Enovis SMR reverse shoulder arthroplasty for complex proximal humerus fractures in patients over 80 years of age

Literature focusing on reverse shoulder arthroplasty (RSA) for complex proximal humerus fractures (PHFs) in patients aged ≥ 80 years is limited. This study aimed to evaluate clinical and radiological outcomes of RSA and tuberosity fixation for complex four-part PHFs in elderly patients, with a minimum follow-up (FU) of 24 months. The secondary aim was to assess tuberosities healing rate and correlate it with clinical outcomes.

We retrospectively analyzed 26 patients (8 males, 18 females; mean age 84.6 years) who underwent cementless RSA for four-part PHFs. At the final FU, Constant-Murley score (CS), a 3-grade satisfaction scale and VAS scale were recorded. Radiological healing of greater (GT) and lesser tuberosity (LT) was also evaluated.

At a mean FU of 38 months, the mean CS was 61.30 ± 5.61 (range 38-76). Tuberosity healing occurred in 88% of patients. No significant difference (P > 0.05) in CS was found between patients with GT healing (62.80 ± 5.30) and those without (59.70 ± 1.61). Active external rotation (ER) was significantly higher in patients with GT healing (22° ± 6.28) than without (4° ± 2.18). Patients with isolated GT healing showed greater ER and internal rotation (IR) than those with combined GT-LT healing in the combined group (27° ± 7.58 vs. 16° ± 3.28, P < 0.01). Patients satisfaction was high (95%). No complications, except for one acute periprosthetic infection occurred.

RSA is a safe and effective treatment for complex four-part PHFs in patients over 80 years. The high tuberosity healing rate (88%) underlines the importance of fixation technique; however, tuberosity healing did not correlate with overall shoulder function but only with active external rotation. As for patients around 70 yrs, healing of LT was linked to GT healing, as isolated LT healing was never observed.