Neurological injury and patterns of sacral fractures.

To evaluate the morphological and neurological findings in sacral spine injuries, a retrospective study was conducted of all patients admitted to Erie County Medical Center over a 2-year period with the diagnosis of pelvic or sacral injury. Of these 253 patients, 44 were found to have sacral fractures and form the basis of this study. The type of fracture, neurological deficit, treatment, and outcome in these patients were analyzed. The patient population consisted of 25 males and 19 females, with a mean age of 34 years (range 15 to 80 years). The fractures were classified by the degree of involvement of the foramina and central canal. Fractures through the ala sacralis only (Zone I, 25 cases) or involving the foramina but not the central canal (Zone II, seven cases) were less likely to cause nerve injury (24% and 29%, respectively). Fractures involving the central canal (Zone III), both vertical (five cases) and transverse (seven cases), were more likely to cause neurological injury (60% and 57%, respectively). Neurological deficits in Zone I and II injuries were usually unilateral lumbar and sacral radiculopathies. Zone III deficits were usually bilateral and severe; bowel and/or bladder incontinence was present in six of the 12 patients in this group. Deficits generally improved with time; however, operative reduction and internal fixation may have been useful, particularly in patients with unilateral root symptoms. The treatment options are discussed, and previously published series of sacral fractures are reviewed. The authors conclude that the classification of sacral fractures described is useful in predicting the incidence and severity of neurological deficit.