Vascularized Fibular Grafting in Treatment of Femoral Neck Nonunion: A Prognostic Study Based on Long-Term Outcomes.

BACKGROUND

The purpose of this study was to evaluate the long-term efficacy and prognostic factors predicting success of revision surgery with free vascularized fibular grafting (FVFG) for treatment of femoral neck nonunion.

METHODS

We prospectively enrolled patients who underwent revision surgery with FVFG between January 2001 and January 2013 in a tertiary hospital in China. A total of 98 patients with a minimum 5-year follow-up were included for analysis. The criteria for FVFG failure were conversion to hip arthroplasty, recommendation for a hip arthroplasty, or a Harris hip score of <80 points. Demographic information, the preoperative neck shortening ratio (NSR), the fixation method, and postoperative radiographic parameters including the postoperative NSR and neck-shaft angle (NSA) were recorded for prognostic analysis.

RESULTS

At an average of 9.8 ± 3.5 years (range, 3 to 17 years) postoperatively, the overall success rate of this surgical procedure was 77% (75 of 98). The success and failure groups had no significant differences in age, fixation method, interval between initial fixation and revision surgery, or postoperative NSA. The success group had a significantly higher NSR than the failure group both preoperatively (77.8% versus 62.4%, p < 0.001) and postoperatively (87.6% versus 78.4%, p = 0.001). The receiver operating characteristic (ROC) curve analysis revealed an optimal cutoff for preoperative NSR of 60% to predict the outcome. Patients with a preoperative NSR of >60% had a success rate of 91% (68 of 75).

CONCLUSIONS

Revision surgery with FVFG and internal fixation is an effective and important option for treating nonunion of the femoral neck in young patients without severe preoperative shortening and neck resorption (preoperative NSR of >60%).

LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.