Mono-Segment Fixation Versus Short-Segment Fixation in Adult Patients With Thoracolumbar Spine Fractures: A Randomized Controlled Trial.

Background Thoracolumbar spine fractures account for the majority of all spinal injuries and pose a significant challenge in trauma care. Fixation techniques have evolved over the decades, with pedicle screw fixation becoming the norm. However, the debate continues regarding the number of vertebral levels that should be included in the fixation construct for optimal outcomes in case of single-level injuries. While long-segment fixation provides robust stability, it sacrifices motion segments, potentially increasing stiffness and adjacent segment degeneration. Short-segment fixation (SSF), involving one vertebra above and below the fracture, reduces stiffness and implant cost. Mono-segmental fixation (MSF), a recently introduced concept, advocates instrumenting only the fractured vertebra and one adjacent vertebra either above or below. We believe that MSF could provide outcomes similar to SSF with fewer complications, shorter operative times, and reduced blood loss in specific fracture patterns. Hence, this study was designed as a single-center randomized controlled trial to test this hypothesis. Methodology Twenty-six patients were randomized into the two intervention groups: Group A (MSF, n = 13, 50%) and Group B (SSF, n = 13, 50%). After the intervention, the patients followed a standard postoperative care regimen and rehabilitation protocol. All patients underwent open surgery. Radiographs were obtained at regular intervals, and the outcome variables were recorded up to one year following surgery. Sagittal index (SI), anterior vertebral height loss (AVHL), Cobb's angle (CA), local kyphotic angle (LKA), and implant failure were the radiological outcome measures studied. The other parameters assessed were surgical blood loss, postoperative drain volume, surgical time, pain, and wound complications. Results The groups were comparable for mean age, gender distribution, AO fracture type, and mechanism of injury (P > 0.05). The mean change between observations at one year and immediate postoperative radiographs in SI, AVHL, and CA were similar between the groups (P > 0.05). The mean change in LKA was higher in the MSF group (P = 0.018, 95% confidence interval (CI) 0.78, 7.70). While the MSF group demonstrated reduced intraoperative blood loss (P = 0.055, 95% CI -64.89, -2.80) and surgical time (P = 0.039, 95% CI, -24.74, -0.64), both groups had similar drain volume (P = 0.443, 95% CI -41.24, -0.21) and pain Visual Analog Scale (VAS) scores throughout the follow-up period (P > 0.05). Conclusions MSF could be an effective alternative to SSF in selected thoracolumbar fracture patterns with both pedicles and one end plate intact, offering similar radiological outcomes with reduced surgical morbidity.