Use of a distraction-to-stall lengthening procedure in magnetically controlled growing rods: A single-center cohort study

Less-Invasive Approach to Early-Onset Scoliosis—Surgical Technique for Magnetically Controlled Growing Rod (MCGR) Based on Treatment of 2-Year-Old Child with Severe Scoliosis

Background: Spinal deformities in children can be caused by various etiologies, such as congenital, syndromic, neuromuscular, or idiopathic. Early-onset scoliosis (EOS) is diagnosed before the age of ten years, and when the curvature continues to progress and exceeds a Cobb angle of 60–65 degrees, surgical treatment should be considered. Initial minimally invasive surgery and the implantation of magnetically controlled growing rods (MCGRs) allows for the noninvasive distraction of the spine, growing, and avoids multiple operations associated with the classic distractions of standard growing rods. Case presentation: A 2-year-old girl was admitted to our clinic with rapidly progressive thoracic scoliosis. The major curve of the thoracic spine Cobb angle was 122° at 30 months. No congenital deformities were detected. The surgical technique was the less-invasive percutaneous and subfascial implantation of MCGRs, without long incisions on the back and the non-invasive ambulatory lengthening of her spine over the next 4 years. Conclusions: MCGR is a safe procedure for EOS patients. It is extremely effective at correcting spinal deformity; controlling the growth and curvature of the spine as the child develops during growth; reducing the number of hospitalizations and anesthesia; and minimizing the physical and mental burden of young patients, parents, and their families.

Maintenance of curve correction and unplanned return to the operating room with magnetically controlled growing rods: a cohort of 24 patients with follow-up between 2 and 7 years

PURPOSE

Early onset scoliosis (EOS) is defined as spinal curvature affecting children below 10 years of age. Non-operative treatment can consist of casting and bracing. When curvature progresses despite these treatments, operative intervention is indicated. Traditional growing rods (TGR) have been a mainstay of treatment. Unfortunately, TGR's require planned return to the operating room every 6-9 months. Magnetic controlled growing rods (MCGR) ideally provide curve correction and allow the spine to grow without frequent surgeries. However, the ability to correct and maintain correction after MCGR has not been well-characterized. The purpose of this study is to evaluate maintenance of curve correction in patients treated primarily with MCGR and analyze the rate of complications including unplanned return to the operating room (UPROR).

METHODS

24 patients with EOS were retrospectively reviewed. These patients were subdivided into 4 subcategories: congenital, idiopathic, neuromuscular (NMS), and syndromic. The major curve correction (%) and T1-S1 distance were assessed utilizing scoliosis plain film radiographs over time. Complications and return to the operating room for any reason were recorded. Patients were followed until conversion to posterior spinal fusion (PSF) or most recent lengthening of MCGR.

RESULTS

There were 11 male and 13 female patients averaging 8 years at the time of index surgery. The average preoperative curve angle was 61.1°. Initial curve correction with MCGR obtained at the index procedure was 46.2%, reducing the mean curve angle to 32.7° (p < 0.05). Curve correction at a mean 6.2 years (2.4-7.4) follow-up was 36.1°, 40.9% curve correction. 75% of patients underwent conversion to PSF during the study period 4.8 years (2.4-7.0) after initial MCGR surgery. 15% of patients were still undergoing MCGR lengthening after 6.1 years. 54.2% of patients had at least one UPROR.

CONCLUSIONS

For patients with EOS with curve progression, MCGRs can maintain curve correction well after 2 years. Furthermore, MCGR allowed patients to grow over time to safely delay timing to definitive fusion. On average, patients underwent conversion to PSF after 4.7 years at an average age of 13.5. Although the complication rate in the first 2 years is relatively low, 54.2% of patients underwent an UPROR. As the use of MCGR increases, surgeons should be aware of possible complications associated with this technology and counsel patients accordingly. Further research is needed to continue to evaluate the efficacy and safety of MCGR in this challenging patient population.

Contraindications to magnetically controlled growing rods: consensus among experts in treating early onset scoliosis

PURPOSE

The purpose of this study was to describe contraindications to the magnetically controlled growing rod (MCGR) in patients with early onset scoliosis (EOS) by establishing consensus amongst expert surgeons who treat these patients frequently.

METHODS

Nine pediatric spine surgeons from an international EOS study group participated in semi-structured interviews via email to identify factors that influence decision making in the use of MCGR. A 39-question survey was then developed to specify these factors as contraindications for MCGR-these included patient age and size, etiology, medical comorbidities, coronal and sagittal curve profiles, and skin and soft tissue characteristics. Pediatric spine surgeons from the EOS international study group were invited to complete the survey. A second 29-item survey was created to determine details and clarify results from the first survey. Responses were analyzed for consensus (> 70%), near consensus (60-69%), and no consensus/variability (< 60%) for MCGR contraindication.

RESULTS

56 surgeons of 173 invited (32%) completed the first survey, and 64 (37%) completed the second survey. Responders had a mean of over 15 years in practice (range 1-45) with over 6 years of experience with using MCGR (range 2-12). 71.4% of respondents agreed that patient size characteristics should be considered as contraindications, including BMI (81.3%) and spinal height (84.4%), although a specific BMI range or a specific minimum spinal height were not agreed upon. Among surgeons who agreed that skin and soft tissue problems were contraindications (78.6%), insufficient soft tissue (98%) and skin (89%) to cover MCGR were specified. Among surgeons who reported curve stiffness as a contraindication (85.9%), there was agreement that this curve stiffness should be defined by clinical evaluation (78.2%) and by traction films (72.3%). Among surgeons who reported sagittal curve characteristics as contraindications, hyperkyphosis (95.3%) and sagittal curve apex above T3 (70%) were specified. Surgeons who indicated the need for repetitive MRI as a contraindication (79.7%) agreed that image quality (72.9%) and not patient safety (13.6%) was the concern. In the entire cohort, consensus was not achieved on the following factors: patient age (57.4%), medical comorbidities (46.4%), etiology (53.6%), and coronal curve characteristics (58.9%).

CONCLUSION

Surgeon consensus suggests that MCGR should be avoided in patients who have insufficient spinal height to accommodate the MCGR, have potential skin and soft tissue inadequacy, have too stiff a spinal curve, have too much kyphosis, and require repetitive MRI, particularly of the spine. Future data-driven studies using this framework are warranted to generate more specific criteria (e.g. specific degrees of kyphosis) to facilitate clinical decision making for EOS patients.

LEVEL OF EVIDENCE

Level V-expert opinion.

Longitudinal comparison of direct medical cost, radiological and health-related quality of life treatment outcomes between traditional growing rods and magnetically controlled growing rods from preoperative to maturity

Background

Magnetically controlled growing rods (MCGR) have replaced traditional growing rods (TGR) in the past decade, however, a comparison of their direct costs and treatment outcomes based on real longitudinal data is lacking. This study aims to compare the direct cost and treatment outcomes between TGR and MCGR, whilst incorporating complications, reoperations and changes in health-related quality of life (HRQoL) throughout the entire treatment course.

Methods

Patients with early onset scoliosis (EOS) who underwent initial growing rod surgery between 2003 and 2016 at a tertiary scoliosis clinic were studied with longitudinal data. Accumulated direct medical costs were calculated based on the unit cost of surgeries of each TGR and MCGR, costs incurred for any rod exchange or remedial surgery for post-operative complication. Treatment outcomes were evaluated via: Patient’s HRQoL using SRS-22r questionnaire, and radiological parameters (including major curve correction, spine length gains, spinal balance) throughout the treatment until maturity.

Results

A total of 27 EOS patients (16 MCGR, 11 TGR) were studied. Total direct cost of index surgery for MCGR was HKD$223,108 versus lower cost of HKD$135,184 for TGR (p < 0.001). At 2–3 years post-index surgery, accumulative total direct medical cost of MCGR and TGR became most comparable (TGR:MCGR ratio = 1.010) and had reached neutrality between the two groups since. Radiological parameters had no intergroup differences at maturity. For HRQoL, TGR group had shown the trend of less pain (domain score mean difference: 0.53, p = 0.024) post-index surgery and better self-appearance (domain score mean difference: 1.08, p = 0.017) before fusion. Higher satisfaction with treatment (domain score mean difference: 0.76, p = 0.029) was demonstrated by TGR patients at fusion/maturity. MCGR had negative (r_s = -0.693) versus TGR’s positive (r_s = 0.989) correlations (p < 0.05) of cost and SRS-22r total scores at 2–3 years post-index surgery.

Conclusions

From index surgery to maturity, TGR demonstrated better satisfaction with treatment by patients and comparable overall HRQoL with MCGR during the treatment course, as MCGR did not show apparent benefit despite less surgeries and cost neutrality between the two groups at 2–3 years post-index surgery.

Magnetically controlled growing rods in the management of early onset scoliosis: a systematic review

Background

Early onset scoliosis (EOS) presents in patients younger than 10 years. Magnetically controlled growing rods (MCGR) were developed as an outpatient distraction system for EOS, allowing to avoid multiple surgeries. This systematic review investigated the efficacy and feasibility of MCGR in EOS.

Methods

This systematic review was conducted according to the PRISMA guidelines. PubMed, Google scholar, Embase, and Scopus were accessed in May 2022. All the clinical trials which investigate the role of MCGR for early onset scoliosis were accessed. Only studies reporting data in patients younger than 10 years with a preoperative Cobb Angle greater than 40° were eligible. The following data was extracted at baseline and at last follow-up: mean kyphosis angle, overall mean Cobb angle, mean T1–S1 length. Data from complication were also collected.

Results

Data from 23 clinical studies (504 patients) were included in the present study. 56% (282 of 504) were females. The average length of the follow-up was 28.9 ± 16.0 months. The mean age of the patients was 8.7 ± 1.9 years old. The mean BMI was 17.7 ± 7.6 kg/m². The mean kyphosis angle had reduced by the last follow-up (P = 0.04), as did the overall mean Cobb angle (P < 0.0001), while the overall T1–S1 length increased (P = 0.0002). Implant-associated complications, followed by spinal alignment failure, wound healing ailments, pulmonary complications, progressive trunk stiffness, persistent back pain, and fracture.

Conclusion

The management of EOS remains challenging. The current evidence indicates that MCGR may be effective to distract the spine and model the curve in EOS.

Optimizing Expansion Clinic for Patients With Magnetic Controlled Growth Rods

In 2017, members of the Pediatric Spine Study Group reported that 80% of new growth-friendly implants inserted were magnetically controlled growing rods (MCGRs). MCGRs are usually expanded more often than every 6 months, as was general practice with traditional growth rods. The growing volume of expansion visits is managed variably at different centers. Although there is existing research comparing MCGRs with traditional systems for efficacy and complications, there is limited literature regarding how expansion clinics are managed. This article reviews current practices such as scheduling, expansion verification, billing, and other key parameters for running expansion clinics.

A biomechanical study on the effect of lengthening magnitude on spine off-loading in magnetically controlled growing rod surgery: Implications on lengthening frequency

Purpose: To assess whether the magnitude of lengthening in magnetically controlled growing rod (MCGR) surgeries has an immediate or delayed effect on spinal off-loading. Methods: 9 whole porcine spines were instrumented using two standard MCGRs from T9 to L5. Static compression testing using a mechanical testing system (MTS) was performed at three MCGR lengthening stages (0 mm, 2 mm, and 6 mm) in each spine. At each stage, five cycles of compression at 175N with 25 min of relaxation was carried out. Off-loading was derived by comparing the load sustained by the spine with force applied by the MTS to the spine. Micro-CT imaging was subsequently performed. Results: The mean load sustained by the vertebral body before lengthening was 39.69N, and immediately after lengthening was 25.12N and 19.91N at 2 mm and 6 mm lengthening, respectively; decreasing to 10.07N, 8.31N, and 8.17N after 25 minutes of relaxation, at 0 mm, 2 mm, and 6 mm lengthening stages, respectively. There was no significant difference in off-loading between 2 mm and 6 mm lengthening stages, either instantaneously (p = 0.395) or after viscoelastic relaxation (p = 0.958). CT images showed fractures/separations at the level of pedicle screws in six spines and in the vertebral body's growth zone in five spines after 6 mm MCGR lengthening. Conclusion: This study demonstrated MCGRs cause significant off-loading of the spine leading to stress shielding. 6 mm of lengthening caused tissue damage and microfractures in some spines. There was no significant difference in spine off-loading between 2 mm and 6 mm MCGR lengthening, either immediately after lengthening or after viscoelastic relaxation.

The first magnetically controlled growing rod (MCGR) in the world - lessons learned and how the identified complications helped to develop the implant in the past decade: case report

Background

The first magnetically controlled growing rod (MCGR) was implanted in 2009. Since then multiple complications have been identified that have helped drive the development of the MCGR and its surgery. The aim of this report is to illustrate how identified complications in the first MCGR helped with developments in the past decade and to report a unique failure mechanism with stud fracture close to the barrel opening.

Case presentation

A 5-year old girl with a scoliosis of 58.5 degrees at T1–9 and 72.8 degrees at T9-L4 had a single MCGR inserted and anchored at T3–4 and L3–4. At postoperative 13 months the MCGR was noted to have lost of distraction between lengthening episodes due to unrestricted turning of the internal magnet. To prevent further loss of distraction, an external magnet was placed outside the skin to prevent the magnet from turning back. The overall balance was suboptimal and after the rod was fully distracted, proximal junctional kyphosis occurred. Subsequently, the MCGR was modified with an internal keeper plate to prevent loss of distraction and a dual set of these rods were implanted when the patient was 9 years old. Extension proximally to C7-T1 was done to manage the proximal junctional kyphosis. Her spinal balance improved and distractions continued. She subsequently developed add-on below and the piston rod was not aligned with the actuator. The lumbar spine was also observed to have autofusion. She subsequently had final fusion surgery performed at the age of 15 from C7-L4 leaving a residual tilt below to avoid fusion to the pelvis. The final extracted rod on the left side indicated the “crooked rod sign” on X-ray and rod dissections revealed a new failure mechanism of stud fracture close to the barrel opening. Body fluids and tissue may infiltrate the rod despite no obvious deformation or fractures resulting in hastened wearing of the threads.

Conclusions

There are various complications associated with MCGRs that are related to rod design and surgical inexperience. Repeated rod stalling is not recommended with potential stud fracture and “crooked rod sign”. Rotor stalling and thread wearing which indicates rod failure still require solutions.

How frequent should the radiographic examination be to monitor magnetically controlled growing rods? A retrospective look two to seven years postoperatively

PURPOSE

Magnetically controlled growing rods (MCGR) allow more frequent outpatient lengthenings to better mimic the physiological growth. The assessment of distractions with radiographs raised concerns regarding ionizing radiation exposure in growing children. The aim was to assess the necessity of radiographs after every lengthening of MCGR.

METHODS

A retrospective analysis of 30 consecutive patients (19F, 11 M) treated in a single institution between 2011 and 2017. Planned radiographs were taken based on a protocol, updated over the years to involve less frequent acquisitions. Unplanned radiographs were obtained after a patient complaint or a significant clinical examination finding. Outcome measures were preoperative and postoperative radiographic measurements, and complications such as proximal and distal junctional kyphosis and failure, rod or actuator breakage, collapse of previously achieved height or failure to lengthen and worsening of deformity.

RESULTS

Mean age at surgery was 7.5 (4-11) years. Mean follow-up was 45 (24-84) months. Mean number of lengthenings and radiographs per patient were 14.4 (8-23), and 13.2 (5-46), respectively. Nine patients (30%) experienced a total of 13 mechanical complications. Almost all complications were detected in unplanned radiographs. The probability of detecting a mechanical complication was significantly lower (p < 0.00001) in planned radiographs.

CONCLUSIONS

Radiographs taken after routine lengthenings of MCGR are not likely to reveal any significant finding, since only 0.9% of planned radiographs displayed a mechanical complication. Exposing growing children to radiation with an intention of checking the MCGR device after every lengthening could not be justified. Obtaining post-lengthening radiographs with a decreased frequency and after a significant complaint or clinical finding may be considered.

Sonography of Magnetically Controlled Growing Rods: A Quality Initiative in the Creation of a Multidisciplinary Clinic

Objective:

The MAGEC (Magnetic Expansion Control) rods were introduced to a medical institution in 2015. The rod expansion procedures were initially evaluated with radiographs. The staff undertook a quality initiative to reduce radiation exposure by utilizing sonography.

Material and Methods:

The radiation dose for a typical visit was measured by examining DICOM imaging data, stored in PACS. Imaging visit time was determined from the difference between times of first radiograph/sonogram before distraction to last radiograph/sonogram after distraction.

Results:

The 21 patients (8 male, 13 female) were an average age of 11.4 ± 2.82 years (age at implant = 7.5 ± 1.94) when evaluated. The average length of time for a radiographic visit was 40.7 ± 20.7 minutes, whereas a sonography visit was 10.7 ± 3.7 minutes. Radiation dose per study visit prior to the introduction of the MAGEC clinic was 0.42 ± 0.39 mSv. Given an ideal patient schedule, the MAGEC clinic could reduce radiation dose by 1.3 to 2.5 mSv annually, with 95% confidence.

Conclusion:

This quality improvement study demonstrated a reduction in radiation exposure and imaging time. The added benefits were providing a successful multidisciplinary imaging clinic and creation of a new exam that aligned with the “ultrasound first” initiative.

Distraction-to-stall Versus Targeted Distraction in Magnetically Controlled Growing Rods

BACKGROUND

Consensus is lacking regarding the lengthening procedures in magnetically controlled growing rods (MCGR), and no studies have compared the outcome between different distraction principles. The purpose of the present study was to compare distraction-to-stall with targeted distraction and identify variables associated with achieved distraction.

METHODS

We performed a 2-center retrospective study of all children treated with MCGR from November 2013 to January 2019, having a minimum of 1-year follow-up and undergoing a minimum of 3 distractions. Exclusion criteria were single-rod constructs and conversion cases. In group 1 (21 patients), we used a distraction-to-stall (maximum force) principle where each rod was lengthened until the internal magnetic driver stopped (clunking). In group 2 (18 patients), we used a targeted distraction principle, where the desired distraction was entered the remote control before distraction. In both groups we aimed for maximal distraction and curve correction at index surgery. Achieved distraction was measured on calibrated radiographs and compared between the 2 groups using a linear mixed effects model. Univariate and multivariate analyses were performed to identify variables associated with achieved distraction within the first year.

RESULTS

Mean age at surgery was 9.5±2.0 years. Etiology of the deformity was congenital/structural (n=7), neuromuscular (n=9), syndromic (n=3), or idiopathic (n=20). Demographics and preoperative characteristics including spinal height (T1T12 and T1S1) did not differ significantly between the groups (P≥0.13). Time interval between distractions were mean 18 days (95% confidence interval: 10-25) shorter in group 1. Implant-related complications occurred in 10/39 patients, 5 in each group. We found no difference in achieved distraction between the groups in the linear mixed effects model. In the multivariate analysis, preoperative major curve angle was the only independent variable associated with achieved distraction.

CONCLUSIONS

In 2 comparable and consecutive cohorts of patients treated with MCGR, we found no difference in achieved distraction between a distraction-to-stall and a targeted distraction principle. Preoperative major curve angle was the only independent predictor of achieved distraction.

LEVEL OF EVIDENCE

Level III-retrospective comparative study.

Lengthening of magnetically controlled growing rods caused minimal pain in 25 children: pain assessment with FPS-R, NRS, and r-FLACC

STUDY DESIGN

Descriptive case series.

OBJECTIVE

The aim of the study is to investigate the pain associated with magnetically controlled growing rod (MCGR) lengthening procedures. MCGRs have gained popularity because they offer non-surgical lengthening procedures in early-onset scoliosis (EOS) instead of semi-annual open surgery elongations with traditional growing rods. Many aspects of MCGR treatment have been investigated, but pain in conjunction with distraction is only sparsely described in the literature.

METHODS

Pain intensity was assessed in 25 EOS patients before, during and after MCGR lengthening procedures in an outpatient setup. They underwent at least two (range 2-16) lengthening procedures prior to this study. The pain intensity was estimated using patient-reported Faces Pain Scale (FPS-R), caregiver-reported pain numeric rating scale (NRS), and NRS and revised Face, Legs, Activity, Cry, Consolability scale (r-FLACC) by two medically trained observers. The inter-rater reliability and correlation between instruments were analyzed.

RESULTS

23 of 25 EOS patients (8- to 16-year old) with mixed etiology were able to self-report pain. The average pain intensity was mild: median 1 (range 0-6) on all four instruments on a 0-to-10 scale. Afterward, 22/25 patients (88%) were completely pain free and the remaining 3 patients had a pain score of 1. MCGR stalling (i.e. clunking) was encountered in 14/25 (56%) of the patients without impact on the pain intensity.

CONCLUSIONS

The average maximum pain intensities during the lengthening procedures were mild and pain ceased within few minutes. The inter-rater reliability was good to excellent for NRS and r-FLACC, and there were high correlations between all the four pain instruments, indicating high criterion validity.

LEVEL OF EVIDENCE

Level IV, case series.

Magnetic Controlled Growth Rods in the Treatment of Scoliosis: Safety, Efficacy and Patient Selection

Early-onset scoliosis is defined as a spinal curvature greater than 10° in children prior to 10 years of age. Untreated EOS may lead to progressively severe spinal deformity, impaired pulmonary development, restrictive lung disease, and both increased morbidity and mortality. Limitations of established conservative treatments include inability to correct severe deformity, as well as challenges with compliance when casting and bracing is applied. In addition, surgical treatment in the form of traditional growing rods requires regular surgical lengthenings and is associated with complications inherent with repeated invasive procedures and exposure to general anesthesia. MAGEC is an evolving magnetically controlled growing rod system for the treatment of EOS. After initial implantation, lengthening is achieved non-invasively by using magnetic external remote control. MAGEC offers the potential to control moderate and severe EOS, while avoiding repeated surgical procedures and associated complications. In this review, we examine the results from clinical, radiological and explant studies following the use of MAGEC, in the context of other established and emerging treatments for EOS.

Spinal Lengthening With Magnetically Controlled Growing Rods: Data From the Largest Series of Explanted Devices

STUDY DESIGN

Laboratory analysis of explanted MAGnetic Expansion Control (MAGEC) rods.

OBJECTIVE

The aim of this study was to identify the in vivo lengthening of MAGEC rods.

SUMMARY OF BACKGROUND DATA

Little data is available regarding the lengthening achieved by MAGEC rods.

METHODS

Cases were identified from the largest series of independently analyzed explanted MAGEC rods. The in vivo growth of rods was determined by the distance between the first "growth mark" and the actuator. The instrumented spinal lengthening was calculated for each construct. Constructs were considered functional if all rods could lengthen with external remote controller activation and no rods were "telescoping".

RESULTS

Fifty-five MAGEC constructs (99 rods) from 53 patients treated at 10 centers were included. The mean age at insertion was 8.5 years with rods implanted a mean of 35 months. Sixty rods were suitable for analysis with mean lengthening 21.7 mm, 8.9 mm/year. Of these 60 rods, three were maximally distracted. Mean instrumented spinal lengthening for 38 suitable cases was 22.1 mm, 8.4 mm/year. This was positively correlated with the duration of implantation (r = 0.34, P = 0.04) but negatively with patient age at insertion (r = -0.35, P = 0.03). The rate of instrumented spinal lengthening was negatively correlated with duration of implantation (r = -0.47, P = 0.004). Of 55 constructs, 34 were nonfunctional at time of removal with nine functional and 12 indeterminate. Functional constructs had been implanted significantly less time (20.0 vs. 39.7 months, P < 0.001) and lengthened less than those nonfunctional (12.3 mm vs. 23.3 mm, P = 0.04).

CONCLUSION

This multicenter explant study represents the largest cohort managed with MAGEC rods reported. Rods are very rarely removed having fully lengthened with mean instrumented spinal growth of 22 mm over the implant's life. This may be explained by a high rate of lengthening mechanism failure in received rods after around 3 years in vivo. Our findings question the effectiveness of the MAGEC system and mandate urgent comparative clinical studies.

LEVEL OF EVIDENCE

4.

Minimum 2-Year Experience with Magnetically Controlled Growing Rods for the Treatment of Early-Onset Scoliosis: A Systematic Review

Magnetically controlled growing rods have been used to treat early-onset scoliosis for the last 9 years; however, few studies have been published, with only short-term follow-up. The aim of the present study is to systematically review the outcomes of magnetically controlled growing rods in the treatment of early-onset scoliosis with a minimum of 2-year follow-up. Studies were included if patients with early-onset scoliosis (scoliosis diagnosed before 10 years of age) underwent implantation of magnetically controlled growing rods with a minimum of 2-year follow-up. The literature review and data extraction followed the established preferred reporting items for systematic review and meta-analysis guidelines. Data of distraction frequency, number of distractions, distracted length, Cobb angle, kyphosis, T1-T12 length, and T1-S1 length preoperatively, postoperatively, and at final follow-up were collected. Data regarding complications and unplanned reoperations were also extracted. The mean values of these parameters were calculated, or pooled meta-analysis was performed if available. Ten articles were included in this systematic review, with a total of 116 patients and a follow-up period between 23 and 61 months. The mean preoperative Cobb angle and kyphosis angle were 60.1° and 38.0°, respectively, and improved to 35.4° and 26.1° postoperatively. At final follow-up, the Cobb and kyphosis angles were maintained at 36.9° and 36.0°, respectively. The average preoperative T1-T12 and T1-S1 lengths were 180.6 mm and 293.6 mm, respectively, and increased to 198.3 mm and 320.3 mm postoperatively. T1-T12 and T1-S1 lengths were 212.3 mm and 339.3 mm at final follow-up, respectively. The overall rate of patients with complications was 48% (95% confidence interval [CI], 0.38-0.58) and unplanned reoperation 44% (95% CI, 0.33-0.55) after sensitivity analysis. The current evidence from different countries with a minimum of a 2-year follow-up suggests that magnetically controlled growing rods are an effective technique to treat pediatric scoliosis and promote spine growth. However, nearly half of patients still developed complications or required unplanned reoperations.