Prevalence of Cam and Pincer Type of Femoroacetabular Impingement on Computed Tomography in Asymptomatic Population: A Study in Tertiary Care Hospital

Abstract

Objective

The fundamental goal of was the determination of the presence of cam and pincer morphology and the alpha angle ranges in patients without any symptoms or prior femoroacetabular impingement.

Material and methods

Our retrospective cross-sectional study was performed in tertiary care hospital. Abdominal computed tomography (CT) was performed on a total of 78 persons for non-hip-related causes. Patients who had femoroacetabular impingement were disqualified for the study. Additionally, the femoral head-neck offset was measured, as well as the center-edge angle, the angle of the acetabular version, and an estimation of the acetabular crossover sign. The alpha angle measurement was superior femoral head-neck junction at the anterior aspect using AN as well as AR images.

Results                                                        

Cam (an increase of alpha angle, reduced femoral head-neck offset) and pincer type of morphology were detected in a total of 20.0%, 26.8%, 25.8%, 10.2%, and 11.7% of hips, respectively (increased center-edge angle and decreased acetabular version and presence of acetabular crossover sign). The mean AR was between 40.32° ±4.34°SD and 49.11° ±4.57°SD and AN was 41.22° ±4.66°SD. Statistically, a significant difference was assessed between the AR and AN values (P <0.001). The largest AR values were seen at the femoral head-neck intersection, at the anterosuperior aspect.

Conclusion

Alpha angles were larger in asymptomatic participants, at the femoral head-neck junction, anterosuperior aspect in comparison to axial oblique CT images in the anterosuperior area. The morphological pattern of pincer and cam-type can also be assessed using measurements that are outside the normal range for the general population.