An Extremely Rare Case of Ollier Disease With Calvarial Involvement.

First described by Ollier in 1899, Ollier disease is a rare, nonhereditary skeletal condition characterized by multiple enchondromas. Enchondromatosis can present bilaterally, often with a predominant side, and may manifest as monomelic or hemiskeletal involvement. Significant clinical challenges in Ollier disease include progressive limb shortening, angular deformities, and an elevated risk of pathologic fractures. In adult patients, malignant transformation is a potential concern. Calvarial involvement in Ollier disease is exceedingly rare, with only a few documented cases. Most reported instances of calvarial involvement pertain to the skull base rather than the calvarial bones. Herein, we present a case of Ollier disease with multifocal enchondromas, including involvement of the calvarium, identified through whole-body bone scintigraphy.