Bone marrow edema is excess fluid inside the bone marrow, usually a sign of injury, stress, infection, inflammation, or a healing process within the bone.
It often causes deep, aching bone or joint pain that is worse with weight-bearing and may not improve with rest, sometimes with swelling around the joint.
Imaging shows where in the bone the edema is and helps tell the cause apart — stress injury, joint inflammation, recent fracture, avascular necrosis, or infection.
MRI is the test that shows bone marrow edema clearly; X-rays may be normal in the early stages.
Management depends on the cause — rest and offloading for stress injuries, treatment of joint inflammation, antibiotics for infection, or specialist follow-up for AVN.
This entry explains the finding. The next step is having a radiologist interpret your specific scan, not a general definition.
