Fifty-eitht patients having unstable thoracic and lumbar spine fractures who had surgical treatment were reviewed in regards to the radiographic findings of the spinal columns and neurologic changes of the injured cord and/or roots. Among them, 25 patients were paralytics, and 33 were non-paralytics. l. Unstable spine fracture which occurred in thoracic level showed high incidence of neurological injury (six of seven patients:85.7%); high incidence of complete paralysis (five of seven patients:71.4%) compared with that of the thoracolumbar and lumbar fractures. 2. Among the various spine injuries, fracture-dislocation showed high incidence of neurological injury (ten of eleven patients:90.9%) including complete paralysis compared with that of the burst, compression and seat-belt types. 3. Displacement of vertebral body measured on lateral plane X-ray showed significant difference (p<0.001) between paralytic and non paralytic groups, but there were no differences in kyphotic angle and anterior height loss between two groups. 4. A-P diameter of compromised neural canal and percent of compromised surface of neural canal showed significant differences between paralytic and non-paralytic groups (canal diameter:p<0.05, canal compromise :p<0.05). 5. Fracture shapes around the spinal canal which is shown on C-T scan, were grouped into 5 types according to the severity of bony disruption and displacement; Type I . Sagittal fracture line through anterior and posterior elements. Type II. Retropulsion of bone fragment into the canal with intact posterior element. Type III. Retropulsion of bone fragment into the canal with fracture of posterior element. Type IV. Severe comminution of body and disruption of posterior element around the canal. Type V. Fracture-dislocation of comminuted vertebral body and neural arch (with or without double margin sign, with or without vacant facet sign). 6. Neural deficit was high in type IV (fracture with disruption of vertebral body and osseous neural arch around the canal) and type V (fracture-dislocation of comminuted vertebral body and neural arch with double margin sign) injuries which showed severe bony disruption and displacement.