Congenital Kyphosis: Progressive Correction With an Instrumented Posterior Epiphysiodesis: A Preliminary Report

Purpose: Congenital kyphosis is a rare condition. In this case series we sought to identify the outcomes and complications of posterior instrumented fusion and the resultant epiphysiodesis effect in uniplanar congenital kyphosis in pediatric patients. Method: Pediatric patients were included if treated for a uniplanar congenital kyphotic deformity treated with posterior instrumented spinal fusion between October 2006 and August 2017, with a minimum of 2 years of follow-up. Patients were excluded if a coronal deformity >10 degrees was present. Results: Six patients met the inclusion criteria. Mean age at surgery was 3.6 years. The mean kyphotic deformity before surgery was 49.7 degrees. All patients underwent posterior instrumented fusion with autogenous iliac crest graft and a cast or brace postoperatively. One patient showed a loss of motor evoked potential on prone positioning which returned to normal on supine positioning. No patient showed any postoperative neurological deficits. One patient was diagnosed with a wound infection which was successfully treated with oral antibiotics. By a follow-up of 5.4 years (range, 2.2 to 10.9 y) there was no failure of instrumentation. An epiphysiodesis effect (a difference of ≥5 degrees in the kyphotic deformity measured between the immediate postoperative and final follow-up lateral whole spine XR) of 16.2 degrees (range, 7.2 to 30.9 degrees) was seen in 5 patients. The mean annual epiphysiodesis effect was 2.7 degrees (95% confidence interval, 1.4-4.1 degrees). No kyphosis proximal to the instrumentation was observed for the duration of follow-up. Conclusion: Posterior instrumented fusion and epiphysiodesis is safe and effective. The epiphysiodesis effect occurs in 5/6 of cases, and our data suggests that the procedure is associated with an acceptable blood loss and a low incidence of neurological complications.