Effect of tuberosity repair on functional outcome of reverse shoulder arthroplasty in proximal humerus fractures.

PURPOSE: Unsatisfactory results of hemiarthroplasty in Neer's 3- and 4-part proximal humerus fractures in elderly, have led to the shift towards reverse shoulder arthroplasty (RSA). The objective of our study was to repair the tuberosities that are generally overlooked during RSA and observe its impact on the functional outcome and shoulder scores.

METHODS: Elderly patients with acutely displaced or dislocated 3- or 4-part proximal humerus fractures from July 2013 to November 2019 were treated with RSA along with tuberosity repair by non-absorbable sutures and bone grafting harvested from the humeral head. Based on the tuberosity healing on shoulder radiographs at 9th postoperative month, the patients were divided into 2 groups, as the group with successful tuberosity repair and the other with failed tuberosity repair. Statistical analysis of the functional outcome and shoulder scores between the 2 groups were done by independent t-test for normally distributed parameters and Mann-Whitney test for the parameters, where data was not normally distributed.

RESULTS: Of 41 patients, tuberosity healing was in 28 (68.3%) and failed in 13 (31.7%) cases. Lysis of the tuberosity occurred in 5 patients, tuberosity displacement in 2, and nonunion in 2. Mean age was 70.4 years (range 65 - 79 years) and mean follow-up was 58.7 months (range 18 - 93 months). There were no major complications. Group with successful tuberosity repair showed improvement in mean active range of movements, like anterior elevation (165.1° ± 4.9° vs. 144.6° ± 9.4°, p = 0.000), lateral elevation (158.9° ± 7.2° vs. 138.4° ± 9.6°, p = 0.000), external rotation (30.5° ± 6.9° vs. 35.0° ± 6.3°, p = 0.367), internal rotation (33.7° ± 7.5° vs. 32.6° ± 6.9°, p = 0.671) and in mean shoulder scores including Constant score (70.7 ± 4.1 vs. 55.5 ± 5.7, p = 0.000), American shoulder and elbow surgeons score (90.3 ± 2.4 vs. 69.0 ± 5.7, p = 0.000), disability of arm shoulder and hand score (22.1 ± 2.3 vs. 37.6 ± 2.6, p = 0.000).

CONCLUSION: Successful repair and tuberosity healing around the RSA prosthesis is associated with statistically significant improvement in postoperative range of motion, strength and shoulder scores. Standardized repair technique and interposition of cancellous bone grafts, harvested from the humeral head can improve the rate of tuberosity healing.