• Jason Pui Yin Cheung, Cora Bow, Dino Samartzis, Kenny Kwan, and Kenneth Man Chee Cheung.
• Department of Orthopaedics and Traumatology, The University of Hong Kong, Hong Kong, SAR, China.
• J Orthop Surg (Hong Kong). 2016 Dec 1; 24 (3): 332-337.

PurposeTo assess the effect of frequent small distractions with a magnetically controlled growing rod (MCGR) on spinal length gain and achieved distraction length in children with early-onset scoliosis (EOS), and to determine whether the law of diminishing returns applies to this group of patients with MCGR.MethodsA consecutive series of 3 males and 4 females with EOS who underwent MCGR implantation at a mean age of 10.2 years and were followed up for a mean of 3.8 years were reviewed. Distraction was aimed at 2 mm monthly. The coronal Cobb angle, T1-S1 length gain, and achieved distraction length were measured at 6-monthly intervals.ResultsThe mean total number of distractions was 31. Four of the patients had problems that may have affected distractions. The mean coronal Cobb angle improved post-operatively and was maintained throughout the follow-up period. The mean T1-S1 length gain and achieved distraction length varied over the follow-up period and did not diminish with repeated lengthening.ConclusionsFrequent small distractions with the MCGR for EOS enable T1-S1 and achieved distraction length gain without significant reduction in gain after repeated lengthening.

19 keywords...

hide…