Submuscular isola rod with or without limited apical fusion in the management of severe spinal deformities in young children - Preliminary report

Study Design. Retrospective review of the results of submuscular rod placement with and without limited apical fusion for the treatment of severe spinal deformities in young children. Objectives. To determine the success of this method for controlling severe deformities while allowing for spinal growth and to compare this method with previously reported results. Summary of Background Data. A variety of methods for controlling scoliosis in young children have been reported, but complications including spontaneous fusion, loss of correction, instrumentation failure, and limited spinal growth are common. Methods. The cases of 29 young children with progressive scoliosis or kyphoscoliosis as a result of a variety of diagnoses treated with a submuscular Isola rod and a postoperative orthosis were retrospectively reviewed. Eleven patients also had a short anterior and posterior apical fusion or convex hemiepiphysiodesis to aid in correction and stabilization of their deformity. The remaining 18 patients had a submuscular rod only. Results. The mean age at surgery was 6.7 years (range, 1-11 years). The initial preoperative mean magnitude of the major curve was 66 degrees (range, 42-112 degrees). After surgery this decreased to a mean of 38 degrees (range, 16-70 degrees). The most recent radiographs demonstrated a mean 47 degrees curve (range, 28-79 degrees). The mean number of lengthenings per patient has been two (range, 0-5). Nine patients have reached a suitable age and have been converted to a posterior spinal fusion and segmental spinal instrumentation. Nine complications have occurred in seven patients (24%). These included five hook displacements and three rod breakages. These were treated by hook reinsertion and rod exchange or sleeve and a repeat lengthening. There was one superficial infection treated medically. Conclusion. This technique is useful in the management of severe spinal deformities in young children who have either failed, or have a contra indication to, orthotic management. Complications are relatively frequent but well tolerated.