P0852 - Respiratory and Post-operative Outcomes in Early Onset Scoliosis Patients Treated with Rib Based Growing System: Single Centre Experience of 15 Years

Background/Purpose:
Rib based growing system have been presented as an alternative to improve clinical status, spinal deformity and pulmonary function in patients with early onset scoliosis. The aim of this study is to evaluate respiratory and postoperative long-term outcomes in early onset scoliosis patients who undergo a rib based growing system (RBGS).

Methods:
Retrospective single-center study of all early onset scoliosis patients treated with a RBGS and repeated lengthening procedures every six-months from 2005 to 2019 who had a minimum of two years of follow up. Demographic and primary coronal-sagittal Cobb angles were performed at preoperative, immediate postoperative, and last follow-up. Pulmonary function test was evaluated at pre-operative and last follow-up. Postoperative complications were analyzed until the last available examination.

Results:
Twenty-eight EOS patients (42.9% female) were enrolled in the study, with 14 (50.0%) neuromuscular, 9 (32.1%) congenital, 4 (14.3%) syndromic and 1 (3.6%). An average age of 7.3+2.9 years with a mean follow up of 6 yrs, and a mean of 6.0+3.0 subsequent lengthening procedures were found at six-month intervals. Average preoperative coronal Cobb angle was 59.1+15.0 with immediate postoperative angle of 33.5+14.4, and 59.4+23.5 angle at last follow-up. Mean preoperative sagittal Cobb angle showed 34.8+20.6 with immediate post-op angle of 27.9+13.2, and 37.6+20.2 angle at last follow-up. Fifteen out of twenty-eight patients (53.6%), were able to complete the PFTs with an average of four-PFTs per patient. Mean forced vital capacity (FVC) percentage changed from 74.4+43.3% initially to 50.3+14.7% at last expansion. The average of FEV1 changed from 71.9+38.4% initially to 50.2+15.3% at last expansion. See Table I.

A total of 37 complications in 20/28 (71.4%) patients were reported in the study. The most common complications were infection & wound dehiscence followed by device migration. See Table II.

Conclusion:
This 15-year follow-up study of EOS patients undergoing RBGS shows a concerning decrease in pulmonary function at last follow up visit. Coronal and sagittal corrections were maintained showing RBGS as an alternative to detain spine deformity. A high postoperative complication rate of 62.9% was reported among this population.