Sagittal contour restoration and canal clearance in burst fractures of the thoracolumbar junction (T12-L1): the efficacy of timing of the surgery.

The efficacy of timing of surgery (short segment fixation using transpedicular screws), in burst fractures of thoracolumbar spine was evaluated between May 1993 and October 1994. The patients were divided into two groups according to time elapsed between injury and operation. Cases operated on within the first 24 h were taken as the early surgery group (n = 10) and cases operated on later than 24 h after the injury were considered as the late surgery group (n = 8). The efficacy of treatment was assessed by evaluation of the sagittal index (SI) restoration and reduction of canal compromise. The pre- and postoperative values for SI and canal narrowing (CN) for both groups are as follows: Early preoperative SI-23.40 degrees, late preoperative SI-24.50 degrees, p = 0.53; early preoperative CN-0.47, late preoperative CN 0.52, p = 0.33; early postoperative SI-4.20 degrees, late postoperative SI-13.50 degrees, p = 0.0001; early postoperative CN-0.10, late postoperative CN-0.39, p = 0.0000. There is still controversy concerning the relationship between canal narrowing and neurologic deficit, and the effect, if any, of decompression on neural recovery. Nevertheless, if the main aim of the surgical procedure is to restore the SI and decompress the neural canal, then other alternatives of decompression and realignment should be preferred to indirect reduction using short segment transpedicular fixation in cases to be operated on later than 24 h after injury.