The hip is ball and socket joint which provides both movement and stability as individuals go about their daily activities. It is made up the femoral head (the ball shaped top upper segment of the femur) and the acetabulum (the concave socket of the pelvic bone.) Normally, the femoral head is held tightly in the socket with strong ligaments, as well as a fibrocartilaginous pad called the labrum. Both bones are covered with a thin layer of cartilage which cushions the joint, allowing smooth, pain free movement.
When healthy, all of these elements work together to allow regular motions like standing, walking, and climbing stairs. However, if a patient begins to experience limited motion and pain, it may be time to talk to a doctor at Rothman Institute about femoral acetabular impingement (FAI), otherwise known as hip impingement.
What Is Hip Impingement?
Femoral Acetabular Impingement (FAI), or hip impingement, can be the result of subtle abnormalities in the hip and may lead to osteoarthritis in younger patients. FAI is the abnormal friction or contact between the femoral head and the acetabular margin. This abnormal friction, in turn, causes tearing of the labrum and the underlying cartilage. The ultimate result of the continued deterioration, if untreated, is the bones of the joint rubbing together as arthritis sets in.
There are two different kinds of impingement that can develop in the hip. The first, CAM impingement, occurs when a larger or abnormally shaped femoral head is jammed into the acetabulum. This jamming then results in the avulsion of the labrum. CAM impingement is the more common form of FAI. Pincer Impingement, on the other hand, results from abnormal shape or rotation of the acetabulum or cup. This results in increased contact between the femoral head and the labrum, which lives on the rim. Eventually the labrum can tear, which is when symptoms typically begin.
How Do I Know If I Have FAI?
FAI can occur at any time between the teenage years and middle age. However, it usually occurs in young athletic patients, often after a minor trauma. Initially, patients may notice an intermittent pain in the front of their hip or groin area. Then, the pain may worsen after excessive use of the hip, whether through physical exercise or an extended period of sitting. Other symptoms may include:
- Pain after prolonged sitting
- Pain after athletics
- Difficulty walking up hill
- A consistent dull ache with or without a catching or popping sensation
If a patient is experiencing these symptoms, he or she should talk to a doctor. In order to diagnose FAI, the doctor will begin with a physical examination of the hip which often reveals its limited range of motion. X-ray and MRI tests are also important stages in diagnosing hip impingement. An X-ray can reveal the excess of bone on the acetabular rim or the femoral head and neck. It is important to have weight-bearing X-rays with special views to properly diagnose FAI. An MRI or MR arthrogram, where dye is injected into the hip prior to the MRI, reveals tears of the cartilage and labrum.
Can FAI Be Treated?
Typically, surgical treatment is required to address these symptoms. FAI may be treated with hip arthroscopy of through an open procedure. The goal of either approach is hip preservation, which means repairing the damage to preserve the natural hip structures. With hip arthroscopy, the damaged labrum may be repaired. At the same time, the bony malformation from the FAI may be decompressed removing the bony prominence. Femoral Acetabular Osteoplasty may be done with an open surgical procedure which removes a prominent area of bone from the femoral neck. Either procedure restores the femoral neck clearance and free range of motion for the affected hip. The goal is to reduce the patient's pain and to prevent any further damage to the cartilage from occurring, thus preserving the hip (Hip Preservation).
Patients eligible for this treatment include those who are too young for a total hip replacement and also patients who do not yet have significant arthritis in the hip. Those patients with evidence of arthritis are NOT candidates for any FAI surgery, arthroscopic or open. Still, significant work is being done in the research of cartilage regeneration, with the hopes of such advancements being available in the future.
Where Can I Seek Treatment?
If you or someone you love is suffering from hip impingement, turn to Rothman Institute for the most advanced treatment and care. Our hip specialists have the focused experience necessary to provide you with the highest level of treatment. As leaders in orthopaedic research, we incorporate the latest developments in science and technology in each procedure. And, as caring doctors, therapists, and surgeons, we will be there to care for you and help you get back on your feet.