Characterizing Use of Growth-friendly Implants for Early-onset Scoliosis: A 10-Year Update

Abstract

Background: Growth-friendly treatment of early-onset scoliosis (EOS) has changed with the development and evolution of multiple devices. This study was designed to characterize changes in the use of growth-friendly implants for EOS from 2007 to 2017. Methods: We queried the Pediatric Spine Study Group database for patients who underwent index surgery with growth-friendly implants from July 2007 to June 2017. In 1298 patients, we assessed causes of EOS; preoperative curve magnitude; age at first surgery; patient sex; construct type; lengthening interval; incidence of “final” fusion for definitive treatment; and age at definitive treatment. α=0.05. Results: From 2007 to 2017, the annual proportion of patients with idiopathic EOS increased from 12% to 33% (R 2=0.58, P=0.006). Neuromuscular EOS was the most common type at all time points (range, 33% to 44%). By year, mean preoperative curve magnitude ranged from 67 to 77 degrees, with no significant temporal changes. Mean (±SD) age at first surgery increased from 6.1±2.9 years in 2007 to 7.8±2.5 years in 2017 (R 2=0.78, P<0.001). As a proportion of new implants, magnetically controlled growing rods increased from <5% during the first 2 years to 83% in the last 2 years of the study. Vertically expandable prosthetic titanium ribs decreased from a peak of 48% to 6%; growth-guidance devices decreased from 10% to 3%. No change was seen in mean surgical lengthening intervals (range, 6 to 9 mo) for the 614 patients with recorded lengthenings. Final fusion was performed in 88% of patients who had undergone definitive treatment, occurring at a mean age of 13.4±2.4 years. Conclusions: From 2007 to 2017, neuromuscular EOS was the most common diagnosis for patients treated with growth-friendly implants. Patient age at first surgery and the use of magnetically controlled growing rods increased during this time. Preoperative curve magnitude, traditional growing rod lengthening intervals, and rates of final fusion did not change. Level of Evidence: Level II.

Trends in the Utilization of Implants in Index Procedures for Early Onset Scoliosis From the Pediatric Spine Study Group

“…Our data mirrors and expands on that of Klyce et al,24 who reported on MCGR use within the PSSG from 2007 to 2017. Although use of the MCGR limits some of the issues with TGR and VEPTR, this device has higher initial implant costs and its own complication portfolio, which is similar in many ways to that of TGR and VEPTR.…”

Surgical Treatment of Pediatric Scoliosis: Historical Origins and Review of Current Techniques

“…Rods are lengthened in a physician’s office using a handheld magnetic device, which rotates an actuator within the rod and causes lengthening [ 62 , 63 ]. MGRs have grown significantly in popularity since their introduction, comprising < 5% of all growing rods in 2007–2008 and increasing to 83% in 2016–2017 [ 64 ].…”

Cost-Utility Analysis of Anterior Vertebral Body Tethering versus Spinal Fusion in Idiopathic Scoliosis from a US Integrated Healthcare Delivery System Perspective

“…However, the use of these technologies in recent studies has been limited to younger patient populations, [17][18][19][20][21][22][23][24][25][26][27][28][29][30][31] with current indications in the US limited to patients with early-onset scoliosis (<10 years of age), 32,33 and while these technologies allow fusion to be delayed until skeletal maturity is reached, a final fusion procedure is still required.…”