Analysis of a Hybrid Spine Fixation Approach for the Treatment of Unstable Thoracolumbar Fractures

Introduction The treatment of unstable thoracolumbar burst fractures and fracture dislocations of the thoracolumbar spine remains ever evolving. Anterior or posterior approaches both have equal efficacy, but the posterior approach has been preferred in our study due to its ease of application, less extensile nature, and reduced intra-operative bleeding. Posterior approaches can employ short-segment fixation or long-segment fixation techniques. Long segment fixation may need implant removal later to increase mobility in nonfusion surgeries. The thoracolumbar segment is a transition zone where the thoracic spine is a less flexible zone, and the lumbar spine is a more flexible zone. Lumbar motion is important to preserve. Hence, we proposed to study spinal fixation two levels above and one level below the fracture for stabilization. This may provide increased stability along with preservation of the motion segment at the lumbar level. Methods We retro-prospectively reviewed the results of unstable thoracolumbar junction fractures with incomplete or intact neurology in 34 consecutive cases operated with alternate two above and one below fixation approach between June 2018 and June 2019 at our institute. Five cases were excluded due to incomplete follow up and the remaining 29 patients were included in the study. Regular follow-up in the postoperative period at three, six, and 12 months was conducted. Data analysis was done by SPSS software version 22 (IBM Corp., Armonk, NY). Results Twenty-nine patients were included in the study out of which 16 were males and 13 were females. The average age was 36.31±1.46 years (range, 14-60 years). The average follow-up duration was 14.31 months. The average injury to surgery interval was 7.17±7.31 days (range, 1-30 days). On analysis via paired t-test, pre-operative kyphotic angle (mean=20.06±8.34º) improved to immediate post-operative (mean=8.44±5.76º, p=0.0001). The postoperative kyphotic angle at 12 months follow-up showed significant stability (Mean=14.13±5.27º, p=0.0001). A median average pre-operative neurological compromise was ASIA score C and Frankel Grade C and the median average disability was an ODI score of 61%-80%. At the end of 12 months of follow-up the median average neurological compromise improved to ASIA Score D and Frankel Grade D and the median average disability improved to an ODI score of 21%-40%. Conclusion Two levels above and one level below hybrid pedicle screw fixation with decompression for the treatment of unstable thoracolumbar fractures with partial and intact neurology was successful within the limited time frame we had for follow-up in preserving progressive post-operative kyphosis, preserving one-motion segment, improving the neurological outcome and disability of the patients without any major complications.