High-energy Trauma Precipitating Intramedullary Cavernous Malformation Hemorrhage - A Possible Underreported Mechanism.

Cavernous malformations are uncommon vascular lesions with an estimated prevalence of 0.5% in the general population. Intramedullary cavernous malformations (ICM) represent a rare subset of lesions, which account for approximately 5% of all cavernous malformations. The annual risk of hemorrhage in ICMs has been reported to range from 1.4 to 6.8%. Most patients are diagnosed with neurological dysfunction secondary to ICM hemorrhage and little is known about the inciting events that lead to hemorrhage. A few studies have suggested that minor and major trauma or even intense exertion may increase the risk of hemorrhage. We report the case of a 62-year-old male who developed progressive neurological deterioration following a motor vehicle accident. During work-up, an ICM was found at T4 and was surgically removed. At his 10-month follow-up, the patient had partially recovered, regaining motor strength in his right lower extremity, but had a persistent decrease in temperature and pinprick sensation on the left side starting at the T6 dermatome. We hypothesize that ICMs can rupture after high-energy impacts, such as the motor vehicle accident in our patient, and mechanical factors, such as trauma and stretching maneuvers, can play a role in the pathogenesis of ICM hemorrhage.