Two additional augmenting screws with posterior short-segment instrumentation without fusion for unstable thoracolumbar burst fracture - Comparisons with transpedicular grafting techniques.

BACKGROUND: Transpedicular grafting techniques with posterior short-segment instrumentation have demonstrated to prevent high implant failure in unstable thoracolumbar burst fractures. We tested our hypothesis that short-segment instrumentation with two additional augmenting screws in the injured vertebra could provide stability and was similar to those of the transpedicular grafting technique.

METHODS: Twenty patients belonged to group A; treated with short-segment pedicle screw fixation and reinforced by two augmenting screws at the fractured vertebra. Group B had thirty-one patients; the fractured vertebra was augmented with transpedicular autogenous bone graft. Group C had twenty patients; the injured vertebra was strengthened with calcium sulfate cement. Clinical outcome and radiographic parameters were compared.

RESULTS: Group A had the least blood loss (101.7 ± 72.5 vs. 600 ± 403.1 vs. 247.5 ± 164.2 ml, p < 0.001) and the least operation time (142.0 ± 57.2 vs. 227.2 ± 43.6 vs. 161.6 ± 28.5 min, p < 0.001). However, group A had the highest collapsed rate of the body height at the 18-month follow-up (10.5 ± 7.0 vs. 4.6 ± 4.8 vs. 7.2 ± 8.5%, p = 0.002). The failure rate, include implant failure or loss of 10° or more of correction, group B had the lowest failure rate (10% vs. 3.2% vs. 10%, p = 0.542). The group A had the highest rate of return to their previous employment (50% vs. 38% vs. 35%, p = 0.265).

CONCLUSIONS: Compared with transpedicular grafting techniques, additional two "augmenting screws" in the fracture vertebra with short-segment instrumentation are sufficient for one-level thoracolumbar burst fracture.