Comparison of Two Segment Combined Instrumentation and Fusion versus Three Segment Posterior Instrumentation in Thoracolumbar Burst Fractures: A Randomized Clinical Trial with 10 Years of Follow Up

Abstract

AIM: To compare the clinical and functional outcomes between combined anterior and posterior 2-segment spinal fusion and posterior 3-segment spinal fusion in patients with thoracolumbar (TL) burst fractures at risk for posttraumatic kyphosis without neurological deficit.

MATERIAL and METHODS: Twenty-seven patients with TL burst fracture, >20 degrees kyphosis and/or 50% collapse, and posterior ligament injury, but without neurological deficit, were randomly assigned into posterior and combined groups. Posterior treatment was 3-segment (1 level below, fractured level and 2 levels above) posterior spinal fusion. Combined treatment was including 1 cranial and 1 caudal levels posterior spinal fusion, followed by anterior corpectomy, cage, and bone grafting. Patients were followed-up for a mean duration of 117.7 +/- 8.7 months (range, 98-132 months). At the final follow-up, the clinical and functional means of the groups were compared using degree of kyphosis, visual analogue scale (VAS), and Roland-Morris and Oswestry scores.

RESULTS: Mean patient age was 38.5 +/- 2.4 years (range: 18-68 years). Fourteen and 13 patients were treated with the combined and posterior approach, respectively. Age (40.0 +/- 10.3 and 37.0 +/- 14.2 years; p=0.519), sex (female/male, 3: 10 and 5: 9; p=0.385), mechanism of injury (p=0.513), fractured levels (p=0.185), type of fracture (p=0.293), degree of kyphosis at initial admission (p=0.616), collapse (p=0.155), canal narrowing (p=0.280), follow-up (p=0.076) and accompanied limb fracture (p=0.374) were similar between groups. Duration of hospital stay was similar between two groups (p=0.102). However, blood loss was higher in combined group (195 ml versus 358ml, p=0.003). A 14.2 degrees correction was achieved in the posterior group and 16.9 degrees in the combined group (p=0.61). Loss of correction at the last follow-up visit was 2.1 degrees with a final kyphosis of 7.2 degrees in the posterior group, and 1.2 degrees with a final kyphosis of 5.5 degrees in the combined group. The differences in the correction of kyphosis (p=0.616), postop kyphosis (p=0.756), loss of correction (p=0.141) and final kyphosis (p=0.085) between the treatment groups were not significant. At the last follow-up visit of the posterior and combined groups, the VAS (16.4 +/- 14.8 vs. 17.6 +/- 16.6; p=0.685), Roland-Morris (27.2 +/- 27.3 vs. 29.6 +/- 20.5; p=0.519), and Oswestry scores (15.0 +/- 13.1 vs. 17.7 +/- 11.5; p=0.302) were similar.

CONCLUSION: Both treatment methods are similar in terms of clinical and functional outcomes.