Erse shoulder arthroplasty performed with use of 5.0-mm peripheral locking screws for baseplate fixation and a lateralized center of rotation for the treatment of a rotator cuff deficiency....

Background: Patients who have pain and dysfunction from glenohumeral arthritis associated with severe rotator cuff deficiency have few treatment options. The goal of this study was to retrospectively evaluate the short-term results of arthroplasty with use of the Reverse Shoulder Prosthesis in the management of this problem. Methods: We report the results for sixty patients (sixty shoulders) with a rotator cuff deficiency and glenohumeral arthritis who were followed for a minimum of two years. Thirty-five patients had no previous shoulder surgery, whereas twenty-three had had either an open or arthroscopic rotator cuff repair, one had had a subacromial decompression, and one had had a biceps tendon repair. All patients were assessed preoperatively and postoperatively with the American Shoulder and Elbow Surgeons scoring system for pain and function and with visual analog scales for pain and function. They were also asked to rate their satisfaction with the outcome. The shoulder range of motion was measured preoperatively and postoperatively. Results: The average age of the patients was seventy-one years. The average duration of follow-up was thirty-three months. All measures improved significantly (p < 0.0001). The mean total score on the American Shoulder and Elbow Surgeons system improved from 34.3 to 68.2; the mean function score, from 16.1 to 29.4; and the mean pain score, from 18.2 to 38.7. The score for function on the visual analog scale improved from 2.7 to 6.0, and the score for pain on the visual analog scale improved from 6.3 to 2.2. Forward flexion increased from 55.0° to 105.1°, and abduction increased from 41.4° to 101.8°. Forty-one of the sixty patients rated the outcome as good or excellent; sixteen were satisfied, and three were dissatisfied. There were a total of thirteen complications in ten patients (17%). Seven patients (12%) had eight failures, requiring revision surgery to another Reverse Shoulder Prosthesis in five patients (one shoulder had two revisions) and revision to a hemiarthroplasty in two patients because of deep infection. Conclusions: The data from this study suggest that arthroplasty with the Reverse Shoulder Prosthesis may be a viable treatment for patients with glenohumeral arthritis and a massive rotator cuff tear. However, future studies will be necessary to determine the longevity of the implant and whether it will provide continued improvement in function. Level of Evidence: Therapeutic Level IV. See Instructions to Authors for a complete description of levels of evidence.

Houlders) were managed with reverse shoulder arthroplasty for the treatment of irreparable rotator cuff dysfunction without glenohumeral arthritis. The indications for reverse shoulder arthroplasty were persistent shoulder pain and dysfunction despite a minimum of six months of nonoperative treatment, the presence of at least a two-tendon tear, and Hamada stage-1, 2, or 3 changes in a patient for whom a non-arthroplasty option did not exist. Fifty-eight patients (sixty shoulders) had a minimum of two years of follow-up. Thirty-four shoulders had had no previous surgery (Group A), and twenty-six shoulders had had at least one previous surgical procedure (Group B). Postoperatively, patients were prospectively followed both clinically and radiographically. Survival analysis was performed, with the end points being removal or revision of the implant, radiographic loosening, and declining American Shoulder and Elbow Surgeons score. Results: Common characteristics of patients managed with reverse shoulder arthroplasty in this study were pain and (1) <90° of arm elevation at the shoulder without anterosuperior escape (n = 40; 66.6%); (2) 90° of elevation (n = 4; 6.7%). The average duration of follow-up was fifty-two months (range, twenty-four to 101 months). All measured outcomes improved postoperatively. For all patients, the average American Shoulder and Elbow Surgeons score improved from 33.3 to 75.4 (p < 0.0001), the average Simple Shoulder Test score improved from 1.6 to 6.5 (p < 0.0001), the average visual analog score for pain improved from 6.3 to 1.9 (p < 0.0001), the average visual analog score for function improved from 3.2 to 7.1 (p < 0.0001), the average forward flexion improved from 53° to 134° (p < 0.0001), the average abduction improved from 49° to 125° (p < 0.0001), the average internal rotation improved from S1 to L2 (p < 0.0001), and the average external rotation improved from 27° to 51° (p = 0.001). There were a total of twelve complications in eleven patients (prevalence, 20%). The survivorship at a mean of fifty-two months (range, twenty-four to 101 months) was 90.7% for all patients, 91.8% for Group A, and 87% for Group B. Conclusions: When non-arthroplasty options either have failed or have a low likelihood of success, reverse shoulder arthroplasty provides reliable pain relief and return of shoulder function in patients with massive rotator cuff tears without arthritis at the time of short to intermediate-term follow-up. Level of Evidence: Therapeutic Level IV. See Instructions to Authors for a complete description of levels of evidence....

Background: Evaluations of functional outcomes of reverse shoulder arthroplasty have revealed variable improvements in the range of motion and high rates of scapular notching. The purpose of this study was to systematically examine the impact of surgical factors (location of the glenosphere on the glenoid and tilt angle of the glenosphere on the glenoid) and implant-related factors (implant size, center-of-rotation offset, and humeral neck-shaft angle) on impingement-free abduction motion. Methods: A computer model was developed to virtually simulate abduction/adduction motion and its dependence on five surgical and implant-related factors. Three conditions were tested for each factor, resulting in a total of 243 simulated combinations. The overall motion was determined from 0° of abduction until maximum abduction, which would be limited by impingement of the humerosocket on the scapula. In those combinations in which 0° of abduction could not be achieved, the adduction deficit was recorded. Results: The largest average increase in the range of impingement-free abduction motion resulted from a more lateral center-of-rotation offset: the average increase was 31.9° with a change in the center-of-rotation offset from 0 to 10 mm, and this change resulted in an increase in abduction motion in eighty of the eighty-one combinations. The position of the glenosphere on the glenoid was associated with the second largest average increase in abduction motion (28.1° when the glenosphere position was changed from superior to inferior, with the change resulting in an increase in seventy-one of the eighty-one combinations). These factors were followed by glenosphere tilt, humeral neck-shaft angle, and prosthetic size in terms of their effects on abduction motion. The largest effect in terms of avoiding an adduction deficit was provided by a humeral neck-shaft angle of 130° (the deficit was avoided in forty-nine of the eighty-one combinations in which this angle was used), followed by an inferior glenosphere position on the glenoid (deficit avoided in forty-one combinations), a 10-mm lateral offset of the center of rotation, inferior tilt of the glenosphere, and a 42-mm-diameter prosthetic size. Conclusions: An understanding of a hierarchy of prosthetic design and implantation factors may be important to maximize impingement-free abduction motion as well as to avoid inferior impingement. Clinical Relevance: A better understanding of these factors may lead to a reduction in inferior scapular notching and improvements in impingement-free motion after reverse shoulder replacement.

Salvage procedure for this problem....