Hip osteonecrosis (avascular necrosis of the femoral head)

Practical guidance for hip pain, stiffness, and next steps

Avascular necrosis of the femoral head (also called hip osteonecrosis) happens when blood supply to the “ball” of your hip joint reduces. As a result, bone tissue can weaken and, in some cases, the femoral head may collapse over time. This can lead to persistent hip or groin pain and reduced function.

If your symptoms look like general hip pain or hip and groin pain, a clear diagnosis matters because early-stage avascular necrosis can look similar to other hip problems.

For a plain-English overview of osteonecrosis, see this non-commercial health reference: MedlinePlus (NIH): Osteonecrosis.

What causes avascular necrosis of the femoral head?

Avascular necrosis can be traumatic or non-traumatic:

• Trauma (for example, a hip dislocation or fracture) can disrupt blood flow to the femoral head.
• Corticosteroid use and high alcohol intake are common non-traumatic risk factors reported in clinical reviews.
• Blood flow and clotting issues may contribute in some people (for example, sickle cell disease and other medical conditions).

Not everyone has an obvious trigger. Therefore, your clinician will usually ask about medication history, prior injury, alcohol intake, and other health conditions.

Symptoms

Early avascular necrosis may cause little to no pain. As it progresses, symptoms often include:

• Deep groin pain, hip pain, or aching in the buttock
• Pain that worsens with walking, stairs, or standing for longer periods
• Stiffness and reduced hip range of motion
• Limping and reduced tolerance to sport or work tasks

If your pain mainly sits deep in the groin with twisting or hip flexion, your clinician may also check for overlapping problems such as femoroacetabular impingement syndrome (FAIS).

People also ask: can avascular necrosis be missed on an X-ray?

Yes. Early-stage avascular necrosis may not show on a standard X-ray. For that reason, clinicians often use MRI when symptoms and risk factors suggest osteonecrosis, even if initial X-rays look normal.

How is avascular necrosis diagnosed?

Diagnosis usually combines clinical assessment with imaging. MRI is commonly used to detect early changes in the femoral head and can also help stage the condition and guide treatment decisions. In later stages, X-ray and CT can show structural change or collapse.

If hip arthritis becomes part of the picture, you may also see information referenced alongside hip replacement options. Your treating team will match recommendations to your stage, symptoms, and goals.

Treatment options

Treatment depends on the stage of the condition and whether the femoral head has started to collapse. While exercise and physiotherapy can help with strength, gait, and load management, many people with avascular necrosis still need medical or surgical input to address the underlying bone changes.

Common early management goals

• Reduce painful load through the hip (often with activity modification and, at times, crutches)
• Maintain hip mobility and muscle capacity without flaring symptoms
• Support safe work, daily activity, and graded return to exercise where appropriate

Medical and surgical options (guided by your doctor)

• Core decompression is a commonly used joint-preserving procedure for earlier stages. Some approaches combine core decompression with biological or structural augmentation.
• Joint-preserving surgery (for selected cases) may aim to delay progression and maintain the femoral head for as long as practical.
• Total hip replacement may be recommended when collapse or advanced joint damage leads to persistent pain and reduced function.

Because timing matters, it’s worth discussing your scan results early with your GP and, when needed, an orthopaedic surgeon. Your physiotherapist can also help you plan safe activity levels and improve strength and walking mechanics while you weigh up treatment options.

What to do next

• If you have persistent groin or hip pain, book an assessment to clarify the most likely source.
• If avascular necrosis is suspected, ask whether MRI is appropriate for your stage and symptoms.
• While you wait for results, reduce flare-ups by limiting high-impact loading and using pacing strategies.

Rehabilitation support tools

Some people use balance and stability tools to support lower-limb control and gait retraining during rehab. Your physiotherapist can advise what suits your stage and symptoms.

References

1. Hines JT, Jo WL, Cui Q, et al. Osteonecrosis of the femoral head: an updated review of ARCO on pathogenesis, staging and treatment. J Korean Med Sci. 2021;36:e177. https://pmc.ncbi.nlm.nih.gov/articles/PMC8216992/
2. Ko YS, Kim HJ. Updating Osteonecrosis of the Femoral Head. Hip Pelvis. 2023;35(3):147-158. https://pmc.ncbi.nlm.nih.gov/articles/PMC10505838/
3. Qi T, et al. Hip joint-preserving strategies for treating osteonecrosis of the femoral head. 2025. https://pmc.ncbi.nlm.nih.gov/articles/PMC11968294/
4. Yue J, et al. Reliability and repeatability of 2021 ARCO classification for early-stage ONFH. BMC Musculoskelet Disord. 2023. https://pubmed.ncbi.nlm.nih.gov/37291529/
5. Konarski W, et al. Effectiveness of different types of core decompression in osteonecrosis of the femoral head. 2025. https://www.mdpi.com/2076-3271/13/4/258