Figure 1. Anteroposterior radiograph of the hip; arrow points to a prominence at the femoral head/neck junction.
A 52-year-old man presents with right hip pain for the past 3 months. He works in construction and does a lot of bending and squatting but denies a known injury. The patient notes that the pain can be sharp and intense at times and is usually located in the groin. On physical examination, the patient has pain with hip flexion, adduction, and internal rotation. An anteroposterior radiograph of the right hip shows a prominence at the femoral head/neck junction indicated by a white arrow (Figure).
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Femoroacetabular impingement (FAI) occurs when extra bone forms at the femoral head/neck junction and/or the acetabulum. The extra bone can cause abutment of the femoral head/neck junction and the acetabular rim during hip flexion and internal rotation. Repetitive contact between the bones can cause pain, decreased range of motion, labral abnormalities, and chondral wear.1-3
Extra bone at the femoral head/neck junction is called a cam lesion. Extra bone on the acetabulum is called a pincer lesion. Patients may present with just 1 lesion; however, up to 80% of patients have both lesions (combined cam/pincer impingement).1-3
If a symptomatic cam lesion is present and patients have failed at least 3 months of conservative treatment, an arthroscopic osteoplasty may be performed to trim down the extra bone. Hip arthroscopy is not indicated in patients with underlying hip arthritis.1-3
Dagan Cloutier, MPAS, PA-C, practices in a multispecialty orthopedic group in the southern New Hampshire region and is editor in chief of the Journal of Orthopaedics for Physician Assistants.
1. Horisberger M, Brunner A, Herzog RF. Arthroscopic treatment of femoroacetabular impingement of the hip: a new technique to access the joint. Clin Orthop Relat Res. 2010;468(1):182-190. doi:10.1007/s11999-009-1005-5
2. Kweon C, Welton KL Kelly BT,Larson C, Bedi A. Arthroscopic treatment of cam-type impingement of the hip. JBJS Rev. 2015;3(9):e3. doi:10.2106/JBJS.RVW.O.00006
3. Steffes MJ, Abbasi D. Femoroacetabular impingement. OrthoBullets. Updated April 16, 2021. Accessed April 21, 2021. https://www.orthobullets.com/knee-and-sports/3130/femoroacetabular-impingement