Femoral allograft augmentation in addition to locking plate fixation in displaced proximal humerus fractures: a retrospective case-series

Background: Proximal humerus fractures (PHFs) rank among the most prevalent fractures in adults and the elderly, with approximately 20% of them displaced and requiring surgery. Despite various operative strategies, no consensus exists on the optimal treatment for displaced PHFs. Locking plate (LCP) fixation is widely used but has high complication rates, especially in the elderly. To mitigate these risks, cortical allografts have been utilized, however, complications and challenges persist. Cancellous allografts, proven effective in other fractures, may reduce complications and improve outcomes. This study retrospectively evaluated femoral allograft augmentation with LCP fixation in displaced PHFs. Methods: This single-center retrospective case-series reviewed patients with displaced 2-, 3- or 4-part PHFs treated with femoral allograft augmentation and LCP fixation. Follow-ups were at 2 to 4 weeks, 6 weeks to 3 months, 4 to 7 months, and 10 to 14 months. Functional, radiological, and clinical outcomes were assessed by reviewing patients' records. Results: Fourteen patients were included with a mean follow-up of 9.6 ± 4.4 months (range, 1–14). At the last follow-up, mean range of motion was 138.9 ± 35.5° anteflexion, 46.7 ± 24.4° external rotation, internal rotation 50.0 ± 11.0°, and 122.8 ± 36.0° of abduction. Mean humeral head height was 17.2 ± 3.0 mm at the first follow-up and 17.3 ± 3.6 mm at the last follow-up. The mean humeral neck shaft angle was 135.7 ± 10.1° at the post-operative x-ray and 135.4 ± 11.1° at the final follow-up. Three major complications were reported: 2 infections and one avascular necrosis. Conclusion: Femoral allograft augmentation with LCP fixation for displaced PHFs demonstrated favorable clinical and radiological outcomes in this retrospective case-series. This technique may provide increased construct stability in displaced PHFs. Further prospective comparative studies are needed to confirm these findings. Level of Evidence: Level IV; Case series with no comparison group; Treatment study.