One hundred and ninety-eight consecutive patients (247 vascularized fibular grafts) were studied to determine the prevalence of morbidity at the donor site after the grafts had been obtained. Objective motor weakness, subjective discomfort in the ankle and other sites in the leg, and sensory abnormalities in the lower limb (or limbs) from which the graft had been obtained were recorded. The average duration of follow-up was forty-seven months (range, twenty-four to 144 months). Kaplan-Meier analysis was used to estimate the prevalence of each finding for the entire cohort over time.Forty-seven (19.0 per cent) of the 247 lower limbs had at least one of the findings, and eighteen (24.3 per cent) of the seventy-four limbs for which data were available at five years or more had findings at that time. Twenty-five (10.1 per cent) of the 247 limbs had evidence of motor weakness at three months postoperatively, although no limb had this finding subsequently. At five years or more postoperatively, the prevalence had decreased to two (2.7 per cent) of the seventy-four limbs. Twelve (4.9 per cent) of the 247 limbs had sensory deficits at three months; this increased to 11.8 per cent (95 per cent confidence interval, 7.7 to 17.7 per cent), according to the Kaplan-Meier analysis, at five years. Pain at sites other than the ankle was noted in nine (3.6 per cent) of the 247 limbs at three months and in 8.9 per cent (95 per cent confidence interval, 5.5 to 14.1 per cent), according to the Kaplan-Meier analysis, at five years. The prevalence of pain in the ankle also increased with time, from four (1.6 per cent) of the 247 limbs at three months to 11.5 per cent (95 per cent confidence interval, 7.4 to 17.6 per cent), according to the Kaplan-Meier analysis, at five years.Removal of a vascularized portion of the fibula is associated with a low prevalence of motor weakness and sensory deficits in the foot. The prevalence of pain in the ankle and lower limb increases with time, with some patients having a late onset of the symptoms. While free vascularized fibular grafts remain ideal for many applications, the morbidity must be weighed against the benefits.