Role of Imaging in Femoroacetabular Impingement Syndrome: From Pathomechanics to Patient-Specific Management

Femoroacetabular impingement syndrome is a significant morphology-driven hip disorder in which abnormal osseous geometry and dynamic hip motion lead to intra- and/or extra-articular mechanical conflict. Repetitive impingement induces chondrolabral injuries, promoting early joint degeneration and representing a major pathway to osteoarthritis. Although cam and pincer morphologies and femoral torsion abnormalities are commonly observed on imaging, these features alone are not sufficient for diagnosis, requiring integration with clinical evaluation.

Imaging plays a pivotal role in assessing femoroacetabular impingement syndrome, from diagnosis to preoperative planning and postoperative follow-up. Conventional radiography remains indispensable for the primary assessment of hip morphology. Computed tomography provides high-resolution three-dimensional characterization of osseous structures and torsional alignment. Magnetic resonance imaging, including direct magnetic resonance arthrography and traction or position-specific protocols, allows detailed evaluation of chondrolabral lesions, cartilage integrity, and periarticular soft tissues. Quantitative cartilage imaging and three-dimensional modeling further enhance detection of early degeneration, motion-dependent impingement, and dynamic instability.

Accurate differentiation between impingement and instability is critical. Imaging findings guide planning, patient selection, and prognostication, supporting surgical interventions while minimizing risks. This review provides a structured overview of femoroacetabular impingement syndrome pathomechanics and imaging, highlighting conventional and advanced modalities, established and emerging diagnostic parameters, and their implications for patient-specific management.