Study Design. Retrospective review. Objective. To report the technique and results of vertebral column decancellation (VCD) for the management of sharp angular spinal deformity. Summary of Background Data. The goal of management of sharp angular spinal deformity is to realign the spinal deformity and safely decompress the neurological elements. However, some shortcomings related to current osteotomy treatment for these deformities are still evident. Methods. From January 2004 to March 2007, 45 patients (27 males/18 females) with severe sharp angular spinal deformities at our institution underwent VCD. The diagnoses included 29 congenital kyphoscoliosis and 16 Pott's deformity. The operative technique included multilevel VCD, disc removal, osteoclasis of the concave cortex, compression of the convex cortex accompanied by posterior instrumentation with pedicle screws. Preoperative and postoperative radiographic evaluation was performed. Intraoperative, postoperative and general complications were noted. Results. For a kyphosis type deformity, an average of 2.2 vertebrae was decancellated (range, 2to 4 vertebrae). The mean preoperative kyphosis was +98.6° (range, 82° to 138°), and the meankyphosis in the immediate postoperative period was +16.4° (range, 4° to 30°) with an averagepostoperative correction of +82.2° (range, 61° to 124°). For a kyphoscoliosis type deformity, thecorrection rate was 64% in the coronal plane (from 83.4° to 30.0°) postoperatively and 32.5°(61% correction) at 2 years follow-up. In the sagittal plane, the average preoperative curve of88.5° corrected to 28.6° immediately after surgery and to 31.0° at 2 years follow-up. All patientshad solid fusion at latest follow-up. Complications were encountered in 8 patients (17.8%) andincluded transient neurological deficit and complete paralysis (n = 1). Conclusion. Single stage posterior vertebral column decancellation (VCD) is an effective option to manage severe sharp angular spinal deformities

INTRODUCTION. Surgical correction of spinal deformities in the growing child can be applied with or without fusion. Sublaminar wiring, first described by Luque, allows continuation of growth of the non-fused spine after correction of the deformity. Neurological complications and wire breakage are the main clinical problems during the introduction and removal of currently used sublaminar wires. In this pilot study a posterior hybrid construction with the use of a medical-grade UHMWPE (Dyneema Purity®) sublaminar wire was assessed in an ovine model. We hypothesized that such a hybrid construction can safely replace current titanium laminar wires, while providing sufficient stability of the non-fused spinal column with preservation of growth. MATERIALS AND METHODS. This study included 6 Tesselaar sheep, age 7±2months. Two pedicle screws (Legacy system, Medtronic) were placed at lumbar level. Four consecutive laminae were attached to two titanium bars (4.5 mm) using 3 mm diameter UHMWPE (Dyneema Purity®) on the left side and 5 mm diameter on the right side. The sublaminar wires were fixed with a double loop sliding knot and tightened with a tensioning device. As a control, in one animal titanium sublaminar wires (Atlas cable, Medtronic) were applied. After sacrifice the spine of the animals was harvested. Radiographs were taken and CT scans were performed. The vertebrae were dissected and placed in formaldehyde for macroscopic and histological evaluation. RESULTS. The animals were sacrificed after a (minimal) postoperative period of 15 weeks. One animal developed a wire fistula and one animal died the first postoperative day due to complications of the anesthesia. None of the 3 or 5 mm knots loosened and no neurological complications occurred. An average of 8.7 mm growth was seen over the segment operated on. Computed tomography confirmed the preserved stability. Even though no decortication was performed, variable bone bridges with fused levels were seen on CT. Macroscopic and histological analysis showed no inflammation at lamina and dura levels containing Dyneema Purity®, with the exception of the case with the fistula where it was observed locally. DISCUSSION. This pilot animal model study shows that the UHMWPE laminar wire made by Dyneema Purity® has good handling and tensioning properties and can provide sufficient stability in fusionless spinal instrumentation while allowing substantial growth. The examined model showed to be a feasible spinal study model, without occurrence of neurological problems. Reactive periostal bone formation with fusion levels led to some restrictions in this model. In the future it will be necessary to test the described construction in a large animal scoliosis model

Introduction. The aim of the treatment of children with early onset scoliosis is controlling growth of the spine. Whatever the etiology, early progressive deformations require multiple stages of surgery usually performed every 6–12 months. One have to be reckoned with complications requiring additional surgical intervention. Objective. The aim of the study is to present a new method of surgical treatment of early onset scoliosis involving the implantation of specially constructed implants to allow three dimensional correction of spinal deformity with a preserved capacity to continue the growth of spine without distraction staged operations followed by final spondylodesis in mature spine. Material. The clinical material consists of homogeneous group of patients: 8 girls and a one boy aged 6 to 14 years (mean age = 9 years). The estimated group four children had a single-curve, four children had a double-curve, while one child was affected by congenital kyphosis. The follow up ranged from 2 to 17 months (mean = 13.5 months). Method. Efficacy of spinal deformity correction using a “growing implants” was estimated by Cobb andgle measurement of the curvature 1/before the operation, 2/after surgery and 3/follow up. Results. During surgery, all patients obtained a large correction of curvature ranging from 50% to 100% (on average −70%). The degree of correction was directly dependent on the size of the initial deformation of 62 to 120 ° (average 77 °). During the entire period of observation in four children we have not identified the loss of correction or fits within the limits of measurement error. In one child thirty degree-loss correction stemmed from too selective implantation of the implants. During additional surgery the stabilization was extended to the extra two motor segments witch resulting in full correction. In one patient, due to rapid growth, rods were needed to be replaced for longer, because of the risk of pulling out from the lower screws. In one case we observed further correction during follow up. Conclusions. Using the method we obtained a very good correction in the first stage of treatment. Maintenance of correction does not require any intermediate staged operating procedures. Patients do not require corrective brace. Using “growing implants” in the early onset scoliosis one avoid complications peculiar to current growth-sparing procedures. These patients would have had 15 lengthening procedures after their initial correction if treated by conventional growing rod methods