The elusive bipartite scaphoid: a rare congenital variant or misdiagnosed pseudoarthrosis? A proposal for novel radiological criteria

Abstract

Variations in the development of carpal bones are uncommon, with the scaphoid bone typically forming from the fusion of the os centrale carpi and the radial chondrification center during embryogenesis. A bipartite scaphoid is a rare congenital disorder that occurs when these ossification centers fail to fuse, with a prevalence ranging from 0.1% to 0.6% in adult dissection. The differentiation between a bipartite scaphoid and pseudoarthrosis is challenging, complicating accurate diagnosis and evaluation. A 37-year-old male presented with right wrist pain following a minor fall. Physical examination revealed no visible deformity or swelling but restricted range of motion due to pain. Radiographic imaging identified a bipartite scaphoid with two distinct, similar-sized ossification centers, regular oval shape, smooth margins, and consistent cortical-to-medullary ratio, with no acute fractures or dislocations. The patient was treated conservatively with non-steroidal anti-inflammatory drugs and immobilization. Upon follow-up, the patient reported complete pain resolution and full range of motion in the wrist. This case emphasizes the unusual occurrence of a bipartite scaphoid bone in a patient experiencing wrist pain after a minor injury. It highlights the challenge of differentiating between a congenital bipartite scaphoid and post-traumatic pseudoarthrosis, underscoring the importance of considering this uncommon developmental variant when diagnosing and treating wrist pain.