Mechanical stress and bone marrow edema
Bone marrow edema (BME) is a condition that involves the accumulation of interstitial fluid within the bone marrow. BME can derive from injury to the bones and it is often distinguished by type - traumatic BME, nontraumatic BME, reactive BME or mechanical BME. In order to determine a diagnosis for non radiographic axial spondyloarthritis, an MRI needs to be performed on the sacroiliac joints. However, recent findings depict that these changes may also be seen in individuals without non radiographic axial spondyloarthritis, suggesting that mechanical stress on the joints in BME plays a vital role. These findings suggest that sacroiliac joint bone marrow edema cannot be diagnosed with non radiographic axial spondyloarthritis. As a result, further efforts need to be made in order to better understand disease-specific MRI results.