Short-segment posterior instrumentation of thoracolumbar fractures as standalone treatment

summary This article reports on the radiographic outcome of unstable thoracolumbar fractures managed with short segment posterior instrumentation as standalone treatment. Short segment posterior instrumentation is the method of choice for unstable thoracolumbar injuries in our unit. It is considered to be adequate treatment in cases with an intact posterior longitudinal ligament, and Gaines score below 7; as well as fracture dislocations, and seatbelt-type injuries, without loss of bone column bearing integrity. Sixty-five consecutive patients undergoing this surgery were studied. Patients were divided into two main cohorts, namely the ‘Fracture group’ (n=40) consisting of unstable burst fractures and unstable compression fractures; and the ‘Dislocation group’ (n=25) consisting of fracture dislocations and seatbelt-type injuries. The groups reflect similar goals in surgical treatment for the grouped injuries, with reduction in loss of sagittal profile and maintenance thereof being the main aim in the fracture group, appropriately treated with Schantz pin constructs; and maintenance in position only in the dislocation group, treated with pedicle screw constructs. Data were reviewed in terms of complications, correction of deformity, and subsequent loss of correction with associated instrumentation failure. Secondly, factors influencing the aforementioned were sought, and stratified in terms of relevance. Average follow-up was 278 days for the fracture group and 177 days for the dislocation group. There was an average correction in kyphotic deformity of 10.25 degrees. Subsequent loss in sagittal profile averaged 2 degrees (injured level) and 5 degrees (thoracolumbar region) for the combined fracture and dislocation group. The only factor showing a superior trend in loss of reduction achieved was the absence of bone graft (when non-fusion technique was employed). Instrumentation complications occurred in two cases (bent connection rod, and 10 degrees loss in regional sagittal profile following 2 degrees of reduction respectively). These complications represent 3.07% hardware failure in total. Conclusion: Short segment posterior instrumentation is a safe and effective option in the treatment of unstable thoracolumbar fractures as a standalone measure. SAOJ Winter 2009.qxd:Orthopaedics Vol3 No4 5/10/09 2:40 PM Page 68