Unstable burst fractures of the thoraco-lumbar junction: treatment by posterior bisegmental correction/fixation and staged anterior corpectomy and titanium cage implantation.

BACKGROUND: Controversy exists about the best treatment of unstable thoraco-lumbar (TL) burst fractures. Kyphosis correction and canal decompression in case of a neurological deficit are recognized treatment objectives, and various conservative and surgical strategies have been proposed. This prospective observational study evaluates the benefits and risks of a posterior bisegmental transpedicular correction/fixation and staged anterior corpectomy and titanium cage implantation in unstable TL junction burst fractures.
METHOD: 20 consecutive patients with a single-level traumatic unstable burst fracture at the TL junction were operated on by a bisegmental posterior correction/fixation, followed by anterior corpectomy and titanium cage implantation 7-10 days later. The radiological and clinical course is documented over a period of 24 months.
FINDINGS: The mean posttraumatic loss of anterior vertebral body height was 58% (45-70%). The posttraumatic mean regional kyphosis was 16 degrees and could be corrected by the posterior approach to a mean lordosis of 2 degrees. Mean secondary loss of the kyphosis correction was 3 degrees over 24 months. No hardware failure occurred, and construct stability was observed in all 20 patients. One surgical complication occurred during the posterior approach, and three transient surgical complications by the anterior approach. 12 of the 14 patients with an initial neurological deficit recovered an average of 1.5 grades on the ASIA scale. At 24 months postoperatively, the mean regional TL back pain on a VAS (0-10) was 1.6, and the mean pain at the anterior approach site was 1.2.
CONCLUSION: Posterior bisegmental transpedicular correction/fixation and staged anterior corpectomy and titanium cage implantation is a safe and reliable surgical treatment option in unstable TL junction burst fractures. The advantages of this technique are a complete kyphosis correction, immediate stability, maintenance of kyphosis correction, and complete spinal canal decompression in case of a neurological deficit. However, these advantages have to be carefully weighed against the double approach morbidity.