Hip Impingement: Understanding FAI, Symptoms, and Relief
Updated: 2 days ago
Medically reviewed by Dr. Baraa Alnahhal, MD · Last reviewed: October 15, 2026
Quick Answer
Hip impingement is a mechanical issue within the hip joint where extra bone growth or an unusual joint shape causes painful pinching and rubbing [1]. Known medically as femoroacetabular impingement (FAI), it occurs when the ball and socket of the hip do not move smoothly against each other, often leading to groin pain and reduced range of motion [1].
What the research says
Surgery beat physiotherapy in the largest trial, but both helped. In the UK FASHIoN trial of 348 patients, hip-related quality of life (iHOT-33) at 12 months rose from 39.2 to 58.8 with arthroscopy and from 35.6 to 49.7 with personalized physiotherapy, an adjusted difference of 6.8 points (95% CI 1.7 to 12.0) that exceeded the 6.1-point minimum clinically important difference (Griffin et al., Lancet, 2018) [2].
Pooled trials favor arthroscopy for function and quality of life. A meta-analysis of three randomized trials (644 patients) found better iHOT-33, daily-living and sport scores after arthroscopy than after physiotherapy, with no significant difference in later total hip replacement (p = 0.72) (Gatz et al., Eur J Orthop Surg Traumatol, 2020) [3].
The bone shape alone does not always cause symptoms. A systematic review of 60 imaging studies found signs of FAI in athletes, symptomatic patients, and asymptomatic people alike, although cam morphology was significantly more common in symptomatic than asymptomatic people (p = 0.009) (Mascarenhas et al., Eur J Radiol, 2016) [4].
Key Takeaways
Category | Details |
Primary Cause | Structural bone spurs or congenital joint shape [1]. |
Common Symptoms | Groin pain, hip stiffness, and limping [1]. |
Types of FAI | Cam (femur spur), Pincer (socket spur), or Combined [1]. |
Diagnosis | Physical exam (FAI test) and imaging (X-ray, MRI) [1]. |
Main Treatments | Physical therapy, NSAIDs, and hip arthroscopy [1]. |
Long-term Risk | Increased likelihood of labral tears and osteoarthritis [1]. |
Understanding Hip Impingement (FAI)
The hip is a ball-and-socket joint designed for a wide range of motion. In a healthy joint, the head of the thigh bone (femur) fits perfectly into the socket (acetabulum) of the pelvis. Hip impingement occurs when this fit is compromised by extra bony growth, leading to abnormal contact and friction during movement [1]. This condition is often present from birth or develops during the growth years, though symptoms may not appear until later in life when the joint is subjected to repetitive stress [1].
Healthcare providers categorize FAI into three distinct types based on the location of the structural abnormality. Cam impingement involves extra bone growth on the neck of the femur, while pincer impingement occurs when the rim of the hip socket extends too far over the femoral head [1]. Many patients experience combined impingement, where both structural issues are present simultaneously [1].
Symptoms and Warning Signs
The most frequent indicator of hip impingement is a persistent, dull ache located deep within the hip or groin area. This pain can radiate outward to the thighs or buttocks, often feeling like a bruise that never quite heals [1]. Patients frequently report sharp, stabbing sensations when performing specific movements that involve deep hip flexion or rotation, such as squatting, lunging, or jumping [1].
Beyond pain, FAI often manifests as significant stiffness in the hip joint, making it difficult to perform daily tasks like putting on socks or getting in and out of a car. Some individuals may notice a limp or a “catching” sensation within the joint [1]. It is important to note that symptoms can be intermittent and may worsen significantly after prolonged periods of sitting or intense physical activity [1].
Causes and Risk Factors
Most cases of hip impingement are rooted in the natural development of the hip bones. Many individuals are born with an unusually shaped joint, and bone spurs can continue to develop over time [1]. While anyone can be affected, statistical trends show that cam impingement is more prevalent in males, whereas pincer and combined types are more common in females [1].
Athletes and highly active individuals are at a higher risk of experiencing symptoms earlier. Sports that require repetitive hip rotation and deep flexion—such as soccer, hockey, and dance—put significant pressure on the joint, making structural issues more apparent [1]. While the activity itself does not cause the impingement, the intensity of use accelerates the wear and tear on the joint's protective cartilage [1].
Complications and Long-Term Health
If left unmanaged, hip impingement can lead to progressive damage within the joint. The constant friction often results in labral tears, where the ring of cartilage lining the hip socket is gouged or torn by the abnormal bone contact [1]. Over time, this degradation increases the risk of developing osteoarthritis, as the protective cushioning between the bones wears away [1]. Early intervention is critical to preserving joint health and maintaining a high quality of life.
Diagnosis and Testing
Diagnosing FAI begins with a comprehensive physical evaluation. Healthcare providers typically use the FAI test, where the patient lies on their back while the provider lifts and rotates the leg to check for pain and restricted motion [1]. This maneuver puts light pressure on the areas most likely to be affected by impingement, helping to confirm the source of the discomfort [1].
Imaging is essential to visualize the structural changes in the joint. X-rays are used to identify bone spurs, while MRI and CT scans provide detailed views of the soft tissues and the extent of any cartilage damage [1]. In some cases, a diagnostic injection of local anesthetic is used; if the pain is temporarily relieved, it confirms that the hip joint is the primary source of the symptoms [1].
Treatment and Recovery Options
Management strategies for hip impingement range from conservative therapies to surgical intervention, depending on the severity of the symptoms and the extent of joint damage.
Treatment Type | Description | Goal |
Activity Modification | Avoiding deep squats or high-impact jumping. | Reduce joint friction and irritation [1]. |
Physical Therapy | Exercises to strengthen hip and core muscles. | Improve joint stability and mobility [1]. |
Medication | Over-the-counter NSAIDs or cortisone shots. | Manage pain and reduce inflammation [1]. |
Hip Arthroscopy | Minimally invasive surgery to reshape bone. | Correct the structural cause of FAI [1]. |
For many, physical therapy is highly effective in stabilizing the hip and reducing the load on the joint [1]. However, if non-surgical methods fail to provide relief, hip arthroscopy is a successful option. During this procedure, surgeons use small incisions to reshape the bone and repair any labral tears, allowing the joint to move smoothly once again [1].
Conclusion
Hip impingement is a manageable condition that, when addressed early, has a very high success rate for recovery. Whether through dedicated physical therapy or modern surgical techniques, most individuals are able to return to their active lifestyles and sports without long-term limitations. Understanding the structural nature of the pain is the first step toward effective relief and long-term joint preservation.
FAQ
What is the most common sign of hip impingement?
A dull ache in the groin or hip that worsens with activity. [1]
Can FAI be cured without surgery?
Symptoms can be managed, but the bone shape only changes with surgery. [1]
Is hip impingement the same as arthritis?
No, but it can lead to arthritis if untreated. [1]
Who is most at risk for FAI?
Athletes and individuals born with unusually shaped hip joints. [1]
What does an FAI test involve?
Lifting and twisting the leg to check for pain in the hip joint. [1]
Are cam and pincer impingements different?
Yes, cam affects the thigh bone; pincer affects the socket. [1]
How long does physical therapy take for FAI?
It varies, but several weeks are usually needed to see results. [1]
Is hip arthroscopy a major surgery?
It is minimally invasive, using small incisions. [1]
Can children have hip impingement?
Yes, it often develops during growth years. [1]
Does sitting for long periods make FAI worse?
Yes, it can cause sharp or stabbing pain. [1]
What medications help with FAI?
NSAIDs like ibuprofen and prescription corticosteroids. [1]
Can FAI cause lower back pain?
Pain can radiate, but it is primarily felt in the hip and groin. [1]
Is limping common with FAI?
Yes, due to pain and restricted movement. [1]
What is a labral tear?
A tear in the cartilage lining the hip socket. [1]
Can I still play sports with FAI?
Yes, though you may need to modify your activities. [1]
How is FAI diagnosed?
Through physical exams and imaging like X-rays and MRIs. [1]
What is combined impingement?
Having both cam and pincer types at once. [1]
Does FAI always cause symptoms?
No, some people have the bone shape but no pain. [1]
What happens if FAI is left untreated?
It can lead to labral tears and osteoarthritis. [1]
Is a cortisone shot a permanent fix?
No, it provides temporary inflammation relief. [1]
What exercises are best for FAI?
Strengthening exercises for the hip, glutes, and core. [1]
Can FAI be prevented?
No, as it is often related to natural bone development. [1]
What is the success rate of FAI surgery?
It is very high, with most patients returning to activity. [1]
Does FAI affect one or both hips?
It can affect one side or both. [1]
What does the pain feel like?
Like a deep bruise or a sharp pinch. [1]
Can FAI cause knee pain?
Pain can sometimes radiate, but the source is the hip. [1]
How do X-rays help diagnose FAI?
They show the shape of the bones and any spurs. [1]
Is an MRI always necessary?
It helps check for soft tissue damage like labral tears. [1]
What is activity modification?
Changing how you move or exercise to avoid pain. [1]
Can FAI cause stiffness in the morning?
Yes, joint stiffness is a common symptom. [1]
Is FAI more common in men or women?
Cam is more common in men; pincer in women. [1]
Can FAI cause clicking in the hip?
Yes, a clicking or catching sensation can occur. [1]
What is the femur?
The thigh bone. [1]
What is the acetabulum?
The hip socket. [1]
How long is recovery after FAI surgery?
It depends on the individual, but often several months. [1]
Can FAI cause buttock pain?
Yes, pain can radiate to the buttocks. [1]
Is FAI a common condition?
It is a well-recognized cause of hip pain in active adults. [1]
What is the L-shape test?
A diagnostic maneuver used during a physical exam. [1]
Can FAI lead to a hip replacement?
If it causes severe arthritis, a replacement may eventually be needed. [1]
Are there non-prescription treatments?
Yes, rest and over-the-counter NSAIDs. [1]
What is minimally invasive surgery?
Surgery done through small incisions with a camera. [1]
Can FAI be diagnosed with a CT scan?
Yes, it provides detailed 3D views of the bone. [1]
Is groin pain always FAI?
No, but it is a primary symptom of the condition. [1]
Does FAI get worse with age?
Symptoms can progress as cartilage wears down. [1]
Can FAI cause thigh pain?
Yes, pain often spreads to the thighs. [1]
What is cartilage?
The smooth tissue that cushions joints. [1]
Is FAI hereditary?
Many people are born with the bone shapes that cause it. [1]
Can I walk with FAI?
Yes, but it may be painful or cause a limp. [1]
What is a bone spur?
An extra growth of bone on a joint. [1]
Should I see a doctor for hip pain?
Yes, if it lasts more than a week or two. [1]
Further Reading
American Academy of Orthopaedic Surgeons (OrthoInfo). Femoroacetabular Impingement. Last reviewed April 2024.
Related Reading
Hip X-Ray: What It Shows, Views Taken and What to Expect explains the X-ray views used to check the hip joint.
References
Cleveland Clinic. Hip Impingement (Femoroacetabular Impingement or FAI): Types. Cleveland Clinic. Last updated June 19, 2025. https://my.clevelandclinic.org/health/diseases/hip-impingement-femoroacetabular-impingement
Griffin DR, Dickenson EJ, Wall PDH, et al. Hip arthroscopy versus best conservative care for the treatment of femoroacetabular impingement syndrome (UK FASHIoN): a multicentre randomised controlled trial. Lancet. 2018;391(10136):2225-2235. PMID 29893223. https://doi.org/10.1016/S0140-6736(18)31202-9
Gatz M, Driessen A, Eschweiler J, et al. Arthroscopic surgery versus physiotherapy for femoroacetabular impingement: a meta-analysis study. Eur J Orthop Surg Traumatol. 2020;30(7):1151-1162. PMID 32382825. https://doi.org/10.1007/s00590-020-02675-6
Mascarenhas VV, Rego P, Dantas P, et al. Imaging prevalence of femoroacetabular impingement in symptomatic patients, athletes, and asymptomatic individuals: A systematic review. Eur J Radiol. 2016;85(1):73-95. PMID 26724652. https://doi.org/10.1016/j.ejrad.2015.10.016
Disclaimer
This information is for educational purposes only and does not constitute medical advice. Always seek the guidance of a qualified healthcare provider with any questions regarding a medical condition.
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