RESULTS OF REVERSE SHOULDER ARTHROPLASTY IN PROXIMAL HUMERUS FRACTURE SEQUELAE

Abstract

The purpose was to evaluate the results of reverse shoulder arthroplasty (RSA) in proximal humerus fracture sequelae (FS).

Multicenter retrospective series of forty-five consecutive patients operated between 1995 and 2003. Types of FS included: cephalic collapse and necrosis (n=8), chronic locked dislocation (n=5), surgical neck nonunion (n=7), severe malunion (twenty), and isolated greater tuberosity malunion (n=3). Twenty-six patients had surgical treatment of the initial fracture and seventeen had non-surgical treatment; thirty-three Delta and ten Aequalis reverse prosthesis were implanted. Mean age at surgery was seventy-three years (range, fifty-seven to eighty-six). Forty-three patients were available for clinical and radiologic evaluation with a mean follow-up of thirty-nine months (range, twenty-four to ninety-five).

Nine re-operations (21%) and ten complications (23%) were encountered, including four infections (leading to two resection-arthroplasties), two instabilities, one glenoid fracture (converted to hemiarthroplasty) and one axillary nerve palsy. Thirty-six patients (83%) were satisfied or very satisfied with their result. The adjusted Constant score improved from 29% preoperatively to 75% postoperatively (p< 0.0001), the Constant score for pain from fou to twelve points (p< 0.0001), and active anterior elevation from 59° to 114° (p< 0.0001). Active rotations were limited. A positive postoperative hornblower test negatively influenced Constant score (forty-two points compared to 61.5 points, p=0.004) and external rotation (−6° compared to 15°, p=0.004). The lowest functional results were observed in surgical neck nonunions (with five complications) and isolated greater tuberosity malunions. In type four fracture sequelae, patients who had an osteotomy or resection of the GT (n=9) had better forward flexion (140° compared to 110°, p=0.026) and better Constant score (sixty-three points compared to forty-six points, p=0.07).

RSA can be a surgical option in elderly patients with FS, specifically for those with severe malunion (type four fracture sequelae) where hemiarthroplasty gives poor results. By contrast, surgical neck nonunions (type three) and isolated greater tuberosity malunions are at risk for low functional results. The surgical technique and the remaining cuff muscles (teres minor) are important prognostic factors. Functional results are lower and complications/reoperations rates are higher than those reported for RSA in cuff tear arthritis.