Carpal Boss: A Case Series of a Radiological Enigma in Dorsal Wrist Pathology

Carpal boss, a relatively rare and often underdiagnosed condition, is characterized by a bony protuberance at the dorsal aspect of the carpometacarpal (CMC) joint. It is commonly misdiagnosed due to its nonspecific clinical presentation, which can mimic other conditions, such as ganglion cysts or fractures. This case series aims to document and analyze the clinical presentations and radiological findings of three patients diagnosed with carpal boss, highlighting the importance of advanced imaging techniques in accurate diagnosis and management. A case series was conducted at Tenet Diagnostics, Bengaluru, Karnataka, involving three patients with dorsal wrist pain and swelling at the CMC joint. All patients underwent clinical evaluation followed by imaging studies using 3T magnetic resonance imaging (MRI) (United Imaging, Shanghai, China) and 32-slice computed tomography (CT) (Siemens Somatom Go; Siemens Healthineers, Munich, Germany). The MRI sequences included T1-weighted and proton density (PD) fat-saturated images, while CT imaging focused on axial and sagittal sections to assess bony structures. All three patients were diagnosed with carpal boss based on imaging findings. MRI revealed hypertrophied bony protuberances at the bases of the second and third metacarpal bones, forming pseudoarthrosis with associated osteoarthritic changes. CT imaging confirmed these findings, providing high-resolution views of the bony abnormalities. Combining MRI and CT was crucial in differentiating carpal boss from other potential diagnoses, such as ganglion cysts or fractures. This case series underscores the importance of advanced imaging modalities, such as MRI and CT, in diagnosing carpal boss. Accurate and early diagnosis can prevent mismanagement and guide appropriate treatment strategies, improving patient outcomes. Increased awareness of carpal boss among clinicians and radiologists is essential for promptly recognizing and managing this condition.