gms | German Medical Science

Objectives/Interrogation: Bipartite carpal scaphoid is a rare congenital anomaly of carpal bones. The scaphoid usually has one ossification center. We present a case of bilateral division of the carpal scaphoid in a 57-year-old man.

Methods: He presented to our outpatient clinic with acute pain and swelling in his right wrist without a history of trauma. Physical examination showed tenderness, heating sense, and mild redness in the dorsum of the entire wrist. The patient had an elevated white blood cell (WBC) count with left shift, an erythrocyte sedimentation rate (ESR) and a C-reactive protein (CRP). A diagnosis of cellulitis was made. Plain radiographs of bilateral wrist were obtained for routine evaluation, and incidentally noted the scaphoid bone composed of two ossicles separated at the waist with smooth margins in his bilateral wrist. He had no previous history of wrist trauma and a normal developmental history. Magnetic resonance imaging (MRI) revealed bilateral bipartite scaphoids with cartilaginous tissue evident between the two ossicles. The symptom resolved after intravenous antibiotic therapy.

Congenital bipartite carpal scaphoid was first described by Gruber in 1877, and Bunnel and Boys proposed the criteria of bipartite scaphoid in 1970. Several factors were considered to be supportive of the diagnosis of congenital bipartite scaphoid rather than traumatic non-union in this patient. These included bilateral scaphoid bipartition, clear space between the two components with smooth edges at the joint surfaces, equal size and density of each part, and no history or signs of wrist injury. In this case, there were a few degenerative changes in the articulation between the distal ossicle and the radial styloid. However, several reports suggest that degenerative change developed due to abnormally biomechanics incurred by a bipartite scaphoid. The authors concluded that the case presented is bilateral bipartite carpal scaphoid and the patient discharged without further treatment.

After our first experience, a 51-year-old man with a distal radio-ulnar fracture presented to the emergency department and unrecognized bilateral scaphoid fracture nonunion was found on radiography. This patient did not fulfill the five established criteria.

Results and Conclusions: Differential diagnosis of bipartite carpal scaphoid and non-union is difficult, but knowledge of congenital bipartite scaphoid is important to avoid unnecessary treatment.