Athletic Hip Impingement

None — The Hip

The hip is a ball and socket joint that connects the upper thigh bone (femur) with the pelvic bone. The upper end of the femur has a rounded head that rotates inside a socket in the pelvic bone (called the acetabulum). Strong ligaments surround the hip joint to hold the bones in place.

The ball and socket are lined with a thin, tough layer of cartilage that cushions and protects the bones and prevents them from rubbing together. In addition, the rim of the socket is lined with a fibro cartilaginous rim, called the labrum. The labrum acts like a gasket to grip the head of the femur and keep the bone in proper position inside the socket.

Hip Impingement

Hip impingement (femoroacetabular impingement, or FAI) is a condition in which the ball and socket are unable to properly and smoothly move in a full range of motion. It occurs when there is some type of abnormality in the joint, allowing the bones to rub together. There are two forms: cam-type and pincer-type. In the cam-type the head and/or neck of the thigh bone isn't completely round, interfering with the ability of the femoral head to properly rotate within the socket. In the pincer-type, the rim of the socket is poorly angled or overgrown, extending the rim, and making the socket too deep. The joint cartilage becomes "pinched" between the rim and femoral head.

The incidence of hip impingement isn't known, nor is the cause. Researchers theorize the condition is either the result of a congenital abnormality or from physical impact during growth spurts. When the bones continually rub, the cartilage and labrum (rim) can tear. Eventually, the head of the femur can rub the pelvic bone, causing hip pain (from the front, side or back) and loss of motion. The pain may be more noticeable after sitting or walking, especially when walking uphill. In some cases, the pain may radiate along the thigh and into the buttocks. Eventually, the condition can lead to the development of arthritis in the affected joint.

Athletes and Hip Impingement

Hip impingement is a condition that is sometimes seen in older people. However, doctors are seeing an increasing number of cases in young athletes. Researchers believe repetitive pivoting and flexing of the hips may cause tears in the labrum or cartilage, leading to hip impingement. Some sports commonly associated with hip impingement include: football, baseball, soccer, tennis, golf, dance, hockey (ice and field) and lacrosse.

Diagnosis of hip impingement is typically made after taking a thorough history, X-rays and MRI scans. If the condition is confirmed, doctors may initially try conservative therapy. This may involve rest, modification of activities, physical therapy and/or use of anti-inflammatory medications. Shane Nho, M.D., Orthopaedic Surgeon with Rush University Medical Center in Chicago, IL, says conservative therapy often works better for middle-aged and older adults, who tend to be less active than younger patients.

When conservative therapy fails to produce significant or long-term symptom relief, doctors may recommend surgery. In the traditional, open surgery approach, a long (6 to 10 inches) incision is made into the side of the hip and the hip is dislocated. Doctors can then get a good look at the cause of the symptoms and make a repair.

Arthroscopic Repair for Athletes

Open surgery is often not recommended for young athletes or those who expect to have significant activity levels after surgery. For these patients, doctors may recommend arthroscopic repair. Two to four small incisions are made into the side of the hip. Then, using special surgical instruments, damaged structures can be repaired. Torn or fragmented bits of bone and tissue may be shaved away. In areas where cartilage is lost, holes may be drilled into the bone (a process called microfracture) to promote the formation of new cartilage.

Nho says the key to success for arthroscopic treatment of hip impingement is a good program of rehabilitation. Even though the incisions are small, there's a great deal of manipulating inside the joint, which causes a significant amount of pain and weakness in the joint. Crutches are generally used immediately after surgery to limit weight and pressure on the joint. Physical therapy is ordered two times a week for at least three months. If patients are sports participants, the physical therapy will include activities specifically geared to protect the hip and improve the athlete's ability to function in that sport. It can take three to six months for a patient to be able to return to normal activities. According to Nho, over 90 percent of athletes who have arthroscopic surgery for hip impingement, and then successfully complete their rehabilitation program are able to return to the same level of play.

For general information on hip problems:

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