When otherwise healthy young and middle-aged adults—particularly those who have participated in sports—develop hip stiffness and hip or groin pain, the cause may be hip impingement, or femoro-acetabular impingement (FAI). FAI can be caused by repetitive use or by bone abnormalities from an old injury to the hip. The pain may occur when a person gets in and out of a car, reaches to put on shoes and socks, or sits for a prolonged period.
The pain can be chronic or acute. Left untreated, FAI can lead to early osteoarthritis of the hip and, eventually, the need for total hip replacement.
FAI gets its name from the anatomy of the hip and thigh. The head of the femur, or thigh bone, fits into a socket in the hip called the acetabulum. Both bones are lined with cartilage that allows the joint to slide smoothly. In addition, the acetabulum has an additional layer of cartilage called the labrum that helps grip the head of the femur and hold it in place.
Hip impingement can occur in two ways:
- In cam impingement, the head of the femur is not completely smooth and/or round. Over time, the head rubs against the acetabular lining and damages the labrum, causing pain.
- In pincer impingement, the acetabulum is abnormal in its shape or smoothness. Over time, the acetebulum rubs against the femoral lining, damaging the cartilage and reducing the range of motion.
Arthroscopic surgery to smooth bone irregularities usually brings significant relief to people with moderate hip impingement. Following surgery, physical therapy is essential to prevent scar tissue formation, restore range of motion and develop strength in the hip.
Most people return gradually to everyday activities after about six weeks, although soreness may last several months. We can develop a realistic and manageable rehabilitation program to help restore hip movement and allow you to resume your normal activities— healthy and pain-free.
