Return to Sports Activities After Flexor Hallucis Longus Transfer for Neglected Achilles Tendon Rupture

Transfer of the flexor hallucis longus (FHL) is known to be effective in the treatment of neglected Achilles tendon rupture (ATR). However, evidence on the return to sports activity levels and clinical outcomes is not sufficient. The aim of this study was assessing clinical outcomes and level of sports activity after FHL tendon transfer for treatment of neglected ATR. Twenty-eight patients who underwent FHL transfer for neglected ATR were analyzed retrospectively. Sports activity status was assessed using the Tegner Activity Scale (TAS). Clinical outcomes were evaluated using the Achilles tendon total rupture score and the American Orthopedic Foot and Ankle Society Ankle-Hindfoot Scale. By the post hoc power analyses, the power level of more than 80% was identified. The preinjury median TAS score was 4 point and unchanged at the last follow-up. The mean Achilles tendon Total Rupture Scores and American Orthopedic Foot and Ankle Society Ankle-Hindfoot Scale scores at the last follow-up were 81 and 93, respectively. While the median TAS was unchanged, 9/28 patients suffered from lower activity level after the procedure. In conclusion, midterm results of FHL transfer for neglected ATR were shown to be favorable. The median TAS score was maintained. Nonetheless, 32% of patients returned to sports activities with a TAS score 1 point lower than that at preinjury and with less favorable clinical outcomes.