Premature spinal fusion after insertion of magnetically controlled growing rods for treatment of early-onset scoliosis: illustrative case

BACKGROUND Magnetically controlled growing rod (MCGR) systems have gained attention for their use in the treatment of early-onset scoliosis. Although traditional growing rods require frequent operations to lengthen the construct, MCGR allows for fewer open procedures and more frequent distractions by externally controlling rod elongation. Despite its appealing advantages, MCGR is not without limitations. OBSERVATIONS The authors describe a case of premature spinal autofusion before growing rod removal and termination of rod distraction. LESSONS This case highlights the limitations of MCGR systems, including length of use, body habitus restrictions, and risk of autofusion.

Benefits of Fixing 3 Proximal Vertebral Bodies vs. 2 in the Treatment of Early-Onset Scoliosis with Growing Rods

Background The outcomes of early-onset scoliosis (EOS) treated with growing rods in which 6 proximal anchor points on 3 vertebrae were used vs. 4 proximal anchor points on 2 vertebra were compared. Methods The records of patients with EOS treated surgically from January 2016 to December 2017 were retrospectively reviewed. In the Proximal 4 group, 2 vertebral bodies were anchored proximally with 4 anchor points; in the Proximal 6 group, 3 vertebral bodies were anchored proximally with 6 anchor points. Results Forty-two patients (mean age 5.11 ± 1.93 years) were included; 22 Proximal 4 group, 20 Proximal 6 group. Mean follow-up was 40.86 ± 13.49 months. The decrease in main curve Cobb angle postoperatively was significantly greater in the Proximal 6 group (33.22° vs. 19.08°) (P < 0.05). Cobb thoracic kyphosis (TK) was significantly decreased postoperatively in the Proximal 6 group (mean 20.70°); no significant decrease occurred in the Proximal 4 group. The main curve Cobb angle decrease at last follow-up was significantly greater in the Proximal 6 group (37.84° vs. 24.23°) (P < 0.05). Cobb TK was significantly decreased at last follow-up in the Proximal 6 group (mean 25.17°, P < 0.05); no significant decrease occurred in the Proximal 4 group. Instrument complications were lower in the Proximal 6 group (15.00% vs. 45.45%) (P < 0.05). No proximal junctional kyphosis was noted. Conclusion Fixing 3 proximal vertebral bodies with 6 anchors improves outcomes of EOS treated with growing rods, and has a lower rate of instrument-related complications.