Magnetic resonance imaging of occult scaphoid fractures.

Occult fractures of the scaphoid bone occur frequently and may lead to nonunions. In a prospective blind study, we performed magnetic resonance imaging (MRI) examinations on 32 patients who had sustained a wrist injury and in whom a scaphoid fracture was clinically suspected, but could not be confirmed on the original set of two routine and four scaphoid view radiographs. The MRI examinations were performed an average time of 2.8 days after the trauma. This prospective study proved that MRI is able to diagnose occult scaphoid fractures without delay and without the use of radioactive diagnostic means. Sensitivity and specificity of MRI were 100%. This conventional method could save $7,200 (US) per 100,000 inhabitants in providing an immediate and correct diagnosis and avoiding unnecessary cast immobilization. Additional injuries that may be misdiagnosed by conventional radiographs are also detected with a specificity and sensitivity of 100%.