Hydroxyapatite Deposition Disease: A Comprehensive Review of Pathogenesis, Radiological Findings, and Treatment Strategies

Hydroxyapatite deposition disease (HADD) represents a multifaceted condition characterized by the accumulation of hydroxyapatite crystals in soft tissues, leading to subsequent inflammation and discomfort. The intricate etiology of HADD is the subject of this comprehensive review, which encompasses an in-depth analysis of the four proposed pathogenic mechanisms and a deliberation on the predisposing factors that instigate the development of this disease. In order to provide a thorough understanding of the disease’s progression, this manuscript delineates the stages of HADD—those preceding calcification, occurring during calcification, and following calcification—in meticulous detail. This chronology forms the basis of a complete portrayal of the evolution of HADD. Moreover, this review encompasses an examination of the radiological findings associated with HADD, furnishing an extensive discourse on imaging characteristics. The potential of HADD to mimic other diseases, thereby posing diagnostic challenges, is also articulated. The discourse continues with an investigation of HADD’s differential diagnosis. This section furnishes a robust framework for distinguishing HADD from other conditions based on imaging results. To enrich the understanding of this diagnostic process, case studies illustrating real-world applications are provided. An overview of treatment modalities for HADD, including both conservative and interventional approaches, forms the concluding discussion. The pivotal role of imaging specialists in the diagnosis and management of HADD is emphasized, highlighting their vital contribution to image-guided procedures and disease monitoring.