Free vascularised fibular flap harvesting in children: An analysis of donor-site morbidity.

Background: The free vascularised fibular flap (FVFF) is widely used to treat bone defects, although it must be harvested from a healthy site. The objective of this study was to assess clinical morbidity and radiological changes at the FVFF donor site in children.

Hypothesis: Distal fibular stabilisation using a tibial strut decreases the prevalence of valgus ankle deformity.

Material And Method: Thirty-one children managed at two centres between 1994 and 2014 were included. Mean age was 8.9 years (range, 2-14 years) and mean follow-up was 6.6 years (range, 2-21 years). Early and delayed complications were evaluated.

Results: Of the 17 early complications, 82.4% resolved fully within 7 months. Valgus ankle deformity developed in 6 (19.4%) patients. Age-residual fibula index under 16 was not significantly associated with valgus ankle deformity, although the P-value was borderline (P<0.058). Residual distal fibula length did not predict valgus ankle deformity. Three techniques were used for fibular reconstruction: syndesmotic screw, tibial strut, and both. None of these techniques prevented the occurrence of valgus ankle deformity.

Discussion: Clinical donor-site morbidity after FVFF harvesting, although noticeable, usually resolved promptly. Taken alone, an age-residual fibula index under 16 did not predict valgus ankle deformity. We recommend a distal tibio-fibular quadricortical syndesmotic screw or combined syndesmotic screw-tibial strut fixation to prevent valgus ankle deformity, which is common when a tibial strut is used alone.

Level Of Evidence: IV.