Fifty-seven patients with acute cervical spine injuries and associated major neurological deficit were examined within 2 weeks of injury by magnetic resonance (MR) imaging. All patients had abnormal scans, indicating intramedullary lesions. This study was undertaken to determine if the early MR imaging pattern had a prognostic relationship to the eventual neurological outcome. Three different MR imaging patterns were observed in these patients: 21 patients had patterns characteristic of intramedullary hematoma (Group 1); 17 had intramedullary edema over more than one spinal segment, but no hemorrhage (Group 2); and 19 had restricted zones of intramedullary edema involving one spinal segment or less (Group 3). The neurological state was determined using standard motor index scores at admission and at follow-up examination. Characteristically, the patients in Group 1 had admission motor scores significantly lower than the other two groups. At follow-up examination, the median percent motor recovery was 9% for Group 1, 41% for Group 2, and 72% for Group 3. These studies suggest that the MR imaging pattern observed in the acutely injured human spinal cord has a prognostic significance in the final outcome of the motor system. It is only when an accurate prognosis can be given at the outset that useful treatment data might be collected for homogeneous injury groups, and accurately based long-term planning made for the best patient care.