Intraosseous Varix of the Left Tibia Causing Severe Lower Extremity Pain: A Report of a Rare Case.

Varicose veins are venous anomalies of the peripheral venous system that commonly present with lower extremity pain and swelling. Intraosseous varices are a very rare subtype of varicose veins with an atypical presentation and thus pose a significant diagnostic challenge, leading to prolonged patient morbidity. Only a handful of cases have been reported of this rare entity. We report a case of a 73-year-old male with a history of hyperlipidemia who presented with a 4-week history of worsening left lower extremity pain. Initial workup, including labs, radiography, and ultrasound Doppler, ruled out fracture, electrolyte imbalances, deep venous thrombosis, myopathies, and rhabdomyolysis. A subtle tibial shadow on radiography prompted MRI evaluation. It demonstrated a well-defined intramedullary lesion within the tibia exhibiting high signal intensity on T2-weighted sequences, low-to-intermediate signal on T1-weighted images, and avid post-gadolinium enhancement--findings consistent with a prominent tibial intraosseous varix. The patient was initially managed conservatively with compression stockings and daily exercise with minimal relief over the next eight weeks. The patient therefore underwent sclerotherapy of the left tibial varicose vein, leading to significant symptomatic improvement at the four-week follow-up. This case highlights the significance of rare and atypical clinical entities, such as intraosseous varicose veins of long bones, which pose considerable diagnostic challenges due to persistent symptoms and benign initial workup. It also underscores the critical role of advanced imaging like MRI in establishing the diagnosis and helps distinguish it from aggressive osseous lesions. Although a conservative approach may provide some benefit initially, interventional therapies like sclerotherapy should be considered in cases where symptoms persist despite conservative measures.