From Ankle to Knee: Donor-Site Morbidity after Peroneus Longus Tendon Graft for ACL Reconstruction Assessed by the Kitaoka Ankle-Hindfoot Score - A Prospective Cohort Study.

INTRODUCTION: Peroneus longus tendon (PLT) autograft is increasingly used for anterior cruciate ligament (ACL) reconstruction, but concerns persist regarding donor ankle morbidity and potential compromise of lateral ankle stability. This study prospectively evaluated donor-site morbidity after PLT harvest using the Kitaoka Ankle-Hindfoot Scale over a 6-month follow-up period. MATERIALS AND METHODS: This prospective observational cohort study included 45 patients with isolated ACL tears who underwent arthroscopic single bundle ACL reconstruction using autologous full thickness PLT grafts. All patients were operated at a single tertiary-care center. The Kitaoka Ankle-Hindfoot Scale was recorded preoperatively and postoperatively at 14 days, 4 weeks, 12 weeks, and 6 months. Only patients without pre existing ankle or foot pathology were included. Donor ankle pain, function, alignment, and total scores were analyzed using paired t-tests and repeated--measures analysis of variance. RESULTS: The cohort had a mean age of 29.95 years, and the mean interval between injury and surgery was 4.4 months. All patients had normal pre-operative donor ankle function with a mean Kitaoka score of 100. At 14 days, the mean score decreased to 71.42 ± 6.92, indicating transient functional impairment. Scores improved to 92.95 ± 5.19 at 30 days, 97.86 ± 4.63 at 90 days, and 99.11 ± 3.81 at 180 days. The change in total score between pre-operative and 6-month follow-up (100.0 ± 0.0 vs. 99.11 ± 3.81) was not statistically significant (P = 0.064). Component analysis showed no significant deterioration in pain (40 vs. 38.88 ± 3.17; P = 0.160), function (50 vs. 49.74 ± 0.63; P = 0.065), or alignment (10 vs. 10; no change). Between 14 days/30 days and 6 months, the increase in total scores was highly significant (P < 0.0001). At final follow-up, 42 patients (93.3%) had excellent and 3 (6.7%) had good donor ankle function. No cases of ankle instability, gait abnormality, or major functional compromise were observed. CONCLUSION: Harvesting the PLT for ACL reconstruction results in minimal and reversible donor-site morbidity, with donor ankle function returning to near normal levels by 6 months. PLT autograft is a safe and mechanically reliable graft choice with preservation of ankle biomechanics as reflected by sustained Kitaoka Ankle-Hindfoot scores.