Comparison Between Computed Tomography Arthrography (CTA) Without Traction, CTA With Traction, and Magnetic Resonance Arthrography in Hip Impingement: What Is the Best Method?

Purpose: Femoro-acetabular impingement (FAI) is a possible mechanism for the development of early osteoarthritis. FAI occurs when there is a conflict between the rim of the acetabulum and the femoral neck, usually due to irregularities of the proximal femur or acetabulum. Our aims were to compare the diagnostic efficacy of computed tomography arthrography (CTA) without traction, CTA with traction, and magnetic resonance arthrography (MRA) for the detection and grading of chondral and labral lesions in patients with a clinically positive impingement test and to determine the correlation between imaging findings and arthroscopic data in patients who had undergone surgery.

Patients And Methods: This monocentric, observational, retrospective study was conducted on 95 consecutive patients referred to our imaging department with clinical symptoms suggestive of FAI between January 2012 and May 2023. A total of 21 patients underwent therapeutic arthroscopy after the failure of medical treatment. These patients underwent either CTA without traction, CTA with traction, or MRA. Chondral and labral lesions were assessed by two musculoskeletal radiologists who were unaware of the original arthroscopy findings and interpretations. The modified MAHORN (Multicenter Arthroscopy of the Hip Outcomes Research Network) classification was used for grading during imaging and surgery.

Results: There was no significant difference between the examination techniques for the diagnosis of labral lesions (p=0.1737). Cartilage lesions preferentially affected the acetabular side compared to the femoral side, with no significant difference between the examination techniques for the diagnosis of chondral lesions (p=0.1429 for femoral cartilage, p=0.0944 for acetabular cartilage). No significant difference was found between the imaging and surgical data for the diagnosis of labral and cartilage lesions, even when the three imaging techniques were combined (labrum, p=0.1797; acetabular cartilage, p=0.0588; femoral cartilage, p=0.6547).

Conclusion: No significant difference was found between CTA without traction, CTA with traction, and MRA procedures for the detection and grading of chondral and labral lesions. Furthermore, there was no significant difference between the imaging and surgical data when the three imaging techniques were combined.