Primary unconstrained shoulder arthroplasty in patients with a fixed anterior glenohumeral dislocation

Abstract

Background: Reports of shoulder arthroplasty for the treatment of fixed glenohumeral dislocation are rare. The purpose of this study was to analyze the results following shoulder arthroplasty in patients with a fixed anterior shoulder dislocation.

Methods: Eleven patients were evaluated at a minimum of twenty-four months after they underwent an arthroplasty for the treatment of a fixed anterior shoulder dislocation. Four patients underwent a total shoulder arthroplasty, and the remainder were treated with a hemiarthroplasty. Four shoulders had osseous reconstruction of the anterior aspect of the glenoid. The patients were evaluated with use of the Constant score, measurement of active anterior elevation and external rotation, the patient's subjective grading of the result, and a radiographic examination.

Results: The mean Constant score improved from 21.1 points preoperatively to 46.0 points following the arthroplasty, and the mean active anterior elevation improved from 48.6 degrees to 90.0 degrees . The pain component of the Constant score was the most reliably improved parameter, increasing from a mean of 4.8 points preoperatively to a mean of 11.0 points postoperatively. Eight patients reported that the result was excellent or good, and the remaining three considered it to be fair. We observed seven complications in five patients, including four cases of anterior instability of the shoulder. Two of the four patients treated with a total shoulder replacement were seen to have definite loosening of the glenoid component on follow-up radiographs.

Conclusions: Shoulder arthroplasty in patients with a fixed anterior shoulder dislocation is fraught with difficulties and complications. Although arthroplasty reliably relieved shoulder pain in this population, limited functional results should be expected.