Related Experiment Video
Updated: May 28, 2026
In Vivo Quantification of Hip Arthrokinematics during Dynamic Weight-bearing Activities using Dual Fluoroscopy
Published on: July 2, 2021
Femoroacetabular impingement and risk factors: a study of 50 cases
Rajesh Kumar1, Aditya Aggarwal
1Department of Orthopaedics, Postgraduate Institute of Medical Research and Education, Chandigarh, India. raji7dr7@gmail.com
Objective:
To study the asphericity of the femoral head in femoroacetabular impingement using the radiological indices alpha angle and triangular index, and correlation with risk factors.
Methods:
The study was conducted retrospectively from January 2008 to June 2010 on 50 consecutive patients with suspected cam type femoroacetabular impingement of the hip who reported to the orthopaedics outpatients department of the Postgraduate Institute of Medical Education and Research. Ten controls were also used in the study. Radiographs of the affected hip were taken and then the alpha angle and triangular index were measured and correlated with various risk factors.
Results:
In the anteroposterior view the alpha angle range was from 55° to 106° for the cases and from 54° to 70° for the controls. In the lateral view the range was from 62° to 104° for the cases and from 54° to 62° for the controls. The mean alpha angle in the anteroposterior view was measured as 75°± 10° in the cases and 61°± 6° in the controls, and the mean in the lateral view was 74°± 8° in the cases and 58°± 6° for the controls. The triangular index range in the radiographs was from 1 to 7 in the cases and from 0 to 1 for the controls. The mean triangular index in the radiographs was 2.9 ± 1.2 for the cases and 0.2 ± 0.4 for the controls.
Conclusion:
There was no significant correlation between the age and gender of the patient and the femoroacetabular impingement. However, there was significant correlation between the body mass index of the patient and the femoroacetabular impingement.
