Ollier Disease: Pathogenesis, Diagnosis, and Management.

Ollier disease (Spranger type I) is a rare bone disease that is characterized by multiple enchondromatosis with a typical asymmetrical distribution and confined to the appendicular skeleton. The pathogenesis of enchondromatosis is not clearly understood. Recently, heterozygous mutations of PTHR1, IDH1 (most common), and/or IDH2 genes have been suggested by various authors as genetic aberrations. Genomic copy number alterations and mutations controlling many vital pathways are responsible for the pathogenesis of Ollier disease. A comprehensive description of all genetic events in Ollier disease is presented in this article. Clinically, Ollier disease has a wide variety of presentations. This article describes the plethora of clinical features, both common and rare, associated with Ollier disease. Multiple enchondromas are most commonly seen in phalanges and metacarpals. Radiologically, Ollier disease presents with asymmetrical osteolytic lesions with well-defined, sclerotic margins. In this article, various radiological features of Ollier disease, including radiographs, computed tomography, and magnetic resonance imaging, are also discussed. Gross pathology, cytological, and histological features of both Ollier disease and its malignant transformation are outlined. Although treatment is conservative in most cases, different possible treatment options for difficult cases are discussed. In the literature, there is a paucity of data about the disease, including diagnosis, management, prognostication, and rehabilitation, necessitating a comprehensive review to further define all of the possible domains related to this disease.