Femoroacetabular Impingement

Hip labral tears refer to tears in the soft tissue lining the acetabulum (bony socket) of the hip joint, known as the labrum. The labrum provides a suction seal for the hip joint, and this is important in joint lubrication, stress distribution and stability. Although hip labral tears can be caused by sports injury, trauma or hip dislocations, they are more commonly associated with femoroacetabular impingement and hip dysplasia.

Femoroacetabular Impingement (FAI) is a condition in which there is extra bone around the femoral head and neck (ball) and acetabulum (socket) of the hip joint. This extra bone may knock against each other during movement, damaging the cartilage and labrum of the hip joint in the process. FAI causes pain in the hip and limits activities and sports participation. In the long term, FAI may result in arthritis of the hip.

There are three types of FAI:

Pincer – this occurs when the extra bone extends out over the normal rim of the acetabulum (socket), resulting in the labrum being crushed and tearing under the prominent rim of the acetabulum.
Cam – this happens when the femoral head (ball) is not round or forms a bump on the edge of the femoral head-neck and cannot rotate well inside the acetabulum, resulting in grinding on the cartilage in the acetabulum.
Combined – both the pincer and cam types are present.

Symptoms

The common symptoms of FAI include:

Pain
Stiffness
Clicking
Limping

Pain can sometimes be dull, but often occurs in the groin area, and can also be felt toward the outside of the hip. Actions like turning, twisting, and squatting may cause a sharp, stabbing pain.

Causes

FAI occurs due to the hip bones not forming normally during childhood, yet some may live long, active lives with the condition and not encounter any problems.
However, for others, the deformity of the cam or pincer bone spur leads to joint damage and pain. When symptoms develop, it often points to the fact that there is damage to the cartilage or labrum and will most likely progress.

People who are athletic may begin to experience symptoms earlier as they tend to work the hip joint more vigorously, but it is important to note that exercise alone does not cause FAI.

Diagnosis

Your orthopaedic specialist will check for limitation in range of movement of your hip and perform an impingement test where your knee will be brought up to your chest and rotated inwards towards your opposite shoulder. If you feel pain in the hip, it means that the impingement test is positive. Your orthopaedic doctor will also check for any childhood hip conditions that may contribute to your symptoms or cause the impingement.

Your orthopaedic specialist will need to order imaging tests to help determine if you have FAI.

X-rays – show if you have any abnormally shaped bones and signs of arthritis
CT scans – more detailed and shows the exact abnormal shape of your hip
MRI scans – create better images of soft tissue and help your doctor identify damage to the labrum and joint cartilage

In cases where the origin of the hip pain is not clear, your orthopaedic specialist may perform a diagnostic hip injection (of local anaesthetic and steroid) under X-ray or ultrasound control – if the numbing medicine provides temporary pain relief, it suggests that FAI or an associated labral tear is the problem.

Treatment

The treatment for hip labral tears and FAI is dependent on the severity of your condition and the symptoms you experience. Ultimately, the main goal of treatment is to help you relieve pain, allow you to resume your usual activities and prevent permanent injury to your hip.

Your orthopaedic specialist may recommend nonsurgical (conservative) treatment, such as avoiding activities that cause symptoms, and taking anti-inflammatory drugs to reduce joint pain and inflammation. A short course of physical therapy will also help to strengthen the muscles surrounding the hip, and to relieve stress on the inflamed joint.

If conservative treatments prove to be ineffective or if the FAI is severe, your orthopaedic specialist may recommend surgery. Most hip labral tears and FAI can be treated with arthroscopic (keyhole) hip surgery, where small incisions are made, and a camera and specialised instruments are used to enter your hip joint. During the procedure, the torn labrum or damaged cartilage is repaired, and bony reshaping of the acetabulum (socket) and femoral head and neck (ball) is performed. This is a technically demanding procedure that should be performed by properly trained specialists, but compared to open surgery, the keyhole procedure results in less pain and joint stiffness and shortens the recovery time for patients. In good hands, most patients can expect to return to their regular activities including sports.

Every case is different; hence it is best to consult an orthopaedic surgeon for an accurate diagnosis so that you can obtain the best treatment option that is most suitable for you. Dr Poh is renowned for his experience in hip disorders around the region and has performed a high volume of hip arthroscopy cases. Reach out to us today if you suspect that you are suffering from a hip labral tear or FAI and let us help you enjoy a better quality of life.