Pathologic fracture revealing solid aneurysmal bone cyst of the distal radius

Introduction: Aneurysmal Bone Cyst (ABC) is a rare benign and expansive osteolytic bone tumor that can involve all bone. In less than 5% of cases, ABC is located in the hand and the distal radius. A solid variant is an atypical and unusual form of ABC; it is exceptional and represents often a real diagnostic challenge for clinicians. We report an original observation of a solid variant of ABC of the distal radius revealed by a pathologic fracture in 20-year-old Tunisian man. Case report: A 20-year-old patient, with no medical history, was explored for acute and non-traumatic pain of the lower third of the left forearm with the inability to mobilize his left wrist. Somatic examination and radiological investigations concluded to an eccentric lytic lesion, blowing and deforming the distal end of the left radius, with heterogeneous content, surrounded by a border osteocondensation (Lodwick type IA osteolysis), and complicated by a pathologic non-displaced fracture. The patient was operated with the diagnosis of a giant cell tumor. He had a complete curettage with spongy graft, and internal fixation by plates. The histopathological examination concluded to the diagnosis of ABC in its solid form. Conclusion: The solid variant of the ABC is particularly rare, and since its initial description by Sanerkin et al. in 1983, only a few sporadic cases have been reported in the world literature. Distal radius involvement remains exceptional.