Summary

In our study population of patients with FAI, the degree of tibial torsion was not related to hip pathology. Femoral anteversion was associated with DDH and femoral retroversion with cam-type FAI.

Abstract

Background

Tibial torsion and femoral version are two factors that impact lower extremity alignment and dynamic movement of the hip. The relationship between tibial torsion, femoral version and hip pathology has not been previously extensively studied.

Objective

In a patient population with unilateral and bilateral symptomatic femoroacetabular impingement (FAI), we sought to analyze the relationship between known markers of hip pathology such as alpha angle, femoral version and lateral center edge angle (LCEA) to tibial torsion and femoral version measurements of the ipsilateral and contralateral limb. We hypothesized that there would be a significant relationship between tibial torsion, femoral version and hip pathology.

Methods

We performed a retrospective review of patients who presented to the senior author’s clinic for evaluation of hip pain. CT measurements with axial cuts of bilateral hips, knees and ankles were obtained on 200 hips (192 patients.) Tibial Torsion and Femoral Anteversion measurements for both the injured and uninjured hip were calculated by the first author. All other measurements were calculated using an imaging software. Pearson correlation coefficients and paired t-tests were used for analysis.

Results

Femoral version was 5.2 degrees more retroverted for individuals with cam-type FAI (p = 0.0003) and 4.3 degrees more anteverted for individuals with developmental dysplasia of the hip (DDH, as defined by an LCEA <25o) (p = 0.0357.) Tibial torsion was not significantly different for individuals with cam-type FAI (p =.6561) or DDH (p =.2842.) There was a 0.58043 correlation between tibial torsion of the injured leg and tibial torsion of the contralateral leg (p = 0.00001.)

Conclusions

In our study population of patients with FAI, the degree of tibial torsion was not related to hip pathology. Femoral anteversion was associated with DDH and femoral retroversion with cam-type FAI. There is a significant positive correlation between tibial torsion of the injured and contralateral leg.