MRI NEWSLETTER: High Incidence of CAM FAI in Athletes

Posted April 4, 2017

Recent studies of FAI reveal the very high incidence of cam deformity (femoral neck bump) in Athletes. The cam deformity is a major risk factor for osteoarthritis of the hip and labral tears.  More than half of the athletes studied, average age 25, had evidence of cam deformity as compared to only 23% of age-matched controls.  In one study, cam deformities gradually developed during maturation of the skeleton in young soccer players, suggesting playing soccer was causative of CAM.

Young patients with labral tears nearly always have FAI, most commonly cam deformity. 90% of labral tears and chondral defects occur at the anterior-superior portion for the acetabulum.

Cam impingement is caused by a nonspherical head. Pincer impingement is caused by excessive acetabular coverage. Most patients (85%) have a combination of both. Both result in limited hip motion. 50% of young athletes have FAI, most have cam deformity. Nearly all young people with labral tears have FAI. 90% of labral tears occur at the anterior-superior portion for the acetabulum.

There are 2 main types of labral tears. Type 1 involves the attachment of the articular hyaline cartilage from the fibrocartilagenous labrum at the transition zone. Type 2 labral tears are of the substance of the labrum.

CAM deformity appears to be caused by abutment of the femoral head-neck junction against the acetabulum bump, the nonspherical deformity of the femoral head. The bump lifts up the labrum and can shear the articular cartilage from the labrum resulting in chondral injury and labral tear.

Surgical studies suggest that debridement of labral tears in young people relieve hip pain in about 65% of cases, however if the labral tear can be repaired, pain is relieved in about 88% of patients. Type 1 tears at the attachment of the articular hyaline cartilage with the fibrocartilaginous labrum may be easier to repair.

Read the full article here High Incidence of CAM FAI in Athletes

By Dr. William Renner