Long-term functional outcomes of augmented primary repair using the peroneus brevis tendon for traumatic Achilles tendon ruptures: a retrospective cohort study

Achilles tendon rupture is increasingly common and may result in significant functional impairment. Intraoperative findings such as frayed tendon ends, poor tendon quality, and larger tendon gaps may compromise the reliability of primary end-to-end repair alone. The purpose of this study was to evaluate the mid- to long-term functional outcomes of primary repair with peroneus brevis augmentation in closed traumatic Achilles tendon ruptures with unfavorable intraoperative findings. This retrospective cohort study included patients with closed traumatic Achilles tendon ruptures treated with primary end-to-end repair combined with peroneus brevis tendon augmentation. Demographic data, intraoperative characteristics, surgical techniques, and complications were reviewed. Functional outcomes were assessed using the Achilles Tendon Total Rupture Score (ATRS) and the American Orthopaedic Foot and Ankle Society (AOFAS) Ankle–Hindfoot score at final follow-up. Thirty-five patients (36 Achilles tendons) were included, with a mean follow-up of 55.94 ± 32.52 months. Most ruptures demonstrated frayed tendon ends and tendon gaps greater than 2 cm. At final follow-up, functional outcomes were good to excellent, with mean ATRS and AOFAS scores of 93.28 ± 6.69 and 93.28 ± 7.69, respectively. All patients regained satisfactory ankle range of motion and plantarflexion strength, and were able to perform a single-heel rise. No tendon re-ruptures or major complications were observed. Primary end-to-end repair augmented with the peroneus brevis tendon provides reliable mid- to long-term functional outcomes for closed traumatic Achilles tendon ruptures with unfavorable intraoperative characteristics. This technique appears to be a safe and effective option to enhance repair strength and minimize the risk of re-rupture in selected patients.