humeral nonunion and were followed for more than two years. There were forty-nine women and eighteen men with a mean age of sixty-four years and a mean duration of follow-up of nine years (range, two to thirty years). The fracture type according to the Neer classification was two-part in thirty-six patients, three-part in sixteen, and four-part in fifteen. Hemiarthroplasty was performed in fifty-four patients and total shoulder arthroplasty was done in the remaining thirteen.Results:  There were thirty-three excellent or satisfactory results according to the modified Neer rating. Tuberosity healing about the prosthesis occurred in thirty-five shoulders. The mean pain score improved from 8.3 preoperatively to 4.1 at the time of follow-up (p < 0.001). The average active shoulder elevation and external rotation improved from 46° and 26° to 104° and 50° (p < 0.001). Shoulders with anatomic or nearly anatomic healing of the tuberosities had greater active elevation at the time of final follow-up (p = 0.02). There were fourteen complications in twelve patients, with twelve reoperations including five revisions. Kaplan-Meier survivorship with revision as the end point was 97% (95% confidence interval [CI]: 94.3, 100) at one year and 93% (95% CI: 88.0, 99.2) at five, ten, and twenty years.Conclusions:  Shoulder arthroplasty decreases pain and improves function in patients with a proximal humeral nonunion. However, the overall results are satisfactory in less than half of the patients. Tuberosity healing is inconsistent and influences the functional outcome.Level of Evidence:  Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.