Case discussion
01Clinical context
A patient presented after a fall with elbow pain and swelling. Non-contrast multiplanar MRI of the right elbow was performed to assess for occult injury.
02Key imaging findings
There is a moderate elbow joint effusion with haemorrhagic characteristics (haemarthrosis) and a subtle posterior capsular disruption. Within the posterior joint recess, deep to the distal triceps tendon, a lobulated, somewhat infiltrative-appearing intra-articular synovial/soft-tissue abnormality is seen, isointense to mildly hyperintense on T1 and fluid-sensitive sequences. In the acute post-traumatic setting this is favoured to represent focal haemorrhagic synovial change/blood products, though an underlying synovial proliferative lesion cannot be confidently excluded on this non-contrast study. No acute fracture, marrow oedema, dislocation, or high-grade collateral ligament or tendon injury.
03Teaching point
Traumatic haemarthrosis can harbour a lobulated intra-articular mass that mimics — or masks — a true synovial proliferative process. On a non-contrast study, blood products and synovial lesions overlap in signal, so restraint is warranted: favour the benign post-traumatic explanation but recommend interval follow-up (or contrast-enhanced MRI) to ensure resolution and exclude an underlying lesion. Absence of fracture does not equal absence of significant injury — capsular disruption and hemarthrosis point to meaningful trauma.
Shown for education. De-identified — no identifiable patient data. A radiology report is a specialist opinion and must be read with the full clinical context by the treating physician.