Fracture of the trapezial ridge.

The trapezial ridge is a longitudinal projection of bone on the palmar surface of the trapezium and serves as an attachment for a portion of the transverse carpal ligament. It can be fractured from a fall onto the outstretched palm. Presented here is a case report of a young woman who sustained a fracture of the trapezial ridge. Point tenderness was a key initial symptom. Standard anteroposterior, lateral, and oblique roentgenograms did not demonstrate the fracture, and the diagnosis was repeatedly missed. The carpal tunnel view was obtained seven weeks after the original injury and showed a nondisplaced fracture through the trapezial ridge. Cast immobilization initiated at that time was not successful in obtaining fracture union. The delay in diagnosis and subsequent nonunion resulted in chronic discomfort and weakness of pinch and grasp. Careful clinical examination for point tenderness over the palmar surface of the trapezium and proper roentgenographic analysis should minimize delays in diagnosis and treatment of this fracture.