Curve Progression in Children with Spinal Deformity after Removal of Vertical Expandable Prosthetic Titanium Ribs
Published on: 2018-09-25
Abstract
Purpose Vertical expandable prosthetic titanium rib (VEPTR) implants may be used in children with severe spinal deformities during the growth period before definite spinal fusion. The purpose of this study was to evaluate spinal deformities before, during and after VEPTR treatment, with special focus on potential differences between congenital and neuromuscular scoliosis. Methods Retrospective cohort study on a population of 15 children with a continuous documentation starting before VEPTR treatment and ending with the removal of hardware prior to spinal fusion. Radiologic measurements of scoliosis and of pelvic obliquity were performed in anteroposterior radiographs, while kyphosis, lordosis and spinal length were evaluated in lateral radiographs. Measurements were conducted before and after initial VEPTR implantation, in two years intervals during VEPTR treatment as well as before and after final VEPTR explanation. Results Initial implantation of VEPTR was able to significantly reduce the main curve, which increased again over time. However, scoliosis in children with congenital spinal deformity remained stable after implant removal, whereas neuromuscular scoliosis showed a significant deterioration of the main curve immediately after VEPTR removal. Bending films pre VEPTR and after explanation showed 50% and 24% curve flexibility, respectively. The primary achieved correction of pelvic obliquity remained unchanged after implant removal in patients with congenital scoliosis, but deteriorated in neuromuscular children. Conclusions After removal of long-standing VEPTR implants, spinal deformity in children with congenital scoliosis remained unchanged, suggesting an observing approach in the future. Bilateral VEPTR treatment using rib-to-pelvis constructs without touching the spine preserved some spinal flexibility in children with neuromuscular scoliosis. Level of Evidence Therapeutic Level IV