Hip impingement is a structural or mechanical disorder of the hip. The hip joint is made up of the femoral head (ball) and the acetabulum (socket). An impingement condition occurs when the ball does not glide smoothly within the socket. This may be due a structural variation in the shape of the bones, or due to changes in muscle length and activation at the hip.
Hip impingement may be due to genetic bony abnormalities of the hip joint, to adaptations of muscle function surrounding the hip, or a combination of both.
- Cam impingement (structural) occurs because the ball shaped end of the femur (femoral head) is not perfectly round, this interferes with femoral head’s ability to move smoothly within the socket.
- Pincer impingement (structural) occurs due to an overdeveloped socket structure (acetabulum). The extra bone of the acetabulum will pinch the femoral head as it moves in the socket
- Adaptive impingement (muscle function) often occurs as a result of dysfunctional posture and muscle strength, contributing to compression by the femoral head on the structures in the front of the hip.
Symptoms from hip impingement may be vague initially, and progress with increasing activity, age, and tissue damage. Symptoms may include:
- Stiffness in the hip, thigh, or groin
- Structural limit or pain with flexing the hip above a 90-degree angle
- Pain in the front of the hip or groin during activity, especially during repetitive use activities, prolonged sitting, or movements requiring end ranges of motion
- Popping, clicking, or grinding in the hip during movement, which may be associated with damage to the labrum as a result of repetitive impingement
The ability to treat hip impingement conservatively will depend on the underlying mechanism of the impingement. Some things you can do on your own, regardless of the type of impingement, include:
- Avoid sitting with your knees higher than your hips, or in a “slumped” position
- Avoid prolonged sitting
- Avoid standing with your knees locked
- Modify or avoid painful activities
A physical therapist can perform a thorough assessment of movement patterns at your hip, pelvis, and back, and determine how your movement quality, and muscle length or strength, may be contributing to your impingement. Physical therapy is a good first step to treating hip impingement, even if the underlying cause is a structural change in the shape of the hip joint. Physical therapy for hip impingement may include:
- Changes in the way you sit, stand, or move with daily or recreational activities can take the stress off the hip joint. This can facilitate tissue healing and reduce pain.
- Soft tissue treatment: Hands on treatment of muscles surrounding the region of your hip impingement symptoms will assist with reducing pain, improving muscle relaxation, and improving the ability of joints to move normally.
- Joint mobilization: Hands on treatment focused at the level of the joint surfaces to reduce pain, improve joint specific mobility, and re-educate proper joint movement. This may be targeted at the hip as well as above and/or below the level of your symptoms to address contributions to your specific problem.
- Neuromuscular re-education: Training targeted at re-educating faulty movement patterns, improving muscle coordination, or facilitating muscle firing in muscles that are weak or inhibited. These movements are often small in nature and not targeted at making muscles bigger.
- Stabilization: Exercises targeting strength and endurance of the muscles closest to your joints (and therefore better at stabilizing joints than moving them).
- Activity training: Exercises targeted to your specific goals, fitness activities, recreational activities, or job requirements that will facilitate return to your lifestyle prior to pain.
- A physical therapist can assist in determining when your symptoms may be due to underlying bony changes, limiting the gains you can make in physical therapy. In this instance, you might need imaging, and to have a discussion with a doctor about when an injection or surgery would be appropriate.