Is Magnetically Controlled Growing Rod the Game Changer in Early-onset Scoliosis? A Preliminary Report

Minimally Invasive Controlled Growing Rods for the Surgical Treatment of Early-Onset Scoliosis-A Surgical Technique Video

BACKGROUND

Spinal deformities in children and adolescents can be easily divided into those occurring and diagnosed before the age of 10-early-onset scoliosis-and those occurring and diagnosed after the age of 10-late-onset scoliosis. When the curvature continues to progress and exceeds a Cobb angle of more than 60-65 degrees, surgical treatment should be considered. The most common treatment procedure for EOS is the surgical correction of the deformity using standard growing rods (SGRs), and in the case of congenital defects with additional hemivertebrae, it is the resection of the hemivertebra and short fusion. Minimally invasive controlled growing rods (MICGRs) need to be distracted every 6-9 months through a minimally invasive approach that involves sedation and neuromonitoring to obtain the best possible correction while minimizing complications. The aim of our study is to present a less-invasive surgical technique for MICGR implantation based on a two-case presentation-early-onset idiopathic scoliosis and congenital kyphosis. The surgical technique is the less-invasive percutaneous and subfascial implantation of MICGRs without long incisions in the back.

CONCLUSIONS

The use of MICGRs is an alternative and safe surgical technique for patients undergoing surgical treatment for EOS. Without the risk of metallosis, like in other implant systems, and the need for replacement after 2 years of use, like in using magnetically controlled growing rods (MCGRs), the MICGR system can be used as a less-invasive procedure, allowing for the avoidance of many periodic invasive procedures in children with a wider opening of the spine (like in using standard growing rods), minimizing the number of planned hospitalizations, reducing the length of hospital stays, and reducing the physical and mental burdens on young patients, parents, and families.

Predictors of Rod Length Gain and Sagittal Alignment Change After Magnetically Controlled Growing Rod Lengthening

STUDY DESIGN

This was a retrospective cohort study.

OBJECTIVE

There are preoperative characteristics that predict rod lengthening of magnetically controlled growing rods (MCGR). The lengthening of MCGR will lead to increased kyphosis.

SUMMARY OF BACKGROUND DATA

The amount of length gained by MCGR is variable, and predictors are lacking. Similarly, sagittal plane changes over the MCGR lengthening period have not been investigated.

MATERIALS AND METHODS

Patients with MCGR and a minimum 2-year follow-up were identified and those with previous spine surgery were excluded. Preimplantation, postimplantation, and last follow-up postlengthening radiographs were examined. Multiple linear regression analyses were used for rod length gain predictors.

RESULTS

Fifty-six patients with early-onset scoliosis met inclusion criteria: nine idiopathic, five congenital, 14 neuromuscular, 20 syndromic, and eight skeletal dysplasia patients. No difference was seen between subtypes of early-onset scoliosis for rod length gain ( P =0.62). Shorter preoperative T1-T12 height and higher curve correction rate after implantation were significant predictors for rod length gain ( P <0.001). Preoperative major curve magnitude and kyphosis were not significant predictors. Flattening of the spine around the actuator and compensative increase in T1-T5 kyphosis were seen secondarily after MCGR implantation. Maximum sagittal kyphosis, T1-T5 kyphosis, and T5-T12 kyphosis did not change during lengthening. Lumbar lordosis significantly decreased postimplantation (first erect) but then increased during lengthening. Pelvic incidence and sacral slope both increased during lengthening, but this may be age related.

CONCLUSION

Patients who gained the most rod length with MCGR were those with an initially shorter T1-T12 height and better initial curve correction at implantation, likely representing that implants work best in small patients with flexible curves. Diagnosis, preoperative curve magnitude, and thoracic kyphosis were not related to rod length gain. Thoracic kyphosis did not deteriorate over the lengthening phase.

LEVEL OF EVIDENCE

Level III-retrospective cohort study.

Clinical and radiographic evolution of graduate patients treated with magnetically controlled growing rods: results of a French multicentre study of 90 patients

PURPOSE

The purpose of this study was to investigate patients with early-onset scoliosis (EOS) who completed their electromagnetic lengthening rod program to assess the demographics of this population and to analyze the evolution of clinical and radiological parameters and the occurrence of complications.

METHODS

This was a multicenter study with 10 French centers. We collected all patients with EOS who had undergone electromagnetic lengthening between 2011 and 2022. They had to have reached the end of the procedure (graduate).

RESULTS

A total of 90 graduate patients were included. The mean follow-up time over the entire period was 66 months (25.3-109). Of these, only 66 patients (73.3%) underwent definitive spinal arthrodesis at the end of the lengthening phase, whereas 24 patients (26.7%) kept their hardware in situ with a mean follow-up time from the last lengthening of 25 months (3-68). Patients had an average of 2.6 surgeries (1-5) over the entire follow-up. Patients had an average of 7.9 lengthenings for a mean total lengthening of 26.9 mm (4-75). Analysis of the radiological parameters showed a percentage reduction in the main curve of 12 to 40%, depending on the etiology, with an average reduction of 73-44°, and an average thoracic height of 210 mm (171-214) for an average improvement of 31 mm (23-43). There was no significant difference in the sagittal parameters. During the lengthening phase, there were a total of 56 complications in 43 patients (43.9%; n = 56/98), of which 39 in 28 patients (28.6%) resulted in unplanned surgery. In the graduate patients, there were a total of 26 complications in 20 patients (22.2%), all of which resulted in unscheduled surgery.

CONCLUSION

MCGR, allow to decrease the number of surgeries, to progressively improve the scoliotic deformity and to reach a satisfactory thoracic height at the price of an important complication rate linked in particular to the complexity of the management of patients with an EOS.

LEVEL OF EVIDENCE II

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.

Autofusion With Magnetically Controlled Growing Rods: A Case Report

Magnetically controlled growing rods (MCGRs) are an effective alternative to traditional growing rods (TGRs) in the treatment of early-onset scoliosis (EOS), with comparable deformity correction despite fewer planned reoperations. This case report presents a unique case of autofusion in a patient with tetraplegic cerebral palsy, thoracic myelomeningocele, and EOS who was treated with dual MCGR instrumentation and underwent serial lengthening procedures for four years. We detail the operative and radiographic findings in a novel case of autofusion encountered after MCGR placement to treat EOS. An eight-year-old female with tetraplegic cerebral palsy causing a 94° right thoracic neuromuscular scoliosis was treated with dual MCGRs; she then underwent serial lengthenings every four months. At 12 years of age, during MCGR explantation and posterior spinal fusion, dense heterotopic autofusion was encountered around the MCGR instrumentation, limiting further deformity correction. The benefits of MCGRs make them an appealing alternative to TGRs for the treatment of EOS. Although the theoretical risk of autofusion in MCGRs is low, recent case reports propose autofusion as a possible reason for MCGRs' failure to lengthen.

Re-evaluating consensus and uncertainty among treatment options for early onset scoliosis: a 10-year update

PURPOSE

Consensus and uncertainty in early onset scoliosis (EOS) treatment were evaluated in 2010. It is currently unknown how treatment preferences have evolved over the past decade. The purpose of this study was to re-evaluate consensus and uncertainty among treatment options for EOS patients to understand how they compare to 10 years ago.

METHODS

11 pediatric spinal surgeons (similar participants as in 2010) were invited to complete a survey of 315 idiopathic and neuromuscular EOS cases (same cases as in 2010). Treatment options included the following: conservative management, distraction-based methods, growth guidance/modulation, and arthrodesis. Consensus was defined as ≥ 70% agreement, and uncertainty was < 70%. Associations between case characteristics and consensus for treatments were assessed via chi-squared and multiple regression analyses. Case characteristics associated with uncertainty were described.

RESULTS

Eleven surgeons [31.7 ± 7.8 years of experience] in the original 2010 cohort completed the survey. Consensus for conservative management was found in idiopathic patients aged ≤ 3, whereas in 2010, some of these cases were selected for surgery. There is currently consensus for casting idiopathic patients aged 1 or 2 with moderate curves, whereas in 2010, there was uncertainty between casting and bracing. Among neuromuscular cases with consensus for surgery, arthrodesis was chosen for patients aged 9 with larger curves.

CONCLUSION

Presently, preferences for conservative management have increased in comparison to 2010, and casting appears to be preferred over bracing in select infantile cases. Future research efforts with higher levels-of-evidence should be devoted to elucidate the areas of uncertainty to improve care in the EOS population.

LEVEL OF EVIDENCE

Level V.

Definitive fusions are better than growing rod procedures for juvenile patients with cerebral palsy and scoliosis: a prospective comparative cohort study

PURPOSE

This study compared the outcomes of juvenile patients with cerebral palsy (CP) and scoliosis who underwent spinal fusion (SF) versus growing rod (GR) surgery.

METHODS

Two prospective multicenter registries were queried for patients 8-10 years old with minimum 2-year follow-up who underwent SF or GR surgery (no MCGR). Demographics, radiographs, complications, and outcome scores were recorded.

RESULTS

There were 35 patients in the SF and 15 in the GR group. The mean age at surgery was 10 and 9.3 years in the SF and GR groups, respectively (p = 0.004). In the SF group preoperatively, the major curve measured 86° and 80° in the GR group (p = 0.40). "Definitive" surgery in the GR group consisted of SF in 10, implant retention in three, and implant removal in two. The SF group had 60.8% and the GR group had 45.0% correction following "definitive" surgery (p = 0.03). In the SF group, 8 patients and in the GR group, 9 patients (SF = 22.9%, GR = 60.0%) had a complication (p = 0.01). In the SF group, two patients (5.7%) had reoperations for infection; eight patients (53.3%) in the GR group had reoperations for infection and implant complications (p < 0.001). In the SF group, 23/30 parents (76.6%) noted that the child's life "improved a lot." In the GR group, 3/6 parents (50.0%) noted they were "neutral" about their child's ability to do things, 2/6 (33.3%) were "very dissatisfied."

CONCLUSIONS

SF treatment for juvenile patients with CP and scoliosis resulted in fewer complications and unplanned reoperations and better radiographic outcomes compared with GR. Quality of life improvements were also better in the SF group.

LEVEL OF EVIDENCE

Level III.

The Effect of Apical Vertebra Position on Growing Rod Treatment: A Clinical and Finite Element Study

BACKGROUND

Growing rods (GRs) is a commonly utilized technique for the management of early-onset scoliosis. The significance of the position of the apical vertebrae relative to the rods is not known. The purpose of this study is to analyze the potential effects of the position of the apical vertebrae in relation to the GRs on deformity control through plain radiographs and finite element analysis (FEA) modeling.

METHODS

We identified 140 patients treated with GR between 2000 and 2018. Patients who had a congenital vertebral anomaly or <2-year follow-up were excluded. Curve magnitude, traction radiograph under general anesthesia (TRUGA) flexibility, apical rotation, the lengths of T1-12, T1-S1, and the instrumented segments were recorded. Patients were divided into 3 groups according to the apical position on the postoperative radiographs: group 1 (both pedicles are between the rods), group 2 (convex rod is between the apical vertebra pedicles), group 3 (both pedicles are lateral to the convex rod). FEA models were created simulating the 3 groups. Both radiographic and FEA data were analyzed to compare the deformity control and growth in each group.

RESULTS

Fifty-eight patients were included in the final analyses (mean age 84 mo; range: 38 to 148). Ten patients (17%) were in group 1, 34 (59%) in group 2, and 14 (24%) in group 3. Difference between TRUGA flexibilities was statistically insignificant. Group 3 was the least successful in terms of both height gain and rotational control. FEA showed a decrease in rotation and displacement for every group, however, the residual rotation and displacement was highest in group 3.

CONCLUSIONS

Bringing the apex in line with the GR increases the capacity of growth preservation as it results in largest height gain and better deformity control. FEA model demonstrated that distraction alone is inadequate for controlling rotation, and with increasing apical translation, residual rotation after distraction also increases.

LEVEL OF EVIDENCE

Level III.

Outcomes of MCGR at > 3 year average follow-up in severe scoliosis: who undergoes elective revision vs UPROR?

PURPOSE

The purpose of this study was to evaluate mid-term outcomes of magnetically controlled growing rods (MCGR), evaluate factors associated with unplanned return to the operating room (UPROR) vs achieving full length. Full length was defined as achieving > 85% of the elongating portion of the rod.

METHODS

IRB approved retrospective single site study. 106 patients underwent MCGR between 2014 and 2020, 58 met inclusion criteria, all genders, ethnicities, and etiologies were included. Patients with < 1 year follow-up or previous instrumentation were excluded.

RESULTS

Follow-up averaged 43 months. 23 patients achieved full length 13 were revised to a new MCGR and 10 to a fusion; 5 were fused due to skeletal maturity; 12 were still lengthening; 2 were being observed; 16 experienced UPROR. Major curves improved from 80° (50-114) preoperative to 40° (7-78) at most recent follow-up or prior to revision, and 24° (4-57) after fusion. Fusion patients averaged 1.3 (1-4) procedures prior to fusion and gained 75 mm (38-142) in T1-S1 length. 16 patients experienced UPROR, 11 were male (p = 0.0238). All failures to elongate were male as was the rod fracture. Age was not correlated with UPROR (p = 0.318), but did correlate with implant-specific causes of UPROR. Specifically, anchor failure was associated with younger age and rod failure with older age at implantation (p = 0.013). There was no correlation between UPROR and major curve, flexibility or kyphosis.

CONCLUSION

This is the largest site study evaluating mid-term outcomes in MCGR patients. At > 3.5 year follow-up 47% were electively revised, 27% underwent UPROR, 26% were still lengthening, and 3% were being observed. UPROR was associated with male gender and age at implantation was associated with implant-related causes of UPROR. MCGR continues to have high complication rates, better knowledge of MCGR outcomes may improve patient education, surgical timing, and decision-making.

No Difference in the Rates of Unplanned Return to the Operating Room Between Magnetically Controlled Growing Rods and Traditional Growth Friendly Surgery for Children With Cerebral Palsy

BACKGROUND

Early-onset scoliosis (EOS) is common in children with cerebral palsy (CP). The effectiveness of magnetically controlled growing rods (MCGR) and the risk for unplanned return to the operating room (UPROR) remain to be studied in this patient population. The primary outcome of this study was to examine the frequency of UPROR between MCGRs as compared with traditional growth friendly (TGF) surgeries for children with EOS secondary to CP.

METHODS

Patients with EOS secondary to CP were prospectively identified from an international database, with data retrospectively analyzed. Scoliosis, kyphosis, T1-S1, and T1-T12 height were measured preoperation, immediate postoperation, and at minimum 2-year follow-up. The risk and etiology of UPRORs were compared between MCGR and TGF.

RESULTS

Of the 120 patients that met inclusion criteria, 86 received TGF (age 7.5±0. 1.8 y; mean follow-up 7.0±2.9 y) and 34 received MCGR (age 7.1±2.2 y, mean follow-up 2.8±0.0.5 y). Compared with TGF, MCGR resulted in significant improvements in maintenance of scoliosis (P=0.007). At final follow-up, UPRORs were 8 of 34 patients (24%) for MCGR and 37 of 86 patients (43%) for TGF (P=0.05). To minimize the influence of follow-up period, UPRORs within the first 2 years postoperation were evaluated: MCGR (7 of 34 patients, 21%) versus TGF (20 of 86 patients, 23%; P=0.75). Within the first 2 years, etiology of UPROR as a percentage of all patients per group were deep infection (13% TGF, 6% MCGR), implant failure/migration (12% TGF, 9% MCGR), dehiscence (4% TGF, 3% MCGR), and superficial infection (4% TGF, 3% MCGR). The most common etiology of UPROR for TGF was deep infection and for MCGR was implant failure/migration.

CONCLUSION

For patients with EOS secondary to CP, there was no difference in the risk of UPROR within the first 2 years postoperatively whether treated with TGF surgery or with MCGRs (23% TGF, 21% MCGR).

LEVEL OF EVIDENCE

Level III-retrospective cohort, therapeutic study.

How much does depth matter? Magnetically controlled growing rod distraction directly influenced by rod tissue depth

PURPOSE

Magnetically controlled growing rod (MCGR) for the treatment of early-onset scoliosis (EOS) is a relatively innovative technique. MCGR benefits over traditional growing rods are known but limitations and complications are being revealed. The purpose of this study was to examine the importance of tissue depth on rod lengthening.

METHODS

A single-institution retrospective review of 72 MCGR patients was performed. Ultrasound measured rod distraction. Differences in programmed and actual distraction, and complications were recorded. Tissue depths and achieved length were averaged and used to construct a regression to account for variability.

RESULTS

Percentage of std and offset orientation rod lengthening relative to the programmed distraction was inversely proportional to rod depth (std R = 0.50, p = 0.002) (offset R = 0.60, p < 0.001). Expected std rod lengthening achieved decreased by 1.46%/mm depth. Expected offset rod lengthening achieved decreased by 1.68%/mm depth. 28 pts (38.9%) sustained complications. Age, sex, BMI, standard tissue depth, and/or offset tissue depth had no predictive ability with respect to complications sustained (overall model R = 0.31, p = 0.36).

CONCLUSION

In a series of EOS surgical patients treated with MCGRs, the relationship between percentage of programmed lengthening achieved as well as total lengthening was inversely proportional to tissue depth of the rod. There was a trend towards increasing frequency of complications recorded with decreasing tissue depth though this was not significant. These data can help with surgical planning during MCGR placement.

Magnetically Controlled Growing Rods Graduation: Deformity Control with High Complication Rate

STUDY DESIGN

A multicenter retrospective review of consecutive series of patients.

OBJECTIVE

Long-term experience with using the magnetically controlled growing rods (MCGR) to treat patients with deformity in the growing spine to the conclusion of treatment with posterior spine fusion.

SUMMARY OF BACKGROUND DATA

MCGR treatment for growing spine gained popularity with paucity of long-term follow up data. We hypothesized that final fusion might be more effective in bringing additional correction of the spine deformity after treatment with MCGR than that reported after traditional growing rods (TGR) due to less scarring and auto-fusion.

METHODS

Retrospective review of 47 patients with varied etiology, treated between 2011 and 2017 which graduated treatment were followed in five academic medical centers for average of 50 months (range, 10-88).

RESULTS

The initial mean coronal deformity of 69.6° (95% CI 65-74) was corrected to 40° (95% CI 36-40) immediately after the MCGR implantation but progressed to 52.8° (95% CI 46-59) prior to the final surgery (P < 0.01). Nevertheless, thoracic spine growth (T1-T12 height) improved from 187.3 mm (95% CI 179-195) following index surgery to 208.9 mm (95% CI 199-218) prior to final fusion (P < 0.01). Significant correction and spinal length were obtained at final fusion, but metallosis was a frequent observation (47%, 22/47). The average growth rate was 0.5 mm/month (95% CI 0.3-0.6). The overall complication rate within our cohort was 66% (31/47) with 45% (21/47) of unplanned returns to the operating theater. 32% (15/47) of the patients had an implant related complication. Unplanned surgery was highly correlated with thoracic kyphosis greater than 40° (OR 5.42 95% CI 1.3-23).

CONCLUSION

Treatment of growing spine deformities with MCGR provides adequate control of spine deformity it is comparable to previously published data about TGR. The overall high complications rate over time and specifically implant related complications.Level of Evidence: 4.

The role of traditional growing rods in the era of magnetically controlled growing rods for the treatment of early-onset scoliosis

PURPOSE

To describe the clinical and radiographic profile of early-onset scoliosis (EOS) patients treated with traditional growing rods (TGR) during the magnetically-controlled growing rod (MCGR) era.

METHODS

A US multicenter EOS database was reviewed to identify (1) patients who underwent TGR after MCGR surgery was introduced at their institution, (2) patients who underwent MCGR during the same time period. Of 19 centers, 8 met criteria with all EOS etiologies represented. Clinical notes were reviewed to determine the indication for TGR. Patient demographics and pre-operative radiographs were compared between groups.

RESULTS

A total of 25 TGR and 127 MCGR patients were identified. The TGR patients were grouped by indication into the sagittal plane profile (n = 11), trunk height (n = 6), co-morbidities/need for MRI (n = 4), and other (ex: behavioral issues, remaining growth). Four patients had a combination of sagittal profile and short stature with sagittal profile listed as primary factor. The TGR short trunk group had a mean T1-S1 length of 192 mm vs 273 mm for the MCGR group (p = 0.0002). The TGR sagittal profile group, had a mean maximal kyphosis of 61° vs 55° for the MCGR group (p = 0.09).

CONCLUSION

TGR continues to have a role in the MCGR era. In this study, the most commonly reported indications for TGR were sagittal plane profile and trunk height. These results suggest that TGR is indicated in patients of short stature with stiff hyperkyphotic curves. As further experience is gained with MCGR, the indications for TGR will likely be refined.

Smaller Intervertebral Disc Volume and More Disc Degeneration after Spinal Distraction in Scoliotic Children

In recent decades, magnetically controlled growing rods (MCGR) were established to treat progressive early-onset scoliosis. The aim of this investigation was to assess the effect of long-term MCGR with continuous distraction on intervertebral discs in scoliotic children. Magnetic resonance imaging (MRI) of 33 children with spinal muscular atrophy was analyzed by grading intervertebral disc degeneration (IDD) and measuring intervertebral disc volume. Cohort I (n = 17) were children who had continuous spinal distraction with MCGRs for 5.1 years and MRI before (av. age 8.1) and after (av. age 13.4) MCGR treatment. Cohort II (n = 16, av. age 13.7) were patients without prior surgical treatment. Lumbar intervertebral disc volume of cohort I did not change during 5.1 years of MCGR treatment, whereas disc volumes were significantly larger in age- and disease-matched children without prior treatment (cohort II). Cohort I showed more IDD after MCGR treatment in comparison to early MRI studies of the same patients and children without surgical treatment. MRI data showed a volume reduction and disc degeneration of lower thoracic and lumbar intervertebral discs in scoliotic children after continuous spinal distraction with MCGRs. These effects were confirmed in the same subjects before and after treatment as well as in surgically untreated controls.

Comparison of Magnetically Controlled Growing Rods with Other Distraction-Based Surgical Technologies for Early-Onset Scoliosis: A Systematic Review and Meta-Analysis

BACKGROUND

Severe and progressive early-onset scoliosis (EOS) has a serious prognosis including cardiopulmonary compromise. Growth-friendly technologies are the current surgical standard of care. Magnetically controlled growing rods (MCGRs) are newer implants with the potential for better quality of life and cost savings; however, they have not been well compared with the traditional distraction-based implants. The objective of this study was to compare the surgical outcomes, complications, metal ion levels, quality-of-life outcomes, and cost of MCGRs with other distraction-based surgical technologies for the treatment of EOS.

METHODS

The MEDLINE, Embase, and Web of Science databases were searched. Record screening and data abstraction were completed in duplicate. Summary outcomes were calculated in a meta-analysis, if heterogeneity was appropriate, using a fixed-effects model.

RESULTS

This systematic review and meta-analysis included 18 studies. MCGRs were as clinically effective as other distraction-based technologies, with no significant difference in the Cobb angle at the latest follow-up (mean difference [MD], 1.20°; 95% confidence interval [CI], -1.80° to 4.20°; p = 0.43) and a significantly lower complication rate (odds ratio, 0.42; 95% CI, 0.25 to 0.71; p = 0.001). Quality of life measured using the EOSQ-24 (24-Item Early-Onset Scoliosis Questionnaire) was better in the MCGR group compared with other technologies (MD, 2.18; 95% CI, 0.40 to 3.95; p = 0.02). Serum titanium levels were 2.98 ng/mL (95% CI, 1.41 to 4.55 ng/mL; p = 0.0002) greater in patients with MCGRs, but the clinical impact is unclear. MCGRs had greater cost for the device and insertion but became cost-neutral or cost-effective compared with other technologies by 4 years postoperatively.

CONCLUSIONS

MCGRs are clinically equivalent and cost-effective in the long term compared with other distraction-based technologies for the treatment of EOS.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Current status of the magnetically controlled growing rod in treatment of early-onset scoliosis: What we know after a decade of experience

The magnetically controlled growing rod (MCGR) has had approximately 10 years of clinical experience worldwide. Clinical effectiveness to control early-onset scoliosis is consistent even at final surgery. MCGRs have significantly lower relative percentage of infection or wound complications as compared to traditional growing rods. Most common complications include foundation failure and failure of distraction. Contouring of the rod especially at the proximal segment while accommodating for the straight actuator remains a difficult task and its failure may lead to proximal junctional kyphosis. Unique complications of MCGR include clunking, temporary diminishing distraction gains, and metallosis. Temporary reductions in distraction gains are observed as the MCGR lengthens but return to normal baseline distraction gains after rod exchange. Lack of standardization for rod configuration, distraction strategies and decisions of whether to keep the rods in situ, remove without fusion surgery or to perform spinal fusion at skeletal maturity will require further study.

Clinical Issues for Pediatric Pulmonologists Managing Children With Thoracic Insufficiency Syndrome

Thoracic insufficiency Syndrome (TIS) is a recently coined phrase to describe children with spine and chest wall deformities, inherited and acquired, who have respiratory impairment, and are skeletally immature. This population has both restrictive and less often obstructive lung disease due to changes in spine and rib configuration which reduce lung volume, stiffen the chest wall, and reduce respiratory muscle strength. Although the population is heterogeneous with regard to age of onset, etiology, severity of deformity, and rate of progression of the deformity, there are common issues that arise which can be addressed by pediatric pulmonologists. These are illustrated in this review by using Early Onset Scoliosis as a common form of TIS. The pulmonary issues pertaining to TIS require collaboration with multi-disciplinary teams, particularly spine surgeons, in order to make decisions about non-surgical and surgical strategies, timing of surgery and medical supportive care over time. Pulmonary input about respiratory function should be used in conjunction with structural features of each deformity in order to determine the impact of the deformity and the response to various treatment options. In those patients with residual lung function impairment as young adults, pediatric pulmonologists must also ensure successful transition to adult care.

Health-related quality of life in early-onset-scoliosis patients treated with growth-friendly implants is influenced by etiology, complication rate and ambulatory ability

BACKGROUND

Progressive Early-Onset Scoliosis (EOS) in children may lead to surgical interventions with growth-friendly implants, which require repeated lengthening procedures in order to allow adequate growth. Quality of life was studied using the validated German version of the EOS-Questionnaire (EOSQ-24-G) in surgically treated EOS children with different lengthening modalities.

METHODS

EOSQ-24-G and the KINDLR questionnaire were given to families with EOS children who had been treated by either vertical expandable prosthetic titanium rib implants and repetitive lengthening surgeries every 6 months or children who had received a magnetically expansion controlled implant, which was externally lengthened every 3 months. Results were compared according to differences between the two tests, and with possible influencing factors such as surgical method, severity of scoliosis, relative improvement of curvature, etiology, weight, age, travelling distance, complications, ambulatory ability and others.

RESULTS

56 children with an average curve angle of 69° corrected to 33° (52%; average age 5.6 yrs) answered the EOSQ-24-G and the KINDLR after an average follow-up of 3.9 years. Health-related quality of life (HRQoL) was not affected by the initial scoliosis correction, the number of surgeries or the implant type. However, there was a negative correlation with non-ambulatory status, complications during treatment and for children with a neuromuscular scoliosis.

CONCLUSION

Using the validated EOSQ-24-G, no statistically significant differences were found between the group of children receiving repetitive surgeries and children with external lengthening procedures without surgery. However, results were influenced by the etiology, complication rate or ambulatory ability.

LEVEL OF EVIDENCE/CLINICAL RELEVANCE

Therapeutic Level IV.