(Kiosk 2) An Uncommon Cause of Thigh Pain with Squatting: A Case Report

Case Diagnosis: 32-year-old female with no significant past medical history who presented with medial thigh pain secondary to intravascular venous malformation.

Case Description or Program Description: The patient presented with chronic right medial thigh pain that started six years ago without inciting injury. Patient had previously aggravated her symptoms with squatting and then prolonged standing in the operating room at work as an orthopedic spine physician assistant. A few weeks prior to presentation, her thigh pain once again occurred in the setting of compensating for a sprained right ankle. Pain improves with rest and ice, equivocal relief with ibuprofen and Medrol dose Pak.

Setting: Outpatient Clinic

Assessment/Results: Physical exam was significant for mild pain with deep squatting and tenderness to palpation at right distal vastus medialis oblique muscle with preserved strength, range of motion, and sensation. A bedside ultrasound performed on the right anterior thigh displayed a large defect without evidence of doppler flow concerning for a VMO tear. An MRI of right femur was ordered for further evaluation. MRI did not show a muscle tear, but instead was consistent with intramuscular venous malformation. Patient was referred to vascular interventional radiology for sclerotherapy. An additional MRI Brain was ordered to rule out intracranial vascular malformations.

Discussion (relevance): Intramuscular venous malformations expand with age and hormonal changes, often becoming symptomatic later in life. Exercise can exacerbate the pain associated with intravascular venous malformations. Identifying intramuscular venous malformations is important as they can be associated with other syndromes and coagulopathies requiring further evaluation. MRI is the gold standard for characterization of intramuscular venous malformations. Recurrence after intervention is common, so surveillance is necessary.

Conclusions: Vascular malformations are a rare but potential source of musculoskeletal pain. Bedside ultrasound can detect anatomic abnormalities early which are not seen on x-ray and prompt earlier detection and treatment.