Intraarticular osteoid osteoma of elbow joint associated with synovitis
Presentation
Pain and stiffness of right elbow joint since one year. No trauma. No fever.
Patient Data
MRI OF RIGHT ELBOW JOINT
MRI of right elbow joint shows a well-defined small subcortical lesion in the anterior cortex of medial humeral condyle, which shows central T2 and T1 hypointense signal and a thin rim of PD FS hyperintense signal. Mild surrounding bone marrow edema is noted.
Moderate elbow joint effusion is noted with mild synovial thickening - representing synovitis.
Annotated bone window CT image at the level of the lesion shows a lytic subcortical lesion with central ossification - consistent with osteoid osteoma.
Case Discussion
Intraarticular osteoid osteomas are rare. They mimic inflammatory arthritis clinically with painful restricted movements. These lesions can be missed on plain radiographs.
MRI and CT are complementary in diagnosing the condition, with MRI identifying the lesion and associated intraarticular pathologies.
Associated synovitis is thought to be due to release of cytokines by the intraarticular osteoid osteoma.