Total Volar Extrusion of the Lunate and Scaphoid Proximal Pole With Concurrent Scapholunate Dissociation

Abstract

This article describes a case of a 24-year-old man with a total volar extrusion of the lunate and scaphoid proximal pole with concurrent scapholunate dissociation. The viability of the lunate and the proximal pole of the scaphoid are at high risk in this type of injury. Scaphoid nonunion, avascular necrosis of the lunate and proximal pole of the scaphoid, and carpal instability are inevitable unless the blood supply is restored. Thus, proximal row carpectomy at injury may be an acceptable option to avoid these complications and late sequelae, including chronic wrist pain and dysfunction. However, the authors attempted accurate reduction of the extruded bones and internal fixation.Final radiographs and magnetic resonance imaging 12 years postoperatively showed healing without avascular necrosis. Carpal indices involving the scapholunate angle, radiolunate angle, and carpal height ratio were similar in both wrists without evidence of carpal instability or collapse. Range of motion and grip power were 75% and 76%, respectively, compared with those of the uninjured wrist. Clinical scores showed good results, and the patient reported no pain during activities of daily living and was satisfied with his surgical results. Open reduction and internal fixation can be a viable option in this rare pattern of injury.