Young athletes commonly develop bone marrow oedema in the joints of the lower spine, according to new research.
This damage most frequently occurs in the posterior lower ilium, or the lowest part of the spine where it connects to the pelvis, followed by the anterior upper sacrum.
The findings, presented at the recent ACR/ARHP Annual Meeting in San Diego, could help in the diagnosis of axial spondyloarthropathy (axSpA), a disease where bone marrow oedema and structural lesions in the sacroiliac joints are common.
AxSpA is an inflammatory disease with low back pain as its main symptom. Spondyloarthritis (SpA) can also affect the arm and leg joints, and organs such as the skin, eyes or intestines. Inflammation often affects the sites where ligaments and tendons attach to bones.
It’s thought that a better understanding of how bone marrow oedema develops in healthy, active individuals may improve evaluation of magnetic resonance imaging (MRI) of the same joints in individuals with early axSpA.
Researchers in Denmark examined MRI scans for runners and ice hockey players to determine the frequency of bone marrow oedema and its distribution across eight regions of the sacroiliac joints.
The mean number of sacroiliac joint quadrants showing bone marrow oedema in the runners was 3.1 before and after running, and 3.6 in the hockey players. In both the recreational and professional athletes, bone marrow oedema was found in three to four sacroiliac joint quadrants on average.
“There is an ongoing debate about what constitutes a ‘positive sacroiliac joint MRI’ in patients with axial SpA,” commented Dr Ulrich Weber, a researcher at King Christian 10th Hospital for Rheumatic Diseases in Graasten, Denmark, and a lead author of the study. The most common definition is bone marrow oedema (BME) on fluid-sensitive MRI sequences. “However, we lack a data-driven threshold or ‘reference range,’ which reliably discriminates patients with SpA from the BME ‘background noise’ in healthy individuals, or from BME seen in patients with mechanical back pain.”
The presence of solely low-grade bone marrow oedema, especially clustered in the posterior lower ilium or anterior upper sacrum, may not be sufficient to confirm axial SpA in these patients, Dr Weber explained.
“This study’s results may enhance management of SpA patients by allocating treatment resources more specifically, especially if a rheumatologist is considering effective, but expensive, biological therapy,” he concluded.