Femoral Cortical Indices (cti & ccr) Used for Predicting Stability of a Trochanteric Fracture after Intramedullary Nail Fixation

Background: In this study, we examined a bone quality index - which can be measured on a regular hip x-ray - as a mean of predicting value for the stability of pertrochanteric fractures treated surgically with proximal femoral nail (PFN). We used the relative values for bone quality (CTI and CCR) as predictors for fracture stability after treatment, and the possibility of periprosthetic fracture failure.

Methods: Complete medical record including x-rays where collected for patients hospitalized as a result of pertrochanterric fractures. Calculations of the CCR and CTI values where made after measurement of the EWLT (Endosteal Width at level of Lesser Trochanter), the EW10 and CW10 (Endosteal Width and Cortical Width 10cm from the lesser trochanter, respectively) where made. Of the 100 patients who met the inclusion criteria for the study, 11 failed to achieve a stable fixation.

Results: EWLT was found to be consistent with success, and the possibility of a fracture fixation failure. It was found that a relatively small width of the canal at the lesser trochanter was consistent with higher chances of success. The EWLT variable was found to be significant in this model as a protective effect from failures [95% CI 0.4-0.8, P <0.5]

Conclusion: A large EWLT is associated with a fracture fixation failure when treated surgically with proximal femoral nail (PFN). We recommend for those patients to consider this risk and hence to adapt the treatment strategies accordingly.

*CTI - cortical thickness index

*CCR – calcar to canal ratio