Hip impingement, or femoroacetabular impingement (FAI), occurs when the femoral head (ball of the hip) pinches up against the acetabulum (cup of the hip). When this happens, damage to the labrum (cartilage that surrounds the acetabulum) can occur, causing hip stiffness and pain, and can lead to arthritis.
There are three types of FAI: pincer, cam, and combined impingement.
Both hip dysplasia and hip impingement (femoroacetabular impingement, or FAI) are, in fact, major causes of osteoarthritis in the young adult hip and often result in the need for surgical reconstruction or replacement of the joint (a procedure called arthroplasty) at a young age.
As the most common form of FAI, cam impingement occurs when a bone spur on the ball-shaped end of the femur head leaves it misshapen. When the femoral head isn't perfectly round, it collides with the acetabulum and can't move smoothly within the socket.
Cam-type femoroacetabular impingement (FAI) is a known cause of groin pain and a condition that can give rise to osteoarthritis of the hip (1). Patients suffering from this condition are mainly young and experience pain when the hip is moved through internal rotation and adduction at 90° of hip flexion.
Causes and Risk Factors FAI is caused by deformities in the femur, hip socket or a combination of both. The condition may begin at birth (congenital) or may develop as a child grows (acquired).
The hip joint (femoroacetabular joint) is a ball-and-socket joint located where the thighbone (femur) meets the pelvic bone. The upper segment (“head”) of the femur is a round ball that fits inside the cavity in the pelvic bone that forms the socket, also known as the acetabulum.
FAI is frequently seen in athletes. One recent systematic review of North American patients undergoing surgery for FAI found that the average age at surgery was 28 years and there was a mild female preponderance FAI at 55% of patients (9).
Treatment for hip impingement should begin with:Resting the affected hip.Modifying your activities to avoid moving the joint in a way that causes pain.Exercising as recommended by your doctor or physical therapist to strengthen the muscles that support the hip.More items...•
To confirm a diagnosis of FAI, your doctor may use: Imaging tests: Tests such as X-rays and MRIs help doctors identify abnormalities and signs of damage in the hip joint. Impingement test: Your doctor brings your knee up to your chest and rotates it toward the opposite shoulder.
The most common type of FAI occurs from mixed cam and pincer pathology at the anterior femoral neck and anterior superior acetabular rim.
Symptoms of FAIThere may be no pain or symptoms.Pain or aching (usually located at the inner hip, or groin area), usually after walking, or prolonged sitting (such as in a car)A locking, clicking or catching sensation within the joint.Pain sitting for long periods of time, like in a car.More items...