Comparison of surgical treatment in Lenke 5C adolescent idiopathic scoliosis: anterior dual rod versus posterior pedicle fixation surgery: a comparison of two practices.
ABSTRACT Multicenter analysis of 2 groups of patients surgically treated for Lenke 5C adolescent idiopathic scoliosis (AIS).
Compare patients with Lenke 5C scoliosis surgically treated with anterior spinal fusion with dual rod instrumentation and anterior column support with patients surgically treated with posterior release and pedicle screw instrumentation.
Treatment of single, structural, lumbar, and thoracolumbar curves in patients with AIS has been the subject of some debate. Advocates of the anterior approach assert that their technique spares posterior musculature and may save distal fusion levels, and that with dual rods and anterior column support the issues with nonunion and kyphosis have been obviated. Advocates of the posterior approach assert that with the change to posterior pedicle screw based instrumentation that correction and levels are equivalent, and the posterior approach avoids the issues with nonunion and kyphosis. This report directly compares the results of posterior versus anterior instrumented fusions in the operative treatment of adolescent idiopathic Lenke 5C curves.
We analyzed 62 patients with Lenke 5C based on radiographic and clinical data at 2 institutions: 31 patients treated with posterior, pedicle-screw instrumented fusions at 1 institution (group PSF); and 31 patients with anterior, dual-rod instrumented fusions at another institution (group ASF). Multiple clinical and radiographic parameters were evaluated and compared.
The mean age, preoperative major curve magnitude, and preoperative lowest instrumented vertebral (LIV) tilt were similar in both groups (age: PSF = 15.5 years, ASF = 15.6 years; curve size: PSF = 50.3 degrees +/- 7.0 degrees , ASF = 49.0 degrees +/- 6.6 degrees ; LIV tilt: PSF = 27.5 degrees +/- 6.5 degrees , ASF = 27.8 degrees +/- 6.2 degrees ). After surgery, the major curve corrected to an average of 6.3 degrees +/- 3.2 degrees (87.6% +/- 5.8%) in the PSF group, compared with 12.1 degrees +/- 7.4 degrees (75.7% +/- 14.8%) in the ASF group (P < 0.01). At final follow-up, the major curve measured 8.0 degrees +/- 3.0 degrees (84.2% +/- 5.8% correction) in the PSF group, compared with 15.9 degrees +/- 9.0 degrees (66.6% +/- 17.9%) in the ASF group (P = 0.01). This represented a loss of correction of 1.7 degrees +/- 1.9 degrees (3.4% +/- 3.7%) in the PSF group, and 3.8 degrees +/- 4.2 degrees (9.4% +/- 10.7%) in the ASF group (P = 0.028). The LIV tilt decreased to 4.1 degrees +/- 3.4 degrees after surgery in the PSF group, and 4.5 degrees +/- 3.7 degrees in the ASF group. At final follow-up, the LIV tilt was 5.1 degrees +/- 3.5 degrees in the PSF group, and 4.5 degrees +/- 3.7 degrees in the ASF group. EBL was identical in both groups, and length of hospital stay was significantly (P < 0.01) shorter in the PSF group (4.8 vs. 6.1 days). There were no complications in either group which extended hospital stay or required an unplanned second surgery.
At a minimum of 2-year follow-up, adolescents with Lenke 5C curves demonstrated statistically significantly better curve correction, less loss of correction over time, and shorter hospital stays when treated with a posterior release with pedicle screw instrumented fusion compared with an anterior instrumented fusion with dual rods for similar patient populations.
[Show abstract] [Hide abstract]
ABSTRACT: Clinical, radiological, and Scoliosis Research Society-22 questionnaire data were reviewed pre-operatively and two years post-operatively for patients with thoracolumbar/lumbar adolescent idiopathic scoliosis treated by posterior spinal fusion using a unilateral convex segmental pedicle screw technique. A total of 72 patients were included (67 female, 5 male; mean age at surgery 16.7 years (13 to 23)) and divided into groups: group 1 included 53 patients who underwent fusion between the vertebrae at the limit of the curve (proximal and distal end vertebrae); group 2 included 19 patients who underwent extension of the fusion distally beyond the caudal end vertebra. A mean scoliosis correction of 80% (45% to 100%) was achieved. The mean post-operative lowest instrumented vertebra angle, apical vertebra translation and trunk shift were less than in previous studies. A total of five pre-operative radiological parameters differed significantly between the groups and correlated with the extension of the fusion distally: the size of the thoracolumbar/lumbar curve, the lowest instrumented vertebra angle, apical vertebra translation, the Cobb angle on lumbar convex bending and the size of the compensatory thoracic curve. Regression analysis allowed an equation incorporating these parameters to be developed which had a positive predictive value of 81% in determining whether the lowest instrumented vertebra should be at the caudal end vertebra or one or two levels more distal. There were no differences in the Scoliosis Research Society-22 outcome scores between the two groups (p = 0.17). In conclusion, thoracolumbar/lumbar curves in patients with adolescent idiopathic scoliosis may be effectively treated by posterior spinal fusion using a unilateral segmental pedicle screw technique. Five radiological parameters correlate with the need for distal extension of the fusion, and an equation incorporating these parameters reliably informs selection of the lowest instrumented vertebra. Cite this article: Bone Joint J 2014;96-B:1082-9.08/2014; 96-B(8):1082-1089. DOI:10.1302/0301-620X.96B8.33837
[Show abstract] [Hide abstract]
ABSTRACT: Failure to select the appropriate lowest instrumented vertebra (LIV) in selective lumbar fusion (SLF) for thoracolumbar/lumbar curves (LC) can result in adding-on in the lumbar curve (LC) or the need for fusion extension due to a decompensating thoracic curve (TC). The selection criteria that predict optimal outcomes still need to be refined. The objectives of the current study were to identify risk factors for failure of anterior scoliosis correction and fusion (ASF) as well as predictors of optimal outcomes and ASF efficacy for SLF.European Spine Journal 06/2014; 23(12). DOI:10.1007/s00586-014-3405-9 · 2.47 Impact Factor
[Show abstract] [Hide abstract]
ABSTRACT: Study Design. A retrospective radiographic analysis.Objective. To assess the effect of unfused segments in the reconstitution of coronal balance after posterior selective thoracolumbar/lumbar (TL/L) curve fusion for adolescent idiopathic scoliosis.Summary of Background Data. Current literature suggests that compensatory changes occur after selective TL/L curve fusion surgery. Hitherto the roles of the unfused levels in coronal balance reconstitution have not fully understood.Methods. Radiographic data of idiopathic scoliosis patients that underwent selective posterior TL/L curve fusion at our hospital before October 2011 with a minimum of 2 years follow-up period was retrospectively analyzed. Changes of coronal trunk shift during the follow-up period were studied and multiple linear regression analysis was performed to determine its correlation with changes of upper and lower curve of unfused thoracic segments, instrumented segments angle, distal unfused segments angle and coronal sacral inclination.Results. A total of 43 patients were included in this study. Pre-operative and first erect radiographs demonstrated trunk shifts of 21.1mm and 18.7mm respectively, showing no significant differences (P = 0.205). At the last follow-up, it compensated to 9mm, which showed significant differences (P<0.01). Regression analysis of all patients showed that coronal trunk shift changes only correlated with distal unfused segments angle changes. Subgroup analysis based on the magnitude of preoperative thoracic curve found that only distal unfused segments had an impact on coronal balance reconstitution. However, subgroup analysis based on the flexibility of preoperative thoracic curve showed that both proximal unfused thoracic segments and distal unfused lumbar segments contributed to coronal balance compensation in patients with a thoracic curve flexibility rate of more than 70%.Conclusions. The reconstitution of coronal balance was mainly compensated by distal unfused segments after selective posterior fusion of TL/L idiopathic scoliosis. The effect of unfused thoracic segments in coronal balance reconstitution mainly depended on its flexibility.Spine 09/2014; 39(24). DOI:10.1097/BRS.0000000000000602 · 2.45 Impact Factor