An Unusual Case of Calcific Periarthritis Causing Carpal Tunnel Syndrome and Its Management with Ultrasound-Guided Barbotage.

Hydroxyapatite crystal deposition disease (HADD) is a common disorder resulting from the deposition of calcium hydroxyapatite crystals in various soft tissues, typically in periarticular distribution, including tendons, tendon sheaths, joint capsules, ligaments, bursae, periarticular soft tissues, and occasionally within the joints. The more commonly known subtypes of HADD are calcific tendinopathy and calcific periarthritis. Carpal tunnel syndrome (CTS) can be rarely caused by calcific deposits within the carpal tunnel in the setting of HADD-related calcific periarthritis. Imaging, particularly ultrasound and radiographs, is crucial in distinguishing this entity from the conventional form of CTS that tends to be idiopathic. We describe a rare presentation of CTS secondary to calcific periarthritis in a 45-year-old patient, with imaging demonstrating mass-like calcification within the carpal tunnel, with typical features of those seen with HADD. The patient was treated with ultrasound-guided barbotage, with significant clinical improvement. The case highlights a lesser-known cause of CTS as well as a presentation of HADD, and the role of ultrasound-guided barbotage, a minimally invasive procedure, as a viable first-line management option as an alternative to surgery.