Weight Gain and Nutritional Improvement After Magnetically Controlled Growing Rod Surgery in Early-Onset Scoliosis: A Single Centre Analysis of 68 Patients

Abstract

Background: Early-onset scoliosis (EOS) is frequently associated with complex spine and chest wall deformities that may lead to severe cardiopulmonary impairment and malnutrition. The aim of this study is to evaluate the change in the nutritional status of EOS patients after treatment with magnetically controlled growing rod instrumentation (MCGR) in a single center.

Methods: We prospectively collected data of patients treated with MCGR for EOS in a single center. Exclusion criteria were <2 years' follow-up and incomplete weight-for-age Z-scores (WAZ) data. Preoperative and postoperative WAZ, radiographic parameters, including major coronal curve, kyphosis angle, space available for lung ratios, thoracic height, and unplanned returns to the operating room (UPROR), were analyzed. SD and 95% Confidence intervals (CI) are presented with means.

Results: Sixty-eight patients (37 males/31 females) were included. The mean age at surgery was 8.2 years (SD 2.8, range 1.8-14.2), and the mean follow-up time was 3.8 years (SD 1.0, range 2.1-6.8). The study population was categorized by the primary diagnosis as follows: 23 neuromuscular, 18 idiopathic, 15 congenital, and 12 syndromic patients. The major coronal curve improved between the preoperative and latest visits by 40% ( P <0.005, SD 27, CI 33-47), while the space available for lung ratios improved by 8% ( P <0.005, SD 13, CI 5-12). Thoracic height increased by 25% ( P <0.005, SD 13, CI 22-28), and kyphosis angle decreased by 25% ( P <0.005, SD 26, CI 9-39). Eighteen patients (27%) required a total of 53 UPRORs. WAZ improved significantly between the preoperative and the latest follow-up ( P =0.005). Regression analysis showed WAZ improvements were most significant in the underweight patients and the Idiopathic or Syndromic EOS patients. UPROR was not associated with deterioration in WAZ.

Conclusions: Treatment of EOS patients with MCGR resulted in an improvement in nutritional status, as evidenced by the significant increase in WAZ. Underweight, Idiopathic and Syndromic EOS patients, and those who required UPROR all had significant improvement in their WAZ with MCGR treatment.

Level of evidence: Therapeutic Study-Level II.