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Updated: Aug 6, 2026
Vascularized Composite Upper Limb Allograft Harvesting for Proximal Arm Allotransplantation
Published on: June 13, 2025
Influence of allograft augmentation on surgical outcomes and complications in proximal humerus fractures: a
Christiane Barthel1,2, Franziska Rudolph3, Yannik Kalbas4
1Department of Shoulder and Elbow Surgery, Schulthess Klinik, Lengghalde 2, Zurich, CH-8008 , Switzerland. christiane.barthel@kws.ch.
Background:
Proximal humerus fractures predominantly affect elderly patients and pose a growing clinical burden. This study evaluates the impact of allograft augmentation on operative time, fracture reduction quality, and complication rates compared with standard fixation across different fracture morphologies.
Methods:
This retrospective matched-pair study included patients surgically treated for proximal humerus fractures with locking plate fixation at a single tertiary trauma center between 01.01.2014 and 31.12.2024. Patients treated with allograft augmentation (Group A) were matched 1:1 to patients without allograft (Group NA) using exact matching for Mayo FJD fracture morphology and sex, and propensity score matching for age. Radiological outcomes were assessed using pre- and postoperative neck-shaft angles, with normalization defined as correction into the physiological range (120°-150°). Complications and operative parameters were recorded. Paired statistical analyses were applied.
Results:
A total of 1,012 patients were treated during the study period; after selection and matching, 102 matched patient pairs (204 patients) were analyzed. Operative time was longer with allograft augmentation (141.3 ± 40.3 vs. 126.9 ± 50.0 min; p = 0.08), reaching statistical significance only in varus posteromedial fractures (144.4 ± 37.8 vs. 122.2 ± 39.6 min; p = 0.007). Although overall postoperative alignment rates were comparable, allograft augmentation more frequently achieved correction to a physiological neck-shaft angle (62.7% vs. 48.0%; p = 0.044). Overall complication rates were comparable (20.6% vs. 26.5%; p = 0.43), while functional complications occurred less frequently with allograft augmentation (1.0% vs. 7.8%; p = 0.035).
Conclusions:
Allograft augmentation was associated with a higher rate of restoration to a physiological neck-shaft angle without an increase in overall complication rates, although at the cost of slightly longer operative time in selected fracture patterns. The clinical relevance of these radiographic findings requires further evaluation using validated patient-reported outcome measures. While secondary analyses were exploratory, the findings suggest that allograft augmentation may be useful in situations where achieving and maintaining anatomical alignment is challenging.
Level Of Evidence:
III, retrospective comparative study.
