Predictors of rod length gain and sagittal alignment change after magnetically controlled growing rod lengthening

• Published in: Spine (Philadelphia, Pa. 1976) Pa. 1976), 2024-03, Vol.49 (5), p.349-355
• Main Authors: Asma, Ali, Fralinger, David, da Silva, Luiz Carlos Almeida, Mackenzie, W.G. Stuart, Gabos, Peter G., Mackenzie, William G., Shah, Suken A.
• Format: Article
• Language: English
• ISSN: 0362-2436; 1528-1159
• DOI: 10.1097/BRS.0000000000004616

This was a retrospective cohort study. There are preoperative characteristics that predict rod lengthening of magnetically controlled growing rods (MCGR). The lengthening of MCGR will lead to increased kyphosis. The amount of length gained by MCGR is variable, and predictors are lacking. Similarly, sagittal plane changes over the MCGR lengthening period have not been investigated. Patients with MCGR and a minimum 2-year follow-up were identified and those with previous spine surgery were excluded. Preimplantation, postimplantation, and last follow-up postlengthening radiographs were examined. Multiple linear regression analyses were used for rod length gain predictors. Fifty-six patients with early-onset scoliosis met inclusion criteria: nine idiopathic, five congenital, 14 neuromuscular, 20 syndromic, and eight skeletal dysplasia patients. No difference was seen between subtypes of early-onset scoliosis for rod length gain ( P =0.62). Shorter preoperative T1-T12 height and higher curve correction rate after implantation were significant predictors for rod length gain ( P