Multiple Hereditary Exostoses instigating a popliteal pseudoaneurysm in a young Middle Eastern male: A case report and literature review

Introduction and importance: Multiple Hereditary Exostoses is a rare autosomal dominant bone disorder that predominantly affects males at an incidence of (1:50,000 to 1:100,000) in Western populations. The etiology is owed to mutations in the EXT gene group, specifically EXT1 and EXT2 which cause the formation of Osteochondromas. Diagnosis is typically established in childhood. Nevertheless, vascular complications are extremely rare while being potentially fatal. Therefore, timely diagnosis and treatment are vital for such patients. Case presentation: We present the case of a 37 -year -old Middle Eastern male with Multiple Hereditary Exostoses who experienced sudden-onset left lower limb pain persisting for a month prior to admission. It was associated with coldness and paresthesia of the ipsilateral lower limb. The presurgical radiological workup uncovered a popliteal pseudoaneurysm subsequent to Multiple Hereditary Exostoses. Clinical discussion: Through open surgery, the vascular perfusion was successfully restored, and a subsequent supra- to infra-geniculate popliteal artery anastomosis via saphenous vein grafting was done. Furthermore, the Osteochondroma was utterly resected to limit recurrence of another vascular injury. The following histopathological analysis confirmed the diagnosis of an Osteochondroma as a result of MHE. Conclusion: Multiple Hereditary Exostoses is a rare occurrence leading to pseudoaneurysms. This event underscores the need for further documentation to aid in establishing a prompt diagnosis and carrying out suitable interventions. Considering this pathology in a multidisciplinary approach ensures proper treatment. Following a comprehensive literature review, our case stands as the first case in the published literature from our country which emphasizes its value and rarity.