Deep Groin Pain and a Stiff Hip: Avascular Necrosis Warning Signs

You noticed it first after a long walk: a deep, dull ache in the front of your hip, right in the groin. You figured you had pulled something. But weeks later it is still there, and now it bothers you when you sit, when you bend to put on your socks, and sometimes even when you are lying still.

Most hip and groin pain comes from muscles, tendons or wear in the joint. Once in a while, though, the cause is a problem with the blood supply to the bone itself. It is called avascular necrosis, and it is worth knowing about, because catching it early can change what treatment options are open to you.

What is avascular necrosis of the hip?

Your hip is a ball and socket joint. The ball is the top of your thigh bone, called the femoral head. Like all living bone, it needs a steady blood supply.

Avascular necrosis (AVN), also called osteonecrosis, happens when the blood supply to the femoral head is disrupted. Without enough blood, parts of the bone can break down and change shape. Over time the ball can flatten or collapse, which can lead to stiffness and arthritis in the hip.

The tricky part is that AVN often starts quietly. Doctors who study it describe the early signs as minimal and nonspecific until the disease is more advanced. Early on, a plain X-ray can look normal even when the hip hurts.

Who is more at risk?

Many cases have no clear cause. Still, some things are linked to a higher risk:

• Steroid medication: long-term or high-dose corticosteroids, such as those used for asthma, cancer, lupus or after an organ transplant
• Heavy alcohol use over a long period
• Sickle cell disease and some other blood and metabolic conditions, such as Gaucher disease
• Hip injury: a dislocation or fracture that damages blood vessels
• Other conditions and treatments: lupus, Crohn's disease, radiotherapy, and decompression sickness in divers

The American Academy of Orthopaedic Surgeons notes that AVN of the hip is more common between the ages of 40 and 65, and in men more than women. In many cases, both hips are affected.

Warning signs to know

AVN can look a lot like ordinary hip arthritis or a groin strain. These are the signs that make us look more closely:

• A deep ache in the groin, buttock or side of the hip, sometimes spreading down the thigh toward the knee
• Pain at first only when you put weight on the leg, then later pain at rest
• A limp, or pain when walking
• Pain when sitting, bending forward or squatting
• Growing stiffness, so socks, shoes and cutting your toenails get harder
• Hip pain that is worse than expected for your age or activity level
• Any of the above if you take steroids, drink heavily, have sickle cell disease or have had a hip injury

When to see your doctor

AVN is not usually a 911 emergency. But it should not be left to "wait and see" either. Book an appointment with your family doctor soon if:

• You have groin or hip pain that has lasted more than a few weeks and is not settling
• Your hip pain is now there at rest or at night
• You have hip pain and one of the risk factors listed above
• You have been told you have hip arthritis, but you are younger than expected or it is getting worse quickly

Your doctor may order an X-ray first. Because early AVN can be missed on X-ray, an MRI is often the next step. MRI is considered the best test for spotting early changes, and it can also pick up early disease in the other hip. From there, your doctor may refer you to an orthopaedic surgeon.

If you suddenly cannot put weight on your leg after a fall or injury, go to the emergency department.

Why your physiotherapist asks about this

When you come to Vaughan Physiotherapy Clinic with hip or groin pain, your physio will ask questions that might seem unrelated: Do you take steroid medication? How much alcohol do you drink? Do you have any blood conditions? Have you had a hip injury?

These questions help us sort out what kind of hip pain you have. We also look at how your pain behaves. Pain from a strained muscle usually changes with certain movements and settles with rest. Deep groin pain that keeps building, comes on at rest, or does not match what we find on testing is a reason to pause.

When something does not fit a normal muscle or joint pattern, we stop and refer. That means writing to or calling your family doctor, explaining what we found, and suggesting imaging be considered. We would much rather send you for a check that turns out normal than miss something that matters.

What physiotherapy can and can't do

Physiotherapy cannot restore blood supply to the bone or reverse AVN. Medical and surgical care, guided by your doctor and orthopaedic surgeon, is the main treatment.

What physio can do is support you alongside that care. For early AVN managed without surgery, hospital physiotherapy teams describe a role in:

• Teaching safe use of crutches or a cane to take load off the hip, if your surgeon recommends it
• Showing you which positions and activities ease or aggravate your symptoms
• Keeping the muscles around your hip, leg and trunk strong
• Suggesting lower-load exercise such as pool work or a stationary bike

If you need surgery, such as a hip replacement, physiotherapy is a key part of recovery afterward.

Key takeaways

• AVN happens when the ball of the hip loses part of its blood supply.
• Deep groin pain, pain at rest, and growing stiffness are signs worth checking.
• Steroid use, heavy alcohol use, sickle cell disease and hip injury raise the risk.
• Early AVN may not show on X-ray. MRI is the preferred test.
• Physio screens for AVN and refers. It supports recovery but does not treat the bone loss itself.

Related reading: You may also find our guides to hip joint stiffness and labral tears of the hip helpful.

If your hip pain has been hanging around, our team can help you figure out what is going on and, when needed, get you to the right doctor. You can read more about how we help with hip arthritis on our hip osteoarthritis page.

Call: 905-669-1221

Visit: 398 Steeles Ave W #201, Thornhill, ON

Book online: vaughanphysiotherapy.com

Sources

American Academy of Orthopaedic Surgeons. (n.d.). Osteonecrosis of the hip. OrthoInfo. https://orthoinfo.org/en/diseases--conditions/osteonecrosis-of-the-hip/

Choi, H. R., Steinberg, M. E., & Cheng, E. Y. (2015). Osteonecrosis of the femoral head: Diagnosis and classification systems. Current Reviews in Musculoskeletal Medicine, 8(3), 210 to 220. https://doi.org/10.1007/s12178-015-9278-7

Royal National Orthopaedic Hospital NHS Trust. (2025). A patient's guide to avascular necrosis (AVN). https://www.rnoh.nhs.uk/patients-and-visitors/patient-information-guides/patients-guide-avascular-necrosis-avn

This article is for general information and isn't medical advice. If you have any of the warning signs above, call 911 or contact your doctor right away.