Minimally Invasive Bipolar Technique for Scoliosis in Rett Syndrome-Results and Complications in a Series of 22 Cases.

Background: This is a retrospective study. The aim of this study is to report the results of bipolar minimally invasive fusionless surgery for scoliosis in Rett syndrome with a minimum follow-up of 2 years. Conservative treatment is often not effective in Rett syndrome scoliosis. Posterior spinal fusion (PSF) has a high rate of complications; early surgery using traditional growing rods (TGRs) controls the deformity while preserving spinal and thoracic growth before arthrodesis. The need for surgical rod lengthening still has a high rate of complications and costs. Methods: We recorded the clinical and radiological outcomes of 22 consecutive patients with Rett scoliosis who underwent bipolar fusionless surgery with a mean follow-up of 56 months (24-99). We performed a bilateral construct with rods (with or without a self-sliding device) anchored proximally with four hook claws distally to the pelvis by ilio-sacral (IS) screws through a minimally invasive approach. Results: The Cobb angle was reduced from 74.4° initially to 28.9° postoperatively and to 25.7° at the last follow-up, which corresponds to a 65% correction of the initial deformity. The gain was maintained at the last follow-up. None of the patients required spinal fusion at skeletal maturity (55% of our patients reached skeletal maturity). There was a gain in body weight (27.97 kg at preoperative time and 33.04 kg at postoperative time). The surgical complication rate was 32%. Conclusions: We recorded the stable correction of deformities and weight gain over time using the bipolar minimally invasive fusionless technique with a reduced rate of complication compared to arthrodesis. The arthrodesis was not necessary at skeletal maturity, thanks to the delayed natural ankylosis of a fixed spine.