Hip MRI Report Explained: What Your Results Mean

Key Takeaways

Hip MRI reports commonly describe findings related to the labrum, cartilage, tendons, bursae, and bone marrow.
A labral tear is one of the most frequently reported hip MRI findings — it means the ring of cartilage surrounding your hip socket has a tear or damage.
Many hip MRI findings, including small labral tears and mild bursitis, are common even in people without symptoms and do not always require surgery.
Your orthopedic surgeon or referring doctor interprets your MRI results alongside your symptoms and physical exam to determine the best treatment plan.

A hip MRI uses strong magnetic fields and radio waves to create detailed images of the bones, cartilage, muscles, tendons, and ligaments in and around your hip joint. The scan typically takes 30–45 minutes, and you will need to lie still inside the MRI machine during the procedure.

Some hip MRIs are performed with an injection of contrast dye (called an MR arthrogram), where a small amount of gadolinium-based contrast is injected directly into the hip joint before the scan. According to RadiologyInfo.org, an MR arthrogram provides better visualization of the labrum and cartilage surfaces, making it the preferred technique when a labral tear is suspected.

If you are unfamiliar with MRI reports in general, our guide to reading MRI reports covers the basic structure and common terminology.

Labral Tears

The labrum is a ring of tough fibrocartilage that lines the rim of your hip socket (acetabulum). It deepens the socket, helps stabilize the joint, and creates a seal that keeps fluid inside. A labral tear means this ring has been partially or fully torn.

What Your Report May Say

"Anterior superior labral tear" — A tear in the front-top portion of the labrum, which is the most common location.
"Labral fraying" or "labral degeneration" — Wear and thinning of the labrum, often age-related.
"Paralabral cyst" — A fluid-filled cyst that forms adjacent to a labral tear, caused by joint fluid leaking through the torn labrum.
"Labral detachment" — The labrum has separated from the bone at its attachment point.

Research published by the Radiological Society of North America (RSNA) shows that labral tears are found in up to 69% of hip MRI scans in people with hip or groin pain. However, studies also reveal that labral changes appear in 56–74% of asymptomatic individuals, so a finding on MRI does not automatically mean it is the source of your pain.

Cartilage and Bone Findings

Articular Cartilage Damage

The articular cartilage is the smooth, slippery coating on the surfaces of the femoral head (ball) and acetabulum (socket). Your report may describe:

"Chondral thinning" or "cartilage loss" — Wearing down of the cartilage surface, often a sign of early osteoarthritis.
"Chondral defect" or "osteochondral lesion" — A localized area where cartilage (and sometimes underlying bone) is damaged or missing.
"Joint space narrowing" — Reduced space between the ball and socket, suggesting cartilage loss.

Bone Marrow Edema

Bone marrow edema appears as a bright area on fluid-sensitive MRI sequences. It indicates increased fluid within the bone and can result from stress reactions, early arthritis, fractures, or other conditions. The Mayo Clinic notes that bone marrow edema in the hip can be an early sign of avascular necrosis before structural changes become visible.

Avascular Necrosis (AVN)

Avascular necrosis (also called osteonecrosis) occurs when the blood supply to the femoral head is disrupted, causing bone tissue to die. On MRI, it typically appears as a crescent-shaped area of abnormal signal in the femoral head. Risk factors include long-term corticosteroid use, excessive alcohol consumption, and prior hip trauma. Early detection on MRI is critical because treatment options are more effective before the femoral head collapses.

Soft Tissue Findings

Bursitis

Bursae are small fluid-filled sacs that cushion the bones, tendons, and muscles around your hip. Inflammation of these sacs — called bursitis — appears on MRI as fluid accumulation. Common types include:

Trochanteric bursitis — Inflammation on the outside of the hip, the most common type.
Iliopsoas bursitis — Inflammation of the bursa near the front of the hip.

Tendon Problems

Your hip MRI may also describe tendon abnormalities:

"Tendinopathy" or "tendinosis" — Degeneration of a tendon, commonly affecting the gluteus medius or hamstring tendons.
"Partial-thickness tear" or "full-thickness tear" — A tear in a tendon. Gluteus medius tears are sometimes called "rotator cuff tears of the hip" because they cause similar lateral hip pain.

If you have had a shoulder MRI, you may notice similar terminology used for rotator cuff findings.

Femoroacetabular Impingement (FAI)

FAI is a condition where extra bone grows along the femoral head or acetabular rim, causing the bones to rub against each other during movement. Your report may describe:

"Cam morphology" — A bump on the femoral head (ball) that reduces its roundness.
"Pincer morphology" — Extra bone extending over the rim of the acetabulum (socket).
"Combined cam and pincer" — Both types present simultaneously.

FAI is a common structural finding, affecting approximately 10–15% of the general population according to the American College of Radiology (ACR). It is frequently associated with labral tears and cartilage damage, but many people with FAI morphology on imaging have no symptoms at all.

Frequently Asked Questions

Does a labral tear always need surgery?

No. Many labral tears, especially small ones without significant symptoms, can be managed with physical therapy, anti-inflammatory medications, and activity modification. Surgery (hip arthroscopy) is typically considered when conservative treatment fails after 3–6 months or when there is significant mechanical catching or locking.

What does "mild hip joint effusion" mean?

A joint effusion is a collection of fluid inside the hip joint. A mild effusion is common and often benign — it can result from inflammation, overuse, or even be a normal variant. Your doctor will consider this finding alongside your symptoms and other imaging results.

How accurate is a hip MRI?

A standard hip MRI has high accuracy for detecting bone and soft tissue abnormalities. For labral tears specifically, MR arthrography (with contrast injection) has a sensitivity of approximately 90–95%, making it the gold standard. A standard MRI without contrast detects labral tears with about 70–80% sensitivity.

Disclaimer: This article is for educational purposes only and does not constitute medical advice. Always consult with a qualified healthcare professional for diagnosis and treatment decisions.