Measurement of damaged segment deformity in the thoracic and lumbar spine with spiral computed tomography to calculate the required correction

Introduction The more accurate is the measurement of the parameters for correcting the deformity of damaged spinal segments the more accurate will be the restoration of the sagittal profile and original anatomy of the spine. Purpose Substantiation of calculated indicators for deformity correction in one or two damaged spinal motion segments in the thoracic and lumbar spine according to spiral computed tomography. Material and methods The material for the study was the results of spiral computed tomography (SCT) of an anatomically unchanged thoracic and lumbar spine in 25 patients (12 women and 13 men aged 18 to 60 years). The study model consisted of three vertebral bodies and four adjacent discs from T4 to L4. Anterior and posterior dimensions of the vertebral bodies, intervertebral discs, and segmental deformity angle α (formed by the lower endplate of the overlying vertebra and the upper endplate of the underlying vertebra) were measured using RadiAnt computer software in the midsagittal projection. Damage to the body of the middle vertebra with adjacent discs was modeled, the dimensions of which were calculated from the adjacent vertebral bodies and adjacent discs. Statistical processing of the material was carried out using the computer software SPSS Statistics. Results The measurement error of the anterior interbody spaces was 1.4 ± 0.4 mm, the posterior interbody spaces were 1.3 ± 0.5 mm, the error in calculating the segmental deformation angle α was 2.5 ± 0.6 degrees, what indicates the high accuracy of the proposed method. Discussion The use of absolute deformity values as a standard for surgical intervention in the treatment of vertebral fractures is complicated by varieties of normal anatomy. Conclusion The proposed calculations for the restoration of the anterior and posterior interbody distances, as well as the angle of segmental deformity α after a spinal cord injury of the thoracic and lumbar spine provide an approach to the target individualized anatomical dimensions.