Hip Impingement Syndrome
One of the leading causes of hip pain is hip impingement, which occurs when there is abnormal contact between the bones of your hip joint.
We’ll cover the following on this page:
- What Is Hip Impingement Syndrome?
- Types of Hip Impingement
- Symptoms of Hip Impingement
- Hip Impingement Risk Factors
- Hip Impingement Diagnosis
- Treatment Options
What Is Hip Impingement Syndrome?
Femoroacetabular impingement (FAI), or simply hip impingement, is a condition where the ball of the hip (femoral head) pinches or rubs against the socket of the hip (acetabulum). This occurs due to anatomic bony variability of the ball and socket of the joint. When these two bones rub against each other during certain movements of the hip, they can pinch and damage the labrum, which is a thick ring of cartilage that lies between the femoral head and acetabulum. Labral tears can result in significant hip pain and stiffness. Eventually, this can lead to the advancement of osteoarthritis as joint wear-and-tear occurs.
Types of Hip Impingement
Hip impingement syndrome can be classified as follows:
- Cam Impingement: Cam impingement is due to a deformity of the femoral head, or ball, of the hip joint. Rather than being perfectly round, the femoral head takes a non-spherical shape, which does not fit well within the socket. As a result, the excess bone of the femoral head and neck rubs against the socket of the hip joint during certain movements, pinching the labrum.
- Pincer Impingement: With Pincer impingement, the hip socket extends too far over the femoral head, leading to overcoverage. This causes the edge of the socket to pinch against the femoral head, again entrapping and damaging the labrum.
- Combined Impingement: In some hips, both Cam and Pincer deformities are present. As a result, the non-spherical femoral head continually rubs against the overextended hip socket
Symptoms of Hip Impingement
Hip impingement can present differently in different individuals. In many cases, hip impingement can even be asymptomatic. However, when symptoms do occur, there is a common pattern:
- Pain: People may experience varying degrees of pain, typically in the groin area. This is often indicative of damage within the joint, like a labral tear. Pain may occur at rest and can also occur with movements like walking, sitting, stair-climbing, or pivoting. Some patients experience a sharp, stabbing sensation, while others experience a dull, lingering pain.
- Instability: Some patients describe a feeling that their leg may give out due to instability of the hip joint.
- Clicking or Popping Sounds: Since the structures of the hip joint rub against each other with hip impingement, you may hear audible clicking and popping sounds as you walk, run, and perform other activities.
- Stiffness: You can feel stiffness or a locking sensation in the hip joint, making it difficult to move your leg in certain directions.
- Limited Range of Motion: Impingement can also limit how far the hip joint can move in any direction. Forcing the joint to move can cause further sharp pain.
Hip Impingement Risk Factors
Certain risk factors can increase the likelihood of hip impingement syndrome:
- Genetics and Abnormal Hip Anatomy
When the femoral head or acetabulum develop abnormally, it can lead to hip impingement. - Prior Hip Conditions
Previous hip conditions, like slipped capital femoral epiphysis (SCFE), can contribute to the development of hip impingement due to bony abnormalities. - Repetitive Activities
High-impact sports, bending, squatting, and other repetitive hip motions can lead to damage and deformities in the hip joint. These activities can increase one’s risk of developing hip impingement.
Hip Impingement Diagnosis
Providers can review your medical history and assess your symptoms as a first step to evaluating for hip impingement.
Through a comprehensive physical examination, providers can gauge your pain level and range of motion in the hip. X-rays can be performed to visualize the bony anatomy of the femoral head and acetabulum to confirm or rule out hip impingement. Further imaging modalities, including MRIs and CT scans can provide additional information regarding impingement in the hip.
Treatment Options
After a diagnosis of hip impingement, doctors will first recommend non-invasive conservative treatment plans, especially if the symptoms aren't well pronounced. Physical therapy and/or anti-inflammatory medications may be prescribed as part of your treatment plan.
However, if these treatments do not relieve symptoms, your doctor may recommend surgery. Surgery for FAI has two purposes: (1) to address any damage within the hip joint, and (2) to correct the bony anatomy causing the impingement. Arthroscopic hip surgery can achieve both of these goals. Through a few small incisions, the labrum can be repaired, and the excess bone in the joint can be shaved down. Trimming the excess bone around the femoral head and neck (Cam deformity) to restore its spherical contour is known as a femoroplasty, and trimming the overhang of the acetabular rim (Pincer deformity) is known as an acetabuloplasty. As a result of these procedures, patients can experience pain relief due to the restoration of the labrum and a renewed ability of the ball-and-socket joint to move in all directions without the friction of impingement.
Work With Trusted Hip Specialists
Dr. Benjamin Domb is a trusted orthopedic surgeon in Greater Chicago who specializes in hip arthroscopy and sports medicine. Dr. Domb is an expert in minimally invasive surgical procedures to resolve hip impingement. Our team can get you moving pain-free in no time. Contact us today to schedule a consultation.