Risk Factor Study Of Femoral Head Collaspse After Free Vascularized Fibular Graft The Treatment Of Avascular Necrosis Of Femoral Head

OBJECTIVE: To evaluate the risk factors and duration of femoral head collapse after free vascularized fibular graft(FVFG)for the treatment of avascular necrosis of femoral head(AVN).METHODS: Data of patients underwent FVFG for the treatment of AVN between January 2006 and December 2012 at our department was studied retrospectively.Ages,genders,causes of AVN,sides of AVN,stages of AVN and presence of femoral head collapse were recorded.RESULTS: 215 cases(307 hips)with a mean follow-up duration of 51.3 months(from 3 months to 114 months)were included in the study.Femoral heads of 260 hips(84.69%)did not collapse at the last follow-up,and femoral head collapses were observed in the remaining 47 hips(15.31%).Femoral head collapses were observed between 3 months and 24 months after operation,and the first,second,and third quartile of the time point of femoral head collapses were 3 months after operation,6 months after operation,and 15 months after operation,respectively.CONCLUSIONS: The risk factors evaluation demonstrated that age 40 years old,alcohol induced AVN and Ficat-Arlet III stage AVN were the risk factors of femoral head collapse after FVFG for AVN.FVFG could provide excellent outcomes for the treatment of AVN.The risk duration of femoral head collapse after FVFG for AVN is in 15 months after operation,and the risk factors are age 40 years old,alcohol induced AVN and Ficat-Arlet III stage AVN.For the patients with risk factors,the follow-up duration should be shorten,and the rehabilitation intensity should be reduced.