Hip pain is a complaint we often hear in the orthopedic and physical therapy clinics. However, it is important to distinguish true hip joint pain and other sources. Often people complain of hip pain, when in fact their pain is located in the outer thigh, upper buttock or low back and is caused by structures other than the actual hip joint. When the pain is truly coming from the hip joint, the pain is normally located in the groin or outer hip right over the ball and socket joint.
The most common causes of hip pain are arthritis, stress fractures, tendonitis and bursitis. Arthritis can be seen on x-rays and is usually found in the older population. Stress fractures are often due to overuse and an increase or change in training. Tendonitis and bursitis can also be caused by overuse, but can also be the result of muscle imbalances. Physical therapy can assist with symptoms and recovery in all of these cases.
Another cause of hip pain is femoroacetabular impingement or FAI. FAI occurs when there is abnormal shape of the bones of the hip. FAI is more prevalent than initially thought and presents most commonly in active individuals between 20 and 50. FAI is a condition which causes too much friction in the hip joint which causes pain, limited range of motion, muscle weakness and impaired movement patterns. It is also associated with labral tears, cartilage damage and OA.
Normal anatomy of the hip includes the acetabulum (which is part of the pelvis, and forms the socket) and the femoral head (which is the upper end of the femur or thigh bone). The acetabulum is surrounded by a strong fibrocartilage (labrum), which produces a suction or tight seal, and stability for the joint. The joint also has articular cartilage which decreases friction by giving smooth surfaces to the bones of the joint.
There are 3 types of FAI. CAM-type FAI occurs when the head of the femur is abnormally shaped. Pincer-type FAI is when there is too much coverage of the acetabulum over the femur. Third type is combined, which is having both cam-type and pincer-type at the same time. These cause unwanted contact between the bones when the patient moves the hip and can pinch other structures, such as the labrum. See Pictures here.
Symptoms of hip FAI often begin with a feeling of stiffness and loss of the hip’s full range of motion. Initially, pain may only be present with moving your hip to its end ranges and pain can be sharp/stabbing or just a dull ache, usually in the groin. As it becomes worse, symptoms can be felt with prolonged sitting, walking (especially uphill), squatting, bending or pivoting on the limb.
Non-surgical treatment for femoroacetabular impingement include rest, activity modification, ice, physical therapy to improve biomechanics, such as strength and flexibility. Sometimes intra-articular injections can also help with symptoms. However, this will not change the bony abnormality and continued joint damage may occur.
Surgical treatment is recommended in patients that have failed conservative treatment and have ongoing pain and physical limitations. Surgery can be performed arthroscopically or open. Arthroscopic surgery avoids a large incision, using portal sites to access the joint with instruments and a camera to visualize the area being worked on. This is done to shave down extra bone on the femur or to trim the rim of the acetabulum, as well as to fix or shave the labrum if it is damaged. When a full open surgery is required the head of the femur is dislocated from the socket and then the work is performed. The decision of which surgical technique to be utilize is often dependent on the type of impingement, the extent of the impingement, the imaging done pre-operatively, and the opinion of the surgeon performing the procedure.
FAI surgical procedures normally require 3-4 months before full unrestricted activity is allowed. However, this is dependent on type of surgery, extent of joint damage, anticipated activity level and if the procedure was your first or if it was a revision.
After surgery, the patient is often on crutches for several weeks, again depending on the type of surgery performed. Rehabilitation with formal physical therapy is essential for full recovery without having problems down the road. They can help to restore full range of motion of the hip safely, help increase strength and normalize biomechanics and movement patterns, in order to return prior activity level and lifestyle.