Donor site changes in early months following nonvascularized fibular harvest in children: a prospective radiological analysis.

Abstract

The exact timing of non regeneration and ankle valgus in post fibular harvest donor limbs remain elusive. The study examined the serial radiographs post harvest to better understand the transitions occurring in the ankle and leg region. We specifically focused on the noncontinuity of fibular regenerate, lateral distal tibial angle (LDTA), fibular length (fibular/tibial ratio, F/T ratio) and fibular station in the donor leg. Completeness of longitudinal fibular regeneration was documented at 6 months and accordingly two groups, with (R+) and without complete longitudinal regeneration (R-), were available for comparisons. There were 25 fibular harvests in 19 patients. The longitudinal regenerate was complete in 14 limbs (56%) (R+ group) at 6 months. The average LDTA at 6 months did not differ significantly from preoperative values. The F/T ratio decreased immediately postoperative and the trend remained sustained till 6 months. Malhotra grade corresponded inversely to F/T ratio. There was insignificant intra or intergroup affection of LDTA in R+ and R- groups over initial 6 months. The F/T ratio in R+ group recorded a downward trend till 3 months but remained static thereafter. Malhotra grades comparisons between R+ and R- revealed significant differences only at 6 months. Fibular length (F/T ratio) was found to be the critical indicator of regeneration. For the nonregenerates, ratios deteriorated significantly by 3 months. Malhotra station corresponded to changes in fibular length, although it was less quantitative. The secondary changes in lower tibia may not manifest till 6 months.