Single vs Double Index Screws in Thoracolumbar Burst Fractures: A Retrospective Analysis

Retrospective study.

To assess the radiological, clinical, and neurological outcome of patients who had thoracolumbar burst fractures and had undergone short-segment posterior stabilization with single-index screw (SIS) or double-index screws (DIS) at the fractured vertebra.

We included patients with AO type A and B with thoracolumbar injury classification and severity score (TLICS) ≥ 5, load-sharing classification (LSC) score ≥ 7, and a follow-up period of more than 2 years. Of 94 patients, 45 had DIS fixation, and 49 had SIS fixation. All patients' pre-operative, immediate post-operative, and final follow-up visit X-rays were analyzed for Cobb's angle (CA), vertebral wedge angle (VWA), and vertebral body compression ratio (VBCR) in a neutral lateral view and transverse spinal area (TSA) in axial CT section. Clinical and neurological outcomes were assessed using the Visual Analog Scale (VAS) for back pain, the Oswestry Disability Index (ODI), and the American Spinal Injury Association (ASIA) Impairment Scale (AIS) at their final follow-up visit.

The radiological parameters between both groups showed significant differences in terms of CA, VWA, and VBCR at the latest follow-up (SIS: 12.5°, 15°, 80.1% vs DIS: 8.04°, 11.2°, 87.1%) (p < 0.05). VAS and ODI were better in the DIS group but were statistically insignificant (p > 0.05).

Short-segment posterior stabilization with DIS in the fractured vertebra resulted in radiologically better maintenance of CA, VWA, and VBCR compared to SIS. There were no significant differences in terms of clinical (VAS and ODI), neurological outcome (AIS), and spinal canal remodeling (TSA).