Great tuberosity fixation does not affect healing and clinical outcomes in RSA performed in proximal humeral fractures in elderly patients.

Purpose: Aims of our study were to define whether the great tuberosity (GT) positioning fixation in reverse shoulder arthroplasty (RSA) after proximal humeral fracture (PHF) could predict tuberosity healing and its impact on clinical outcomes.

Methods: We enrolled 59 patients treated with cementless reverse shoulder arthroplasty after PHF in our institute between 2012 and 2018. The mean follow-up was 57 months (± 23.4). We divided patients into two groups according to GT positioning after fixation: Group 1 GT in contact and Group 2 GT detached at least 1 mm from humeral diaphysis. Clinical and radiographic evaluations were conducted at last follow-up.

Results: Overall GT healing rate was 64.4%, (Group 1 70.7%-Group 2 50%). A statistically significant difference (P = 0.047) was found in cortical thickness narrowing at one-third of stem length. We found a correlation between lateral cortical narrowing and GT fixation in non-anatomical position, but we observed no statistically significant differences about GT healing according to GT anatomical or non-anatomical fixation. No differences were found in shoulder function in patients whose tuberosity was healed or failed to heal.

Conclusion: GT reduction is not a predictive factor for GT healing; external stress shielding, instead, seems to be decreased in patients with postoperative anatomically reduced GT. In our study, GT healing did not affect clinical outcomes or patient's satisfaction in elderly low-demanding patients.