The purpose of this study was to clarify and document light-touch sensory change of the lower leg after arthroscopically-assisted ACL reconstruction using medial hamstring tendons with a vertical incision. Eighty-six patients were directly followed up during a mean of 32.0 months after surgery. Sixty patients responded to a mailed questionnaire about affect of sensory change on daily living. Forty-seven patients out of 86 (55%) indicated some sensory change of the lower leg, which was usually hypoesthesia with an average verbal score of 6.9. The questionnaire revealed that one patient out of 60 complained that the sensory change adversely affected daily living. A sensory-change area with a mean of 53.2 cm(2) was located distally from the incision in 40% of the cases; it was located proximally and distally in 56%. Blunt exposure for harvesting the tendons failed to decrease the occurrence of the sensory change. After ACL reconstruction using medial hamstring tendons with a vertical incision, sensory change was frequently found. Daily living was, however, only slightly affected by the sensory change.