Femoroacetabular Impingement
Femoroacetabular impingement, commonly called FAI, occurs when the shape of the hip joint causes abnormal contact between the ball and socket during movement. It can lead to hip or groin pain, stiffness and difficulty with certain activities.
What is femoroacetabular impingement?
Femoroacetabular impingement is a condition in which abnormal contact occurs between the femoral head and the acetabulum. This may cause pain and restricted hip movement, particularly during deep flexion or rotational activities.
Early assessment can help identify the cause of hip pain and guide an appropriate treatment plan.
What Is FAI?
The hip is a ball-and-socket joint. The rounded head of the femur fits into the socket of the pelvis, allowing the hip to move in several directions.
In femoroacetabular impingement, the shape of the ball, socket or both can result in abnormal contact during certain hip movements.
Over time, repeated abnormal contact may irritate structures around the hip, including the labrum and joint cartilage. Not everyone with an abnormal hip shape develops symptoms.
Ball-and-socket hip joint
Hip and groin region
Flexion and rotation may provoke symptoms
FAI or hip impingement
Different Patterns of Hip Impingement
FAI is generally described according to the shape of the femoral head, acetabulum or a combination of both.
Cam Impingement
Cam impingement occurs when there is an abnormal shape or extra bone around the femoral head or neck. This can result in contact with the socket during certain hip movements.
Pincer Impingement
Pincer impingement occurs when there is increased coverage of the femoral head by the acetabulum, potentially causing abnormal contact during movement.
Combined Impingement
Some patients have features of both cam and pincer impingement. The significance of these findings depends on symptoms, examination and imaging rather than the shape alone.
Symptoms of Hip Impingement
Symptoms can vary from person to person and may become noticeable during sport, prolonged sitting or movements that require deep hip flexion.
Groin Pain
Pain is commonly felt deep in the groin or front of the hip and may increase during certain movements.
Hip Stiffness
Reduced hip mobility may make activities involving bending or rotating the hip more difficult.
Pain With Sitting
Prolonged sitting, particularly with the hip flexed, may aggravate symptoms in some patients.
Pain During Sport
Running, football, cricket, martial arts and other activities involving hip rotation may trigger pain.
Clicking or Catching
Some patients experience clicking, catching or other sensations around the hip.
Reduced Range of Motion
Certain movements, particularly deep hip flexion and rotation, may become uncomfortable or limited.
Causes & Factors Associated With FAI
The shape of the hip joint associated with FAI may develop during growth. Some people have these structural features without experiencing symptoms.
Repetitive activities involving deep hip flexion, rotation or high physical demands may contribute to symptoms in susceptible individuals.
How Is FAI Diagnosed?
Diagnosis usually involves combining the patient's symptoms with a physical examination and appropriate imaging studies.
Medical History
The specialist will discuss the location of pain, activities that trigger symptoms and how long the symptoms have been present.
Physical Examination
Hip movement, strength and specific movements that reproduce symptoms may be assessed during the examination.
Imaging
X-rays can help assess the shape of the hip joint. MRI or other advanced imaging may be recommended when soft-tissue or cartilage problems need further evaluation.
Treatment Planning
Symptoms, examination findings and imaging are considered together before deciding on the most suitable treatment approach.
Treatment for Femoroacetabular Impingement
Treatment depends on the severity of symptoms, activity requirements, examination findings and whether there is associated damage inside the hip.
Activity Modification
Temporarily modifying activities that repeatedly provoke hip pain may help reduce irritation and allow symptoms to settle.
Physiotherapy
A structured rehabilitation programme may focus on hip strength, movement control, flexibility and improving functional mechanics.
Pain Management
Appropriate measures to manage pain and inflammation may be recommended based on the patient's overall health and clinical assessment.
Rehabilitation
Gradual strengthening and return to normal activity can help improve hip function and confidence during movement.
Hip Arthroscopy
For selected patients whose symptoms do not improve with appropriate non-surgical treatment, hip arthroscopy may be considered to address specific structural or associated problems.
Individualised Treatment
The right treatment is determined by the patient's symptoms, activity goals, examination and imaging findings rather than an imaging finding alone.
Discuss Your Hip Pain →Managing Hip Pain During Activity
Certain movements may temporarily increase symptoms in people with hip impingement. Activities involving deep squatting, repeated pivoting or prolonged hip flexion may need to be modified depending on the individual.
A rehabilitation programme can help identify appropriate exercises and gradually improve strength, mobility and functional movement.
Explore Sports Injury Care →Move With Confidence
Persistent hip or groin pain during activity deserves a proper assessment rather than being repeatedly ignored.
When Should You See An Orthopaedic Specialist?
Consider an assessment if hip or groin pain continues, affects your daily activities or prevents you from participating in sports.
Book a Consultation →Persistent groin or hip pain
Pain while sitting for prolonged periods
Pain during squatting or hip rotation
Clicking or catching around the hip
Difficulty returning to sports
Frequently Asked Questions
What is femoroacetabular impingement? +
Femoroacetabular impingement, or FAI, is a hip condition in which abnormal contact occurs between the femoral head and the acetabulum during certain movements. It may cause hip or groin pain and restricted movement.
What are the symptoms of FAI? +
Common symptoms include pain in the groin or front of the hip, stiffness, reduced range of motion and discomfort during activities such as running, squatting, prolonged sitting or hip rotation.
What causes hip impingement? +
FAI is associated with the shape of the hip joint. Repetitive movements and high-demand activities may cause symptoms in people with certain hip structures.
What is the difference between cam and pincer impingement? +
Cam impingement involves an abnormal shape around the femoral head or neck, while pincer impingement involves increased coverage of the femoral head by the acetabulum. Some patients have features of both.
Can FAI be treated without surgery? +
Many patients can initially be managed with non-surgical measures such as activity modification, physiotherapy, rehabilitation and appropriate pain management. The best approach depends on the individual's symptoms and findings.
Does everyone with FAI need surgery? +
No. The presence of an abnormal hip shape on imaging does not automatically mean surgery is required. Treatment decisions should consider symptoms, examination findings, activity goals and associated joint problems.
Can FAI affect athletes? +
Yes. Athletes involved in sports requiring repeated hip flexion, rotation, pivoting and changes of direction may experience symptoms related to hip impingement.
When should I see an orthopaedic doctor for hip pain? +
An orthopaedic assessment is appropriate when persistent hip or groin pain interferes with daily activities, sitting, exercise, sport or normal hip movement.
Persistent Hip Pain Shouldn't Be Ignored.
Understand the cause of your hip or groin pain and explore appropriate treatment options with an orthopaedic specialist.