HSS Ultrasound of the Month Case 124

Clinical History 55-year-old male with sensation of a tiny nodule along the dorsal aspect of the big toe with intermittent swelling.

Diagnostic ultrasound of the toe was requested to evaluate for a ganglion cyst.

Ultrasound of the Month – Case 123

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Ultrasound of the Month – Case 123

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Ultrasound of the Month – Case 123

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Diagnosis: Intra-articular Loose Body of the First MTP Joint Loose bodies are free fragments, usually cartilaginous, calcified, or osseous, that are inside the joint. A foreign body can also be a loose body in the setting of prior penetrating injury or surgery.

If the loose body irritates that joint, it can lead to synovitis and present with swelling of the joint. If the loose body is in an area close to the skin, it can also present as a palpable abnormality, as in the current patient.

Ultrasound is a good imaging modality for identifying synovitis, and if the loose body is palpable to the patient, the source of the palpable abnormality can be identified on ultrasound.

Other sources of a palpable nodule about a joint include ganglion cysts, soft tissue neoplasms, osteophytes, vascular lesions such as thrombophlebitis or pseudoaneurysms, and proud surgical screws/implants.

Loose bodies that are deep inside a joint may be more easily diagnosed on MRI.

Ultrasound of the Month – Case 123

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