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Please ask a qualified health professional about symptoms, treatment decisions, or concerns about your own condition.
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Bones & Joints
Pincer FAI - hip socket (acetabulum) over-covers ball of hip joint causing pinching of labrum and cartilage with movement. More common in middle-aged athletic women (30-50s), dancers, gymnasts. Excessive socket coverage (deep socket or retroverted tilted backward) causes edge of socket to contact femoral neck with hip flexion, crushing labrum rim. Symptoms: deep groin pain with sitting/walking/sports, reduced hip flexion and internal rotation, C-sign. Diagnosis: X-rays show crossover sign (anterior wall crosses posterior wall), prominent anterior wall, lateral center-edge angle over 40 degrees. MRI arthrogram shows labral tears at anterosuperior labrum (front-top rim where pinching occurs). Treatment: activity modification and physiotherapy first 3-6 months (30-50% improve). Surgery: hip arthroscopy with acetabuloplasty (trim excessive socket rim) and labral repair. Outcomes: 75-85% good results if young (under 40) with minimal arthritis and both pincer correction + labral repair performed. Poorer outcomes (50-60%) if age over 50 or arthritis present. Often coexists with cam FAI (mixed FAI 85% of cases) requiring correction of both bone abnormalities.
What it is and why it happens
Pincer FAI - hip socket (acetabulum) over-covers ball of hip joint causing pinching of labrum and cartilage with movement. More common in middle-aged athletic women (30-50s), dancers, gymnasts. Excessive socket coverage (deep socket or retroverted tilted backward) causes edge of socket to contact femoral neck with hip flexion, crushing labrum rim. Symptoms: deep groin pain with sitting/walking/sports, reduced hip flexion and internal rotation, C-sign. Diagnosis: X-rays show crossover sign (anterior wall crosses posterior wall), prominent anterior wall, lateral center-edge angle over 40 degrees. MRI arthrogram shows labral tears at anterosuperior labrum (front-top rim where pinching occurs). Treatment: activity modification and physiotherapy first 3-6 months (30-50% improve). Surgery: hip arthroscopy with acetabuloplasty (trim excessive socket rim) and labral repair. Outcomes: 75-85% good results if young (under 40) with minimal arthritis and both pincer correction + labral repair performed. Poorer outcomes (50-60%) if age over 50 or arthritis present. Often coexists with cam FAI (mixed FAI 85% of cases) requiring correction of both bone abnormalities.