An Isolated Pure Dislocation of Fifth Carpometacarpal Joint: Case Report and Review of Literature

INTRODUCTION: Isolated pure dislocation of the fifth carpometacarpal (CMC) joint is a very rare injury and classified depending on displacement of the metacarpal base. This rare injury is often difficult to recognize and is liable to be overlooked. The purpose of this case report is to present a patient with an isolated dislocation of the fifth CMC joint that was satisfactorily treated with closed reduction and ulnar gutter pop slab. CASE REPORT: A 21-year-old male presented with severe pain on the right carpus following a fall with injury to right hand. There was a mild swelling at fifth CMC joint region and a bony prominence was felt dorsally, little finger presented an abduction deformity, and there was apparent shortening of the fifth ray. A diagnosis of isolated dislocation of fifth CMC dislocation was made based on radiographs. Immediate closed reduction was done in emergency room by applying longitudinal traction and direct pressure on metacarpal base dorsally, reduction was stable and confirmed by postreduction radiographs. CONCLUSION: Isolated pure dislocation of the fifth CMC joint is very rare injury and is prone to be missed in emergency room and particular attention should be made to diagnose it in polytrauma patients.