Magnetically Controlled Growing Rods Graduation: Lessons From a Single-center Series of 48 Patients

Abstract

Background: Magnetically controlled growing rod (MCGR) treatment for early-onset scoliosis (EOS) has become a widely utilized method of deformity control, but long-term follow-up reports are sparse. We evaluated the outcomes of a large group of consecutive pediatric patients diagnosed with EOS who were treated by MCGR to the endpoint of definitive spinal fusion in a single center. We hypothesized that lessons learned from treating a large volume of MCGR patients would lower the complication rate in comparison to what was previously reported by other studies. Methods: The records of 48 EOS patients with varied etiologies who were treated by MCGR between 2012 and 2022 and reached the end of treatment were analyzed retrospectively for baseline and final radiographic measurements and surgery-related complications. Results: The mean percent of improvement in the major coronal deformity was 51.7±25.0% and the mean T1 to T12 total growth was 52.9±21.9 mm. The total complication rate was 22.9% of which 12.5% required a single unplanned surgery, 6.3% required multiple unplanned surgeries, and 4% did not require any unplanned surgery. Conclusion: MCGR treatment provides adequate control of EOS, enabling satisfactory growth of the thoracic spine. The complication rate in a single large volume center is moderate. Level of Evidence: IV.

Radiological Outcomes of Magnetically Controlled Growing Rods for the Treatment of Children with Various Etiologies of Early-Onset Scoliosis—A Multicenter Study

“…This is important for constitutional growth, such as lung development and respiratory efficiency. The available literature regarding the growth rate of the T1–T12 segment of the spine is diverse, ranging from 1.5 to 13.2 mm/year [ 12 , 17 , 23 , 24 , 25 , 26 , 27 , 28 , 29 ]. The average T1–T12 increase during the observation period in our group of patients was 5.95 mm/year, which is similar to the values obtained by Subramanian et al [ 30 ] and Cheung et al [ 16 ].…”

“…Complications are estimated to range from 20% to 70–80% depending on the calculations in various reports. These reports may not fully reflect the actual values, as most of them were performed on a small number of patients [ 12 , 14 , 19 , 20 , 21 , 43 , 44 ]. A detailed analysis of complications will be the subject of future study and publication.…”

“…Patients qualified for revision surgery if they experienced an adverse event or complication that could not be treated conservatively, that threatened the safety and health of the patient, and that required prompt surgical intervention. Patients who were treated with MCGRs and experienced complications such as rod fracture and PJK development or reached the end of rod lengthening, skeletal maturity, or the minimum parameters T1–T12 and T1–S1 for conversion to PSF were operated electively [ 12 , 21 , 26 ]. In this study, we only noted the number of complications and the revision rate because all complications and unplanned surgeries have been analyzed very carefully in other studies.…”

“…In the surgical treatment of spinal deformities in children up to 10 years of age, various surgical techniques and implants are used to promote growth [ 7 , 8 , 9 , 10 , 11 ]. Developed in 2009, magnetically controlled growing rods (MCGRs) were intended to improve treatment and minimize the risk of complications, and especially to reduce the number of repeated surgeries and anesthesia performed to extend the instrumentation for standard growing rods [ 11 , 12 , 13 , 14 , 15 , 16 ]. The surgical technique itself is minimally invasive, requiring only two mini-incisions in the upper and lower spine, and the rods are attached submuscularly or subfascially to the spine using pedicle screws or hooks to connect the proximal and distal bases and placed rods [ 17 , 18 ].…”

“…After the initial surgery with the insertion of the MCGRs, rod distraction is performed without anesthesia, using only special equipment, i.e., an external remote control (ERC), without repeated operations. However, the procedure is not without its complications, with a significant risk of unplanned surgery, and concerns have been raised regarding the structural integrity of MCGR implants [ 12 , 14 , 19 , 20 , 21 ]. Most published studies looking at MCGR include small numbers of patients and short follow-up times.…”