Rehabilitation progress following reverse total shoulder replacement or internal fixation for geriatric three and four-part proximal humerus fractures – A propensity score matched comparison

Background: Proximal humerus fracture is one of the most common fractures in the elderly population. However, in patients with complex fracture patterns, there is still no general consensus in the best treatment method. This study aims to evaluate the outcomes between those treated with reverse total shoulder arthroplasty (rTSA) and internal fixation (IF). Methods All geriatric patients with proximal humerus fractures undergoing surgical treatment were analysed. There were 25 patients treated with rTSA and 175 with IF. All patients followed a protocol-driven rehabilitation programme with outcome assessment at 3, 6, 12 and 24 months. Constant score, qDASH, range of motion, rate of complications and revision surgery were recorded and compared. Propensity score matching was used to select 25 matching patients from the IF group according to age and gender. Results 25 rTSA were age and gender matched with 25 IF patients. At a mean follow up of 3, 6, 12 and 24 months respectively, average constant shoulder score was 37.7/55.2/68.1/72.8 for rTSA and 45.5/60.0/64.6/70.8 for IF. Mean qDASH scores were 50.6/18.2/11.0/4.50 for rTSA and 29.4/18.5/18.4/11.0 for IF. Mean forward flexion range was 72.9/104/136/143 for rTSA and 94.4/108/109/109 for IF. Mean shoulder abduction range was 64.0/105/125/135 for rTSA and 88.6/106/108/110 for IF. There were more complications observed for IF (3) than rTSA (1) (p = 0.297) and more re-operations for IF (3) than rTSA (1) (p = 0.297). Conclusion rTSA appears to yield a slower recovery before 6 months but a better outcome at 2 years. It may be the preferred treatment for geriatric three- and four-part proximal humerus fracture, for those aiming for a better long-term functional outcome.