Post-traumatic cyst-like lesion of cortical bone in children.

Post-traumatic cyst-like lesions are an infrequent complication of fractures in children. To our knowledge, no more than 30 cases have been reported in the English-language literature. They most commonly affect the distal radius following a greenstick or torus fracture. These cortical defects are often asymptomatic, non-expansile, and typically resolve spontaneously in 1-3 years. They appear proximal to the compression site and are usually identified 2-4 months after a minor fracture. These lesions have a distinct appearance on magnetic resonance imaging (MRI), with intralesional fatty marrow, which may help to differentiate it from other bone lesions. We review the literature and present 3 more cases studied with plain radiographs, computed tomography (CT), and MRI. Post-traumatic cyst-like lesions require no treatment, and therefore recognition of its typical features is crucial to prevent unnecessary invasive procedures.