Prediction of clinical height gain from surgical posterior correction of idiopathic scoliosis

Abstract

<jats:sec><jats:title>OBJECTIVE</jats:title><jats:p>The best predictors of height gain due to surgical correction are the number of fused vertebrae and the degrees of the corrected Cobb angle. Existing studies of predictive models measured the radiographic spinal height and did not report the clinical height gain. The aims of this study were to determine the best predictive factors of clinical height gain before surgical correction, construct a predictive model using patient population data for machine learning, and test the performance of this model on a validation population.</jats:p></jats:sec><jats:sec><jats:title>METHODS</jats:title><jats:p>The authors reviewed 145 medical records of consecutive patients who underwent surgery that included placement of posterior spinal instrumentation and fusion for idiopathic scoliosis between 2012 and 2016. Standing and sitting clinical heights were measured before and after surgery in patients who had been surgically treated under similar conditions. Multivariate analysis was then performed and the results were used to develop a predictive model for height gain after surgery. The data from the included patients were randomly assigned to a learning set or a test set.</jats:p></jats:sec><jats:sec><jats:title>RESULTS</jats:title><jats:p>In total, 116 patients were included in the analysis, for whom the average postoperative clinical height gain in a standing position was 4.2 ± 1.8 cm (range 0–11 cm). The best prediction model was calculated as follows: standing clinical height gain (cm) = 1 − 0.023 × sitting clinical height (cm) − 0.19 × Risser stage + 0.058 × Cobb preoperative angle (°) + 0.021 × T5–12 kyphosis (°) + 0.14 × number of levels fused. In the validation cohort, 91% of the predicted values had an error of less than one-half of the actual height gain.</jats:p></jats:sec><jats:sec><jats:title>CONCLUSIONS</jats:title><jats:p>This predictive model formula for calculating the potential postoperative height gain after surgical treatment can be used preoperatively to inform idiopathic scoliosis patients of what outcomes they may expect from posterior spinal instrumentation and fusion (taking into account the model’s uncertainty).</jats:p></jats:sec>

Surgical Outcome of Three-Dimensional Correction of Adolescent Idiopathic Scoliosis

“…Mean percentage height gain was 3.91%, ranging from 1.16 to 7.59%. This comes in accordance with Langlias et al (14) who showed that the mean preoperative clinical height was 160.9 ± 7.5 cm (range 140-179 cm) in the standing position and 82.6 ± 4 cm (range 73-92.5 cm) in the sitting position. The average postoperative clinical height gain in a standing position was 4.2 ± 1.8 cm (range 0-11 cm) (P< 0.001).…”

3D quasi-automatic spine length assessment using low dose biplanar radiography after surgical correction in thoracic idiopathic scoliosis

“…In our series, the height gain was 24.1 mm and correlated to the main Cobb angle. The average linear height gain and the factors correlated to spinal length gain found in the literature are summarized in Table 3 [2][3][4][5][6][7]. The different 2D measurement methods reported an average gain ranging from 27 mm to 46 mm but the average correction Cobb angle (ranging from 35 • to 45 • ) was a slightly better than ours.…”

“…We did not find a link between height gain and number of vertebrae fused compared other studies [3][4][5][6]. Our hypothesis is that we did not perform selective arthrodesis, so that the differences between the fused levels are consequently small as in the study by Morin et al [7]. The frontal curvature correction is strongly correlated to the height gain [2][3][4][5][6].…”

“…The second objective is to avoid the progression of scoliosis, which could evolve towards a restrictive respiratory syndrome. Surgical fusion correction can lead to a considerable improvement in height, from 27 to 46 mm [2][3][4][5][6][7]. Contrary to classical radiographic parameters (such as Cobb angle, sagittal or spinopelvic parameters), the assessment of the radiographic height gain is not calculated routinely.…”

“…Contrary to classical radiographic parameters (such as Cobb angle, sagittal or spinopelvic parameters), the assessment of the radiographic height gain is not calculated routinely. Several studies [2][3][4][5][6][7] have focused on the measurement of the spine length but also the height gains related to surgical correction. In most studies, the height gain is correlated with the Cobb angle correction [2][3][4][5][6] or the number of fused vertebrae [3][4][5][6].…”