The relationship between cam morphology and hip and groin symptoms and signs in young male football players

Background: Conflicting and limited high-quality prospective data are available on the associations between cam morphology and hip and groin symptoms and range of motion (ROM).

Objectives: This cross-sectional cohort study investigated associations between cam morphology presence, size and duration and symptoms and ROM.

Methods: Academy male football players (n = 49, 17-24 years) were included. Standardized antero-posterior pelvic and frog-leg lateral radiographs were obtained at baseline, 2.5- and 5-year follow-up. The femoral head-neck junction was quantified by: Visual score. Cam morphology (flattening or prominence), large cam (prominence). Alpha angle. Cam morphology (≥60°), large cam (≥78°). Cam morphology duration was defined as long (first present at baseline) or short (only from 2.5- to 5-year follow-up). Current symptoms at 5-year follow-up were assessed using a hip and groin pain question and by the "Hip and Groin Outcome Score" (HAGOS). HAGOS scores were categorized into: most symptoms (≥2 domains in lowest interquartile range [IQR]), least symptoms (≥2 domains in highest IQR). Hip ROM was measured by goniometry at 5-year follow-up.

Results: Large cam morphology based on visual score was associated with hip and groin pain (23.8% vs. 7.1%, OR: 3.17, CI: [1.15-8.70], P = .026), but not with HAGOS scores. Cam morphology presence, size, and duration were associated with limited flexion of around 6° and/or 3° to 6° for internal rotation.

Conclusion: Cam morphology presence, size, and duration were associated with limited hip flexion and/or internal rotation, but differences might not exceed the minimal clinical important difference. Whether cam morphology results in symptoms is uncertain.