Factors associated with radiographic and clinical outcomes after posterior long-segment instrumentation for neurologically intact thoracolumbar fractures: a single-center retrospective study.

BACKGROUND: This study aimed to quantify radiographic correction and long-term maintenance, assess pain and health-related quality of life, and identify factors associated with outcomes after standardized posterior long-segment fixation for neurologically intact traumatic thoracolumbar junction fractures.

METHODS: This single-center retrospective cohort study included consecutive adults with acute traumatic T11-L2 fractures treated between March 2014 and February 2023 with posterior long-segment pedicle screw instrumentation (two levels above and two levels below, including fracture-level screws) without decompression. Patients required at least 24 months of radiographic follow-up, available pre-operative sagittal computed tomography images, and early post-operative and final lateral radiographs. Imaging parameters were vertebral compression angle (VCA) and anterior/posterior vertebral corpus height. Clinical outcomes were final Visual Analog Scale (VAS) and 36-item short form health survey (SF-36) scores, which were assessed cross-sectionally at final follow-up and therefore reflect final health status rather than change from pre-operative levels. Paired comparisons were used for longitudinal imaging changes, and multivariable linear regression with robust standard errors was used to evaluate factors associated with final outcomes.

RESULTS: Seventy-eight patients were included (mean age 40.2±13.9 years; 65.4% male), with a median follow-up of 48 months. VCA changed from 11.75° (7.83-16.48) preoperatively to 4.30° (2.55-6.65) early postoperatively and was 6.00° (4.00-8.80) at final follow-up, indicating limited correction loss over time. Restoration of both anterior and posterior vertebral body heights was observed, with partial loss at final follow-up. Final pain levels were low (VAS 1 [interquartile range=1-1]). In adjusted analyses, AO fracture type was associated with greater VCA loss and poorer SF-36 scores across several domains, particularly for AO type C fractures. However, the number of type C fractures was limited (n=9). Superficial wound infection occurred in 5 patients (6.4%) and resolved with local care and antibiotics; no deep infection, implant failure, revision surgery, or junctional complications were observed.

CONCLUSION: Posterior long-segment fixation for neurologically intact T11-L2 fractures provided substantial early radiographic correction with generally limited long-term loss of alignment and low final pain levels. Nevertheless, radiographic correction did not necessarily translate into complete functional recovery, as reflected by persistent variability in SF-36 domains. Among the variables analyzed, AO fracture type showed the most consistent association with correction loss and patient-reported outcomes. These hypothesis-generating findings suggest that fracture morphology may be associated with outcomes and may help frame post-operative expectations and follow-up discussions in similar patient populations. However, confirmation in larger, prospective, and comparative studies is required.