Treatment of cephalotuberosity fractures in elderly patients treated by reverse shoulder prosthesis: a study of functional results in relation to deltoid tension.

INTRODUCTION: The treatment of proximal humerus fractures is a therapeutic challenge in the elderly as the functional demands of these patients are high. We postulated that there may be a relationship between functional results and deltoid tension when these fractures are treated with a reverse prosthesis. This study was performed to determine the optimal tension of the deltoid. The primary outcome was the constant score in relation to humeral length at the final follow-up.

MATERIALS AND METHODS: Our retrospective cohort consisted of 45 patients treated with a reverse fracture prosthesis during the period from January 2010 to July 2017. The fractures were all classified as Neer III or IV, 91% of our patients were women and the average age was 82 years.

RESULTS: Constant score and antepulsion were improved with humeral elongation between 10 and 25 mm (p < 0.02 and p < 0.05, respectively). External rotation was improved with humeral elongation (p < 0.03).

CONCLUSION: Tuberosity reinsertion improves mobility in patients treated surgically for a reverse fracture prosthesis. The recovery of anatomical retroversion seems of fundamental importance, and we confirmed that deltoid tension that must also be taken into account to improve functional results of reverse shoulder prosthesis on fracture. The ideal humeral elongation seems to be between 10 and 25 mm, in relation to the contralateral side, to obtain better functional results.