Avoidance of "Final" Surgical Fusion After Growing-Rod Treatment for Early-Onset Scoliosis

Outcome of distraction-based growing rods at graduation: a comparison of traditional growing rods and magnetically controlled growing rods

INTRODUCTION

Distraction-based growing rods have been considered as an alternative surgical option for the operative treatment of EOS. TGR has been challenged by MCGR, which is reported to have the advantage of non-invasive lengthening with fewer planned returns to theatre. This study explores the radiographic outcomes, Unplanned Returns to the Operating Room (UPROR) and complication profile of both the procedures at the end of the planned growing rod treatment with either TGR or MCGR.

METHODS

We included all the EOS cases from the PSSG database that underwent either TGR or MCGR with spine-based proximal anchors, followed up to the time of graduation. Any crossover or hybrid procedures were excluded. 549 patients (409 TGR and 140 MCGR) were eligible for review. We measured the coronal curve magnitude, Kyphosis, T1-T12, T1-S1 and L1-S1 lengths at 4 time points (before and after the index surgery and before and after the definitive surgery).

RESULTS

The TGR group were slightly younger at the time of the index procedure (7 years for TGR vs. 8.5 years for MCGR, p < 0.001). We noted an improvement in all radiological parameters after the growing rod implantation. The spinal lengths increased through the lengthening period, while the coronal curve magnitude and the kyphosis increased. The kyphosis normalized following the final fusion, the coronal curve magnitude reduced further with a further increase in spinal lengths. The final follow-up from the time of the index implantation to the definitive surgery was 5.1 years (IQR 3.8) in TGR and 3.5 years (IQR 1.65) in the MCGR groups. The total number of complications was fewer in the MCGR group. The overall risk of UPROR was lower in the MCGR group and implant breakage was less in the MCGR group by 4.7 times.

CONCLUSIONS

This study confirms the equivalence of both the distraction-based growing rods systems from the radiological stand-point, during the lengthening phase and at the time of the definitive surgery. The TGR was more kyphogenic during the lengthening period. The complications and UPROR were fewer in the MCGR groups.

Achievements and complications related to final fusion surgery in early onset scoliosis at the end of "traditional dual growing rod mission"

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

Assess the outcomes of final fusion in early onset scoliosis patients treated with TDGR, particularly with acceptable coronal and sagittal alignment at the end of their growing age. Early onset scoliosis (EOS) poses challenges due to the need for managing spinal deformities while accommodating trunk growth. The dual growing rod (TDGR) technique, a traditional approach, aims to address these concerns by periodic lengthening until spinal growth ceases. Recent shifts propose observation without immediate implant removal after achieving spinal alignment, raising questions about the necessity of final fusion surgery.

METHODS

This retrospective study included 22 EOS patients treated with TDGR who underwent final fusion surgery. Clinical and radiological data were analyzed, including pre- and post-surgery measurements, complications, surgical approaches, and screw density.

RESULTS

Patients (average initial surgery age: 6.9 years) exhibited significant reductions in main curve angle (preoperative: 65.8°, pre-fusion: 49.1°, post-fusion: 36.3°) and thoracic kyphosis (preoperative: 47°, pre-fusion: 46.6°, post-fusion: 38.7°). Complications included one surgical site infection and four transient intraoperative neuro-monitoring Impairment. High screw density correlated with lower total correction.

CONCLUSION

Final fusion surgery post-TDGR treatment shows promise in correcting EOS-associated deformities. Surgeons and parents should be aware of the procedure's complexity and potential complications.

Is Minimally Invasive Bipolar Technique a Better Alternative to Long Fusion for Adult Neuromuscular Scoliosis?

STUDY DESIGN

Prospective cohort study.

OBJECTIVES

To report the results for an alternative technique based on minimally invasive fusion-less surgery. This approach is original in that it corrects deformities by proximal and distal fixation, with reliable pelvic fixation through the use of iliosacral screws on osteoporotic bones.

METHODS

Adult cerebral palsy patients requiring spinal correction surgery were included prospectively between 2015 and 2019. The technique involved the use of a double-rod construct anchored proximally by four clawed hooks and distally by iliosacral screws, in a minimally invasive approach. Cobb angle and pelvic obliquity were measured before and after initial surgery and at final follow-up. Complications and functional results were reviewed. This group (P) was compared with a second group (R) of patients who underwent surgery between 2005 and 2015, for whom data were collected retrospectively.

RESULTS

Thirty-one patients were included in group P, and 15 in group R. The two groups were comparable for demographic data and deformity. At most recent follow-up (3 years for group P [2-6] and 5 years for group R [2-16]), neither correction nor surgical complications differed between the two groups. However, group P had 50% less blood loss and a lower medical complication rate than group R.

CONCLUSIONS

Our results confirm the effectiveness of this minimally invasive technique for neuromuscular scoliosis in adults. The results were similar to those obtained with the usual techniques, but with fewer medical complications. Confirmation of these results is now required for a longer follow-up period.

Defining the gaps in transitional care to adulthood for patients in paediatric surgical specialties: a scoping review protocol

INTRODUCTION

Transitioning patients from their paediatric centres to adulthood is an important subject for many of these patients living with different chronic pathologies. There are few studies that assess its effectiveness in paediatric surgical pathologies. The overall objective of this scoping review is to assess the extent of the literature describing transitional programmes dedicated to young patients living with surgical conditions. The primary question will look to assess what transitional programmes are available for young patients living with surgical conditions either operated or not.

METHODS AND ANALYSIS

The proposed scoping review will follow guidelines described by the Joanna Briggs Institute manual described by Peters et al in 2020. This protocol will employ the Preferred Reporting Items for Systematic review and Meta-Analysis Protocols checklist. The concept that will be included in this review is the exposure of these patients to a transition of care pathway or care programmes. Patients between the ages of 16 and 30 with a surgical condition will be included. There will be no comparator. No specific outcomes will be assessed, however, the outcomes that will be found from the transition programmes will be reviewed. A knowledge synthesis librarian will search MEDLINE All (Ovid), Embase (Ovid), Web of Science Core Collection (Clarivate) and CINAHL Complete (EBSCOhost). The literature search will be limited to 2000 onwards publications. No language or age group limitation will be applied. The reference list of all included sources of evidence will be screened for additional studies. Screening of search results and data extraction from included studies will be completed in Covidence by two independent reviewers. We will also use the PAGER (Patterns, Advances, Gaps, Evidence for practice and Research recommendations) framework to report and summarise the results.

ETHICS AND DISSEMINATION

This review does not require ethics approval. Our dissemination strategy includes peer review publication, conference presentation, co-constructed guidelines with stakeholders and policymakers.

TRIAL REGISTRATION

This review is registered on OSF.

Outcomes after completing growth-friendly surgical treatment for early-onset scoliosis in patients with skeletal dysplasia

Aims

The aim of this study was to compare outcomes after growth-friendly treatment for early-onset scoliosis (EOS) between patients with skeletal dysplasias versus those with other syndromes.

Methods

We retrospectively identified 20 patients with skeletal dysplasias and 292 with other syndromes (control group) who had completed surgical growth-friendly EOS treatment between 1 January 2000 and 31 December 2018. We compared radiological parameters, complications, and health-related quality of life (HRQoL) at mean follow-up of 8.6 years (SD 3.3) in the dysplasia group and 6.6 years (SD 2.6) in the control group.

Results

Mean major curve correction per patient did not differ significantly between the dysplasia group (43%) and the control group (28%; p = 0.087). Mean annual spinal height increase was less in the dysplasia group (9.3 mm (SD 5.1) than in the control group (16 mm (SD 9.2); p < 0.001). Mean annual spinal growth adjusted to patient preoperative standing height during the distraction period was 11% in the dysplasia group and 14% in the control group (p = 0.070). The complication rate was 1.6 times higher (95% confidence interval (CI) 1.3 to 2.0) in the dysplasia group. The following complications were more frequent in the dysplasia group: neurological injury (rate ratio (RR) 5.1 (95% CI 2.3 to 11)), deep surgical site infection (RR 2.2 (95% CI 1.2 to 4.1)), implant-related complications (RR 2.0 (95% CI 1.5 to 2.7)), and unplanned revision (RR 1.8 (95% CI 1.3 to 2.5)). Final fusion did not provide additional spinal height compared with watchful waiting (p = 0.054). There were no significant differences in HRQoL scores between the groups.

Conclusion

After growth-friendly EOS treatment, patients with skeletal dysplasias experienced a higher incidence of complications compared to those with other syndromes. Surgical growth-friendly treatment for skeletal dysplasia-associated EOS should be reserved for patients with severe, progressive deformities that are refractory to nonoperative treatment.

Is posterior vertebral arthrodesis at the end of the electromagnetic rod lengthening program necessary for all patients? Comparative analysis of sixty six patients who underwent definitive spinal arthrodesis and twenty four patients with in situ lengthening rods

PURPOSE

Magnetically controlled growing rods (MCGR) should be removed or changed at most two years after their implantation in the treatment of patients with early-onset scoliosis (EOS) (Safety notice July 2021). However, in the face of patients at high risk of intraoperative complications and relying on the principle of auto-fusion of the spine, some surgeons would prefer a more wait-and-see attitude. The aim of this study was to report on patients who did not undergo final fusion at the end of the lengthening program with MCGR and to compare them with those who did.

METHODS

This was a multicenter study with ten centres. We collected all graduate patients with EOS who had received MCGR between 2011 and 2022.

RESULTS

A total of 66 patients had final fusion at the end of the lengthening program and 24 patients kept MCGRs in situ. The mean total follow-up time was 66 months (range, 25.3-109), and the mean follow-up time after final lengthening was 24.9 months (range, 3-67.7). Regarding the main curve and thoracic height, there was no significant difference in the percentage of correction over the whole follow-up between the two groups (p = 0.099, p = 0.176) although there was a significant difference between the end of lengthening and the last follow-up (p < 0.001). After completion of the lengthening program, 18 patients who had final fusion developed 24 of the 26 recorded complications (92.3%).

CONCLUSION

Contrary to the manufacturer's published safety notice, not all patients systematically benefited from the removal of the MCGRs. Although arthrodesis significantly improved the scoliotic deformity, no significant difference was found in terms of radiographic outcome between patients who underwent spinal fusion and those who kept the MCGRs in situ.

Autofusion in growing rod surgery for early onset scoliosis; what do we know so far?

The evolving landscape of early onset scoliosis management has shifted from the traditional paradigm of early definitive spinal fusion towards modern growth-friendly implants, particularly Growing Rods (GR). Despite the initial classification of GR treatment as a fusionless procedure, the phenomenon of autofusion has emerged as a critical consideration in understanding its outcomes. Studies have demonstrated the presence of autofusion since the early 1980s. The consequences of autofusion are extensive, impacting curve correction, diminishing trunk growth rate, and contributing to the "law of diminishing returns" in growing rod surgery. The literature suggests that autofusion may complicate definitive fusion surgery, leading to prolonged and intricate procedures involving multiple osteotomies. Additionally, it poses challenges in identifying anatomical landmarks during surgery, potentially increasing the risk of complications and revisions. While autofusion poses challenges to achieving optimal outcomes in growing rod treatment, it cannot be considered a standalone replacement for definitive fusion. Recent advances aim to limit autofusion and enhance treatment outcomes. In this review, we will delve into the existing literature on autofusion, examining studies that have documented its presence, probable causes, pathophysiology, potential implications for long-term patient outcomes, and possible new implants and techniques that decrease its incidence.

Dual Growing Rods and the Apical Control Technique for Treating Congenital Early-Onset Scoliosis: Lessons Learned

BACKGROUND

Congenital early-onset scoliosis (CEOS) is characterized by a spectrum of vertebral anomalies, including formation failures and segmentation failures at the apex segment, which makes CEOS different from other etiologies of early-onset scoliosis. To date, studies on patients who have graduated from CEOS treatment using traditional dual growing rods (TDGR) have been scarce, and the preliminary results of TDGR with or without the apical control technique (ACT) have varied. We therefore compared the final outcomes of patients with CEOS who graduated from TDGR with or without the ACT.

METHODS

A retrospective study of patients with CEOS who had graduated from TDGR treatment performed from 2007 to 2020 was conducted. Graduation included final fusion or observation after reaching skeletal maturity. Patients were divided into the ACT-TDGR group (apical vertebrectomy and/or hemivertebrectomy with short fusion and TDGR) and the TDGR-only group. Demographic characteristics, radiographic data, patient-reported clinical outcomes, pulmonary function, and complications were analyzed.

RESULTS

A total of 41 patients with CEOS were enrolled: 13 in the ACT-TDGR group and 28 in the TDGR-only group. The lengthening intervals were longer in the ACT-TDGR group (mean [and standard deviation], 1.26 ± 0.66 years) than in the TDGR-only group (0.80 ± 0.27 years). The preoperative main curve was larger in the ACT-TDGR group (80.53° ± 19.50°) than in the TDGR-only group (64.11° ± 17.50°). The residual curve was comparable between groups (26.31° ± 12.82° in the ACT-TDGR group compared with 27.76° ± 15.0° in the TDGR group) at the latest follow-up. The changes in apical vertebral rotation and thoracic rotation were significantly larger in the ACT-TDGR group. Patients had comparable T1-12 and T1-S1 heights, pulmonary function, and 22-item Scoliosis Research Society (SRS-22) scores at the latest follow-up. The mean number of mechanical-related complications per patient was lower in the ACT-TDGR group (0.77 ± 0.73) than in the TDGR-only group (1.54 ± 1.43). Seventeen patients underwent final fusion.

CONCLUSIONS

In this small-scale study, we observed that both ACT-TDGR and TDGR-only could correct the deformity while allowing for spinal growth in patients with CEOS. ACT-TDGR yielded better correction in severe cases and did not have a deleterious effect on spinal height. A large number of cases will be needed to validate the clinical value of the ACT.

LEVEL OF EVIDENCE

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

The Minimally Invasive Bipolar Fixation for Pediatric Spinal Deformities: A Narrative Review

Growing rod techniques are increasingly used for early-onset scoliosis in children. Unfortunately, they are associated with many complications, particularly neuromuscular scoliosis, favored by the poor general condition of these patients and the fragility of their osteoporotic bones. Furthermore, these interventions are often iterative and usually followed by vertebral fusion at the end of growth. This is a review of the literature on a recent fusionless technique, minimally invasive bipolar fixation, which is more stable than the traditional growing rod techniques and less aggressive than vertebral arthrodesis. It allows the avoidance of arthrodesis, owing to the solidity of the construct and the stability of the results, leading to progressive spinal stiffening that occurs over time. The results of this technique have been published with a long follow-up period and have confirmed that it can completely replace posterior vertebral arthrodesis, especially in the most complicated scoliosis. Because it preserves growth, this technique should be recommended for early-onset scoliosis before the age of 10 years. The use of a self-expanding rod can avoid the need for repeated surgery, thereby reducing the risk of complications and the overall cost of treatment.

Clinical and radiological results of final fusion in patients who underwent lengthening with magnetically controlled growing rods. About 66 patients with a mean follow-up of 5 years

PURPOSE

The aim of this study was to evaluate the effects of definitive arthrodesis on frontal and sagittal spine balance in EOS patients treated with MCGR, as well as the complications associated with this procedure and the outcome at last follow-up.

METHODS

This was a multicentre study in 10 French centres. All patients who underwent posterior spinal arthrodesis after completion of MCGR treatment, regardless of age, etiology of scoliosis between 2011 and 2022, were included.

RESULTS

A total of 66 patients who had a final fusion after the lengthening programme were included in the study. The mean follow-up time was 5.5 ± 1.7 years (range: 2.1-9). The mean follow-up time after arthrodesis was 24 ± 18 months (range: 3-68) and the mean age at arthrodesis was 13.5 ± 1.5 years (range: 9.5-17). The main and secondary curves were significantly (p < 0.005 and p = 0.03) improved by arthrodesis (16.4° and 9° respectively) and stabilised at the last follow-up. The T1-T12 and T1-S1 distances increased by 8.4 mm and 14 mm with spinal fusion, with no significant difference (p = 0.096 and p = 0.068). There was no significant improvement in the rest of the parameters with arthrodesis, nor was there any significant deterioration at last follow-up. After final fusion, there were a total of 24 complications in 18 patients (27.3%) that routinely led to repeat surgery.

CONCLUSION

Final fusion after MCGR provides satisfactory additional correction of the main and secondary curves and a moderate increase in the T1-T12 distance but has no impact on sagittal balance and other radiological parameters. The post-operative complication rate is particularly high in patients at risk of complications.

LEVEL OF EVIDENCE

Level 4.

Traditional Dual Growing Rods With 2 Different Apical Control Techniques in the Treatment of Early-Onset Scoliosis

OBJECTIVE

Based on traditional dual growing rods (TDGR), apical control techniques (ACTs) were introduced as adjuvant procedures to improve deformity correction at the apex segment in the treatment of early-onset scoliosis (EOS). We aimed to explore whether TDGR+ ACTs have different indications, attain more deformity correction, have negative effects on spinal growth, and have different complications.

METHODS

Between 2004 and 2019, a retrospective study of EOS patients treated with TDGR with or without ACTs was conducted and divided into 3 groups: TDGR group; hybrid technique (HT) group: Vertebrectomy/hemivertebrectomy with short fusion and TDGR; ACPS group: apical convex control pedicle screws (ACPS) and TDGR. Demographic, radiographic parameters, clinical outcomes, complications, and revisions were analyzed and compared.

RESULTS

Seventy-eight EOS patients were enrolled. The preoperative main curve was the largest in the HT group. ACPS group had the smallest residual curve (19° ± 8.9°) and apical vertebral translation (12.0 ± 9.0 mm) at the latest follow-up, followed by the HT group (30° ± 17.4°, 22.1 ± 13.4 mm) and TDGR group (30° ± 13.2°, 32.8 ± 17.1 mm). ACPS group had the largest T1-12 height and T1-S1 height after index surgery. Complications and revisions in the ACTs groups was lower than the TDGR group. Scoliosis Research Society-22 self-image questionnaire was superior in the ACPS group.

CONCLUSION

According to our intermediate results, TDGR+ACTs could improve correction ability of apex deformity. ACTs had little deleterious effects on spinal height during the lengthening procedures, with a lower complication rate than TDGR. TDGR+ACTs might be a supplemental option for suitable EOS patients.

Growing rods in Early Onset Scoliosis: The current scenario

Background and aims

The treatment of early onset scoliosis is a challenge. Some curves resolve spontaneously, while the more aggressive ones require surgical intervention. Several surgical strategies have been explored in this unique group of patients, though the distraction based growing rods are the mainstay of treatment. The aim of this paper is to consider the current scenario with the surgical treatment for early onset scoliosis with growing rods.

Methods

This is a narrative review that explores the various types of growing rod options that are currently available. The results, as reported in literature, are discussed. The complications and problems with the commonly used growing rods are explored, based on the reported literature and on retrieval analysis that we have published. We discuss some of the newer modifications of growing rods.

Results

There is no real consensus on the ideal timing for the surgery or ways to assess the outcomes of the treatment. The Cobb angle measurement and measures of thoracic growth are surrogate markers. The main indication for surgery is to an increase in the thoracic dimensions and allowing for lung growth. Measures that are linked to lung function are more useful. We report some newer MRI scanning technology. Distraction-based growing rods have been reported to produce consistent and good results. Frequent return to theatre with the Traditional Growing Rods (TGR) and the metallosis related problems with the MCGR are reported.

Conclusions

We have learned a lot from the TGR and MCGR experiences. There is a scope for ongoing research to improve the design of the implant systems and better assess the outcomes on lung function. This review outlines these and helps identify the future trends.

A Comparative Analysis of Revision Surgery Before or After 2 Years After Graduation From Growth-friendly Surgery for Early Onset Scoliosis

INTRODUCTION

After discontinuation of growth-friendly (GF) surgery for early onset scoliosis, patients are termed graduates: they undergo a spinal fusion, are observed after final lengthening with GF implant maintenance, or are observed after GF implant removal. The purpose of this study was to compare the rates of and reasons for revision surgery in two cohorts of GF graduates: before or after 2 years of follow-up from graduation.

METHODS

A pediatric spine registry was queried for patients who underwent GF spine surgery with a minimum of 2 years of follow-ups after graduation by clinical and/or radiographic evidence. Scoliosis etiology, graduation strategy, number of, and reasons for revision surgery were queried.

RESULTS

There were 834 patients with a minimum of 2-year follow-up after graduation who were analyzed. There were 241 (29%) congenital, 271 (33%) neuromuscular, 168 (20%) syndromic, and 154 (18%) idiopathic. 803 (96%) had traditional growing rod/vertical expandable titanium rib as their GF construct and 31 (4%) had magnetically controlled growing rod. Five hundred ninety-six patients (71%) underwent spinal fusion at graduation, 208 (25%) had GF implants retained, and 30 (4%) had GF implants removed.In the entire cohort, there were 108/834 (13%) patients who underwent revision surgery. Of the revisions, 71/108 (66%) occurred as acute revisions (ARs) between 0 and 2 years from graduation (mean 0.6 y), and the most common AR indication was infection (26/71, 37%). The remaining 37/108 (34%) patients underwent delayed revision (DR) surgery >2 years (mean 3.8 y) from graduation, and the most common DR indication was implant issues (17/37, 46%).Graduation strategy affected revision rates. Of the 596 patients with spinal fusion as a graduation strategy, 98/596 (16%) underwent revision, compared with only 8/208 (4%) patients who had their GF implants retained, and 2/30 (7%) that had their GF implants removed (P ≤ 0.001).A significantly higher percentage of the ARs had a spinal fusion as the graduation strategy (68/71, 96%) compared with 30/37 DRs, (81%, P = 0.015). In addition, the 71 patients who underwent AR undergo more revision surgeries (mean: 2, range: 1 to 7) than 37 patients who underwent DR (mean: 1, range: 1 to 2) (P = 0.001).

CONCLUSION

In this largest reported series of GF graduates to date, the overall risk of revision was 13%. Patients who undergo a revision at any time, as well as ARs in particular, are more likely to have a spinal fusion as their graduation strategy. Patients who underwent AR, on average, undergo more revision surgeries than patients who underwent DR.

LEVEL OF EVIDENCE

Level III, comparative.

Benefits of fixing 3 proximal vertebral bodies vs. 2 in the treatment of early-onset scoliosis with growing rods

Additional proximal fixation for growing rods in early-onset scoliosis (EOS) may offer a more effective and safer option for severe scoliosis patients with hyper-kyphosis. Here, we compared the outcomes of EOS patients treated with growing rods in which 6 proximal anchor points on 3 vertebrae were used vs. 4 proximal anchor points on 2 vertebrae. The records of patients with EOS treated surgically from January 2016 to December 2017 were retrospectively reviewed. In the Proximal 4 group, 2 vertebral bodies were anchored proximally with 4 anchor points; in the Proximal 6 group, 3 vertebral bodies were anchored proximally with 6 anchor points. Forty-two patients (mean age 5.11 ± 1.93 years) were included; 22 Proximal 4 group, 20 Proximal 6 group. Mean follow-up was 40.86 ± 13.49 months. The decrease in main curve Cobb angle postoperatively was significantly greater in the Proximal 6 group (33.22° vs. 19.08°) ( P < 0.05). Cobb thoracic kyphosis (TK) was significantly decreased postoperatively in the Proximal 6 group (mean 20.70°); no significant decrease occurred in the Proximal 4 group. The main curve Cobb angle decrease at last follow-up was significantly greater in the Proximal 6 group (37.84° vs. 24.23°) ( P < 0.05). Cobb TK was significantly decreased at last follow-up in the Proximal 6 group (mean 25.17°, P < 0.05); no significant decrease occurred in the Proximal 4 group. Instrument complications were lower in the Proximal 6 group (15.00% vs. 45.45%) ( P < 0.05). No proximal junctional kyphosis was noted. Fixing 3 proximal vertebral bodies with 6 anchors improves radiographic outcomes of EOS treated with growing rods, and has a lower rate of screw pull-out.

Spontaneous induced bone fusion in minimally invasive fusionless bipolar fixation in neuromuscular scoliosis: a computed tomography analysis

PURPOSE

Posterior spinal fusion (PSF) at skeletal maturity is still the gold standard in children with neuromuscular scoliosis (NMS) who underwent fusionless surgery. The aim of this computed tomography (CT) study was to quantify the spontaneous bone fusion at the end of a lengthening program by minimally invasive fusionless bipolar fixation (MIFBF), that could avoid PSF.

METHODS

NMS operated on with MIFBF from T1 to the pelvis and at final lengthening program were included. CT was performed at least five years postoperatively. The autofusion was classified as completely or not fused at the facets joint (on both coronal and sagittal plane, right and left side, from T1 to L5), and around the rods (axial plane, right and left side, from T5 to L5). Vertebral body heights were assessed.

RESULTS

Ten patients were included (10.7y ± 2 at initial surgery). Mean Cobb angle was 82 ± 20 preoperatively and 37 ± 13 at last follow-up. CT were performed on average 6.7y ± 1.7 after initial surgery. Mean preoperative and last follow-up thoracic vertebrae height were respectively 13.5 mm ± 1.7 and 17.4 mm ± 1.7 (p < 0.001). 93% facets joints were fused (out of 320 analyzed joints), corresponding to 15/16 vertebral levels. Ossification around the rods was observed in 6.5±2.4 levels out of 13 in the convex side, and 4.2 ± 2.2 in the concave side (p = 0.04).

CONCLUSIONS

This first computed quantitative study showed MIFBF in NMS preserved spinal growth, while it induced 93% of facet joints fusion. This could be is an additional argument when questionning the real need for PSF at skeletal maturity.

Hybrid technique versus traditional dual growing rod technique to treat congenital early-onset scoliosis: a comparative study with more than 3 years of follow-up

OBJECTIVE

The authors' objective was to compare the intermediate outcomes of patients with severe congenital early-onset scoliosis (CEOS) treated with posterior vertebrectomy/hemivertebrectomy with short fusion and dual growing rods (hybrid technique [HT]) and those treated with traditional dual growing rods (TDGRs).

METHODS

A retrospective study of patients who underwent the HT and TDGR technique for CEOS was conducted. The inclusion criteria were CEOS (age < 10 years), Risser stage 0, treatment with HT or TDGR, index surgery performed between 2004 and 2017, and minimum follow-up of 3 years. For patients who completed lengthening procedures, the last lengthening procedure was considered the latest follow-up. Demographic, radiographic, clinical, and patient-reported outcomes and revisions were compared between groups.

RESULTS

Sixty-one patients with CEOS were included in this study, with 16 treated with HT and 45 with TDGR technique. There were no differences in age at index surgery, duration of treatment, or number of lengthening procedures. The lengthening interval was longer in the HT group. The preoperative mean ± SD main curve was 81.8° ± 17.1° for the HT group and 63.3° ± 16.9° for the TDGR group (p < 0.05). However, main curve correction was better in the HT group, and no differences in residual curve were found between groups. Although the preoperative apex vertebral translation (AVT) of the HT group was greater, the correction of AVT was better in the HT group (p < 0.05). No differences in T1-S1 and T1-12 height were found between groups at the latest follow-up. The growth of T1-S1 height was less in the HT group (p < 0.05), whereas the growth of T1-12 height was similar between groups. Patients in the HT group had a lower risk of mechanical complications but higher risks of dural tears and neurological complications.

CONCLUSIONS

HT may provide better correction and apex control ability than TDGR for EOS patients with severe and rigid deformity at the apex level, and it significantly decreased the risk of mechanical complications with little influence on growth of the thoracic spine. HT may be an option for patients with severe CEOS with large asymmetrical growth potential around the apex of the curve.

Is Final Fusion Necessary for Growing-Rod Graduates: A Systematic Review and Meta-Analysis

STUDY DESIGN

Systematic review and meta-analysis.

OBJECTIVES

The need for definitive fusion for growing rod graduates is a controversial topic in the management of Early-onset scoliosis (EOS) patients. The authors performed a systematic review and meta-analysis on the available literature to evaluate the outcomes of growing rod graduates undergoing final fusion or observation with implants in-situ.

METHODS

An extensive literature search was carried out aimed at identifying articles reporting outcomes in growing rod graduates. Apart from the study characteristics and demographic details, the extracted data included Cobb's correction, trunk height parameters, and revision rate. The extracted data was analyzed and forest plots were generated to draw comparisons between the observation and fusion groups.

RESULTS

Of the 11 included studies, 6 were case-control and 5 were case series. The authors did not find any significant difference between the 2 groups with respect to the pre-index and final Cobb's correction, T1-T12 or T1-S1 height gain in either over-all, or sub-analysis with case-control studies. The meta-analysis showed a significantly higher revision rate in patients undergoing a definitive fusion procedure.

CONCLUSION

The current analysis revealed comparable outcomes in terms of correction rate and gain in the trunk height but a lesser need of revisions in observation sub-group. The lack of good quality evidence and the need for prospective and randomized trials was also propounded by this review.

Matched Comparison of Magnetically Controlled Growing Rods with Traditional Growing Rods in Severe Early-Onset Scoliosis of ≥90°: An Interim Report on Outcomes 2 Years After Treatment

BACKGROUND

Severe early-onset scoliosis (EOS) is managed surgically but represents a challenge due to limited implant fixation points, large curve size, and fragile patients with comorbidities. Magnetically controlled growing rods (MCGRs) have the advantage of avoiding surgical intervention for routine lengthening, but their ability to address severe EOS has not been studied, to our knowledge.

METHODS

A retrospective review of a prospectively collected international database identified 44 children with severe (≥90°) EOS treated with MCGRs who met our study criteria. Etiology, age, and sex-matched patients treated with traditional growing rods (TGRs) were identified from the same database. Patients were evaluated at a 2-year follow-up. No patients with vertically expandable prosthetic titanium ribs (VEPTRs) were included. The health-related quality of life was evaluated with the 24-Item Early Onset Scoliosis Questionnaire (EOSQ-24).

RESULTS

The mean preoperative major coronal curve was 104° in the MCGR group and 104° in the TGR group. At the 2-year follow-up, the mean major coronal curves were 52° and 66° (p = 0.001), respectively. The mean T1-T12 heights were 155 mm and 152 mm preoperatively and 202 mm and 192 mm at the 2-year follow-up (p = 0.088). According to Kaplan-Meier analysis, the 2-year unplanned-revision-free survival was 91% in the MCGR group and 71% in the TGR group (p < 0.005). The 2-year score in the EOSQ-24 pulmonary function domain was better in the MCGR group. There were no other significant differences in the EOSQ-24 scores between the groups.

CONCLUSIONS

MCGRs for severe EOS provided significantly better major curve correction with significantly fewer unplanned revisions than TGRs at a 2-year follow-up.

LEVEL OF EVIDENCE

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

One-Way Self-Expanding Rod in Neuromuscular Scoliosis: Preliminary Results of a Prospective Series of 21 Patients

Fusionless techniques for the treatment of neuromuscular early-onset scoliosis (EOS) are increasingly used to preserve spinal and thoracic growth and to postpone posterior spinal fusion (PSF). These techniques have greatly improved thanks to magnetically controlled growing rods, which allow the avoidance of repeated surgery. However, the surgery-related complication rate remains high. The objective of the current study was to report the preliminary outcomes of 21 patients with neuromuscular EOS who were treated with a 1-way self-expanding rod (OWSER). This device was designed to avoid repeated surgery and preserve spinal and thoracic growth thanks to its free rod sliding.

Minimally Invasive Surgery for Neuromuscular Scoliosis: Results and Complications at a Minimal Follow-up of 5 Years

STUDY DESIGN

A prospective study.

OBJECTIVE

The aim of this study was to report the results of an alternative technique to growing rods (GR) for neuromuscular scoliosis using a minimally invasive fusionless surgery with a minimum of 5 years' follow-up.

SUMMARY OF BACKGROUND DATA

Conservative treatment is not effective in progressive neuromuscular scoliosis. Early surgery using GR is increasingly advocated to control the deformity while preserving spinal and thoracic growth before arthrodesis. These techniques still provide a high rate of complications.

METHODS

The technique relies on a bilateral double rod sliding instrumentation anchored proximally by four hooks claws and distally to the pelvis by iliosacral screws through a minimally invasive approach. The clinical and radiological outcomes of 100 consecutive patients with neuromuscular scoliosis who underwent this fusionless surgery with a minimum follow-up of 5 years were reviewed.

RESULTS

6.5 ± 0.7 years after initial surgery, six patients were lost of follow-up and 11 died of unrelated raison. Of the 83 remaining patients at latest follow-up, mean Cobb angle was stable to 35.0° which correspond to 61% correction of the initial deformation. Mean pelvic obliquity was 29.6° (0.3°-80.0°) preoperatively and 7.2 (0.2°-23.5°) at latest follow-up. Correction of the hyper kyphosis remained stable. Skeletal maturitywas reached in 42 of 83 patients (50.6%). None of these patients has required spinal fusion. The global complication rate was 31.3%.

CONCLUSION

The outcomes of this minimally invasive fusionless technique at 5 years follow-up showed a stable correction of spinal deformities and pelvic obliquity over time, with a reduced rate of complication. The arthrodesis was not required for all patients at skeletal maturity. This technique could be a good alternative to arthrodesis for neuromuscular scoliosis.Level of Evidence: 3.

Developments, Focuses, and Trends in Early-Onset Scoliosis From 2005 to 2020: A Systematic Bibliometric Analysis

OBJECTIVE

Although several studies have been reported on early-onset scoliosis (EOS), a bibliometric analysis is still lacking. A systematic bibliometric analysis will enable researchers to understand the scope of the research topics, identify research focuses and key literature, and predict future research directions.

METHODS

Literature data were retrieved from the Web of Science Core Collection database. The Web of Science Results Analysis and Citation Report were used to analyze the reported studies in different views. CiteSpace and VOSviewer were used for further analysis, including a cooperation network analysis of the authors, institutions, countries and/or regions, discipline and journal analysis, reference co-citation analysis, and keyword co-occurrence analysis.

RESULTS

The final analysis included 674 relevant studies reported from 2005 to 2020. During the study period, the field of EOS has expanded rapidly. Multiple cooperation was found among the authors, institutions, and countries and/or regions, with some making great contributions. The results of the reference co-citation analysis showed that the studies had several main focuses, including the growing rod (GR), magnetically controlled GR, an EOS 24-item questionnaire, and a growth evaluation.

CONCLUSIONS

From 2005 to 2020, surgical treatment has remained the focus of research in the EOS field. The magnetically controlled GR is the latest research focus, which might become more comprehensive in the future. The Gr has remained the most popular topic, and potential new surgical techniques might require improvement to become the favored techniques. In addition, assessing the health-related quality of life and growth parameters of patients with EOS have become a popular topic.

Clinical Outcomes of 3-column Osteotomy at Growing Rod Graduation

BACKGROUND

Several different strategies were described on how to graduate a patient when skeletal maturity is reached after growing rod treatment. A final instrumentation and fusion is commonly performed, but the stiffness of the spine after numerous lenghthenings can be a major problem. When correction is needed in a severe and rigid curve, 3-column osteotomies (3CO) can be used as a method of bringing the spine back to a well-balanced position. This study aims to evaluate the clinical outcomes of 3CO osteotomies at growing rod graduation.

METHODS

A retrospective search of the database was performed between 1996 and 2018. Inclusion criteria were: diagnosis of early-onset scoliosis, underwent 3CO at the final fusion procedure, and ≥1 year of follow-up. Indications for this osteotomy were: significant sagittal and/or coronal off-balance or severe crankshaft deformity or significant distal and/or proximal adding-on. Clinical, radiographic, and operative data were analyzed. Complications were classified according to the modified Clavien-Dindo-Sink system.

RESULTS

Eight patients were included in the study with a mean age of 13.5 at graduation (male/female: 2/6). The mean scoliosis angle significantly reduced from 65.6 to 39 degrees (P=0.012). Mean T1-T12 height increased from 19 to 20.5 (P=0.084) and T1-S1 from 29.6 to 31.6 (P=0.144). Five patients had a staged surgery. Average operative time was 338 minutes and blood loss was 1321 mL. Four grade 1, 1 grade 2, and 1 grade 3 complications occurred.

CONCLUSIONS

This is the first case-series in the literature reporting on the use of 3CO at growing rod graduation. These procedures can be safely and effectively used to overcome significant multiplanar deformity and/or off-balance in the graduation of patients with early-onset scoliosis and significant correction can be achieved on these severe and rigid curves.

LEVEL OF EVIDENCE

Level IV-case series.

Minimally Invasive Fusionless Surgery for Scoliosis in Spinal Muscular Atrophy: Long-term Follow-up Results in a Series of 59 Patients

BACKGROUND

Treatment of spinal muscular atrophy (SMA) scoliosis has evolved in the last decade, with the emergence of fusionless surgical techniques that allow correction of the deformity before the end of growth spurt. These techniques are expected to delay definitive spine fusion and preserve trunk growth.

PURPOSE

The aim was to evaluate long-term clinical, radiologic, and respiratory outcomes of a minimally invasive fusionless surgery (MIFLS) in SMA scoliosis.

METHODS

All children affected with SMA scoliosis who underwent MIFLS in our department from 2011 to 2019 were included. The instrumentation consisted in a bilateral sliding rod construct from T1 to the sacrum, anchored proximally by double-hook claws and distally by iliosacral screws. Clinical, genetic, respiratory and radiographic data were retrospectively reviewed. A patient's satisfaction survey was performed.

RESULTS

A total of 59 children with genetic confirmation of SMA (9SMA1c, 47SMA2, and 3SMA3) underwent MIFLS at a mean age of 11±1.9 years. All of them were nonwalker at the time of surgery. Twenty-six were treated with intrathecal Nusinersen. Mean follow-up was 5.2 years (2 to 9.6 y). Mean major coronal curve improved from 79±15 to 41±16 degrees and pelvic obliquity decreased from 24±11 to 5.9±4 degrees. Mean space available for lung improved from 77% to 93%. Mechanical or infectious complications occurred in 9 patients, with removal of the implant in 1. 6 children required unplanned surgeries. Postoperative bracing was needed in 13 children. Mean gain weight 3 years after the first surgery was 6 kg. 91.5% of patients had a positive satisfaction of the surgery. There was no significant impact in respiratory function postoperatively. Only 30 children required rod lengthening procedures, with a mean interval between procedures of 1.9 years (0.5 to 3.7 y). No arthrodesis was required at last follow-up in any patient.

CONCLUSION

Bipolar MIFLS in SMA preserves spinal and thoracic growth without interference with respiratory function. It provides a significant correction of spinal deformity and pelvic obliquity, having a reduced rate of complications. The correction of spinal deformity was maintained at long term, not requiring definitive fusion at the end of growth.

LEVEL OF EVIDENCE

Level IV.

Magnetically controlled growing rods in early onset scoliosis: radiological results, outcome, and complications in a series of 22 patients

INTRODUCTION

Magnetically controlled growing rods (MCGR) for the surgical treatment of early onset scoliosis (EOS) allow non-invasive outpatient based distractions during spinal growth. The purpose of this study is to present the results of a single center case series of 22 patients, evaluate the effect of MCGR treatment on the development of spino-pelvic parameters during growth, and report initial outcomes after end of treatment.

MATERIALS AND METHODS

Prospectively collected data of 22 EOS patients with MCGR treatment has been analyzed. The following radiological parameters were measured before index surgery, after index surgery, 1 year after index surgery, and at last follow-up: Cobb angle of the major curves, thoracic kyphosis (TK), lumbar lordosis (LL), sagittal vertical axis (SVA), pelvic incidence (PI), pelvic tilt (PT), and sacral slope (SS). Mean age at index surgery was 9.5 years (range: 4-14 years). Mean length of follow-up was 47.6 months (range: 25-121 months). Etiology of diagnosis was idiopathic in 14 patients, associated with neurofibromatosis in 2 patients, and neuromuscular or syndromic in 6 patients.

RESULTS

Mean Cobb angle of the major curve was 57° preoperatively and 29° at last follow-up (p < 0.0005). Mean TK was 20.1° preoperatively and 20° at last follow-up (p > 0.05). Mean LL was 52.8° preoperatively and 53.2° at last follow-up (p > 0.05). Mean PI was 43.2° preoperatively and 46.3° at last follow-up (p > 0.05). Mean PT was 4.1° preoperatively and 5.8° at last follow-up (p > 0.05). Mean SS was 39.2° preoperatively and 41.7° at last follow-up (p > 0.05). 14 patients finished treatment: nine received final fusion and five received rod removal without fusion. Twelve complications occurred: one deep wound infection, six patients developed proximal junctional kyphosis (PJK), one rod fracture, two rods failed to distract, one deformity progressed after rod removal and required spinal fusion, and one patient developed autofusion of the spine prior to end of treatment.

CONCLUSION

MCGR treatment is able to control deformity progression. Complication rate was 54.5%. Sagittal balance was not altered and treatment does not seem to have a negative impact on the development of spino-pelvic parameters during growth. Optimal end of treatment for the individual patient still has to be defined.

An initial effort to define an early onset scoliosis "graduate"-The Pediatric Spine Study Group experience

PURPOSE

Increasingly, patients with early onset scoliosis (EOS) are completing a growth friendly surgical program followed by observation, removal of implants or a definitive spinal fusion. These patients are colloquially referred to as "graduates". A standardized definition of a graduate is needed for research and comparing the outcomes, family counseling, and a better understanding of the population.

METHODS

A 15-question electronic survey was completed by 39 experienced pediatric spine surgeons to identify factors salient to the definition of a graduate of EOS surgical programs. A Delphi/Nominal group technique session with nine questions was then performed face-to-face with 21 members of the Pediatric Spine Study Group to discuss and refine the definition. A follow-up electronic survey was then distributed to these same 21 members to gain consensus on the final definition.

RESULTS

From the initial survey, it was identified that a graduate did not require definitive spinal fusion after a growing program. From the Delphi session, it was determined that skeletal maturity was the most important factor in defining a graduate. A strictly defined minimum length of follow-up was not felt to be a prerequisite for qualification of graduation. After the final electronic version was distributed, > 80% of respondents agreed upon the final definition, thereby achieving consensus.

CONCLUSION

The Pediatric Spine Study Group recommends adoption of the following definition: a "graduate" is a patient who has undergone any surgical program to treat early onset scoliosis, and has reached skeletal maturity and does not have a planned surgical intervention for EOS in the future.

LEVEL OF EVIDENCE

V.

Minimum 5-Year Follow-up on Graduates of Growing Spine Surgery for Early Onset Scoliosis

INTRODUCTION

After discontinuation of growth friendly (GF) surgery for early onset scoliosis, patients undergo spinal fusion or continued observation. This last planned treatment is colloquially called "definitive" treatment, conferring these patients as "graduates" of a growing program. The 5-year radiographic and clinical outcomes of this cohort are unknown.

METHODS

An international pediatric spine database was queried for patients from a GF program (spine or rib-based) with minimum 5-year follow-up from last planned surgery (GF or spinal fusion). Radiographs and charts were reviewed for main coronal curve angle and maximum kyphosis as well as occurrence of secondary surgery.

RESULTS

Of 580 graduates, 170 (29%) had minimum 5-year follow-up (37% male). Scoliosis etiology was congenital in 41 (24%), idiopathic 36 (21%), neuromuscular 51 (30%), and syndromic 42 (25%). Index surgery consisted of spine-based growing rods in 122 (71%) and rib-based distraction in 48 (29%). Mean age at index surgery was 6.8 years, and patients underwent an average of 5.4 lengthenings over an average of 4.9 years (range, 6 mo to 11 y). Last planned treatment was at an average age of 11.8 years (range, 7 to 17 years). Last planned treatment consisted of spinal fusion in 114 patients, 47 had growing implants maintained, 9 had implants removed. Average follow-up was 7.3 years (range, 5 to 13 y).When compared from postdefinitive treatment to 2-year follow-up, there was noted progression of the coronal curve angle (46±19 to 51±21 degrees, P=0.046) and kyphosis (48±20 to 57±25 degrees, P=0.03). However, between 2 and 5 years, no further progression occurred in the coronal (51±21 to 53±21 degrees, P=0.26) or sagittal (57±25 to 54±28 degrees, P=0.93) planes. When stratified based on etiology, there was no significant coronal curve progression between 2- and 5-year follow-up. When comparing spinal fusion patients to those who had maintenance of their growing construct, there was also no significant curve progression.Thirty-seven (21%) underwent at least 1 (average, 1.7; range, 1 to 7) revision surgery following graduation, and 15 of 37 (41%) underwent 2 or more revision surgeries. Reason for revision was implant revision (either GF or spinal fusion) in 34 patients, and implant removal in 3. On an average, the first revision was 2.5 years after the definitive treatment plan (range, 0.02 to 7.4 y). In total, 15 of 37 (41%) revisions occurred over 2 years following the final decision for treatment plan, and 7 of 37 (19%) occurred 5 or more years after the definitive treatment.Patients who underwent spinal fusion as a definitive treatment strategy were more likely to undergo revision surgery (27%) than patients who had their GF implants maintained (11%) (P=0.04).

CONCLUSIONS

Five years following "graduation" from growing surgery for early onset scoliosis, there is progression of curve magnitude in both the coronal and sagittal planes up to 2 years, with no further progression at 5 years. A total of 21% of patients undergo at least 1 revision surgery, and average time to revision surgery is over 2 years from last planned surgery. Risk of revision surgery was higher in patients who underwent a spinal fusion as their definitive treatment strategy.

LEVEL EVIDENCE

Level III-retrospective comparative.

TYPE OF EVIDENCE

Therapeutic.

THE MINIMALLY INVASIVE BIPOLAR TECHNIQUE FOR THE TREATMENT OF SPINAL DEFORMITIES IN CHILDREN AND ADOLESCENTS

ABSTRACT Scoliosis is a three-dimensional deformity of the spine that occurs during growth. Surgery is indicated when the curve progresses despite conservative treatment. The traditional surgical treatment involves correction of the deformity using segmental spinal fixation to obtain solid bone fusion by decortication and bone grafting. Vertebral osteotomies or even vertebrectomies may be required for huge deformities. These techniques provide good results, but they are invasive, involving lengthy surgery, increased blood loss, and longer recovery times. Therefore, we developed another technique: The Minimally Invasive Bipolar Technique, based on gradual internal correction of the deformity secondary to viscoelastic relaxation of the trunk. This method is aimed at reducing surgical risks while providing satisfactory results and improving quality of life for the patients and their families. Additionally, this technique is cost effective for public health. T ype of the study: Update article.

Risk Factors for Reoperation Following Final Fusion After the Treatment of Early-Onset Scoliosis with Traditional Growing Rods

BACKGROUND

Although there is a high rate of reoperation after final fusion following the treatment of early-onset scoliosis with use of traditional growing rods, the risk factors for reoperation are unknown. The purpose of the present study was to identify risk factors associated with the need for reoperation after final fusion for the treatment of early-onset scoliosis.

METHODS

A multicenter database for patients with early-onset scoliosis was retrospectively analyzed. Patients managed with traditional growing rods and final fusion were identified (n = 248). The inclusion criteria were ≥1 lengthening procedure with traditional growing rods and ≥2 years of follow-up after final fusion or revision surgery within 2 years after final fusion (167 patients; 67%). Patients requiring reoperation following final fusion were compared with patients who did not require reoperation. The data that were analyzed included demographic characteristics, comorbidities, spinal deformity characteristics, radiographic measurements, perioperative details, and complications during all stages of treatment. A multivariate regression model was used to identify independent risk factors.

RESULTS

The mean duration of follow-up from the initial visit to the latest visit was 10.7 ± 4.1 years, and the mean duration of follow-up after final fusion was 4.9 ± 3.1 years. Thirty-two (19%) of the 167 patients required reoperation following final fusion. Curve progression requiring revision surgery during lengthening with traditional growing rods (adjusted odds ratio [aOR], 21.137 per event; p = 0.028), the number of levels spanned with traditional growing rods (aOR, 1.378 per level; p = 0.007), and the duration of treatment with traditional growing rods (aOR, 1.220 per year; p = 0.035) were independently associated with revision surgery after final fusion.

CONCLUSIONS

Independent risk factors for curve progression requiring reoperation during lengthening with traditional growing rods that require operative intervention include increasing number of levels spanned with traditional growing rods and longer duration of treatment with traditional growing rods. These findings may help with patient counseling and potentially guide surgeon decision-making.

LEVEL OF EVIDENCE

Prognostic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Growth-preserving instrumentation in early-onset scoliosis patients with multi-level congenital anomalies

STUDY DESIGN

Retrospective.

OBJECTIVES

To assess final outcomes in patients with early-onset scoliosis (EOS) who underwent growth-preserving instrumentation (GPI). Various types of growth-preserving instrumentation (GPI) are frequently employed, but until recently had not been utilized long enough to assess final outcomes.

METHODS

GPI "graduates" with multi-level congenital curves were identified. Graduation was defined as a final fusion or 5 years of follow-up without planned future surgeries. Outcomes included radiographic parameters and complications.

RESULTS

26 patients were included. 11 had associated diagnoses; eight had fused ribs. 17 were treated with traditional growing rods, seven with vertically expandable prosthetic ribs, and two with Shilla procedures. The mean GPI spanned 12.3 levels including 10.7 motion segments, age at index surgery was 5.5 years, treatment spanned 7.5 years, and follow-up was 9.2 years. 24 patients underwent final fusion. Mean major curve decreased from 73° to 49° with index surgery (p < 0.01) and remained unchanged through a final follow-up. Final major curve was < 40° in 9 patients (35%), 40°-60° in 11 patients (42%), and > 60° in 6 patients (23%). None worsened throughout treatment. Mean T1-T12 height increased 2.4 cm with index surgery (p = 0.02) and 5.4 cm total (p < 0.01). T1-T12 height increased in all patients and was ultimately < 18 cm in 10 patients (38%), 18-22 cm in 10 patients (38%), and > 22 cm in 6 patients (23%). On average, there were 2.6 complications per patient, including 1.7 implant failures. 12 patients (46%) experienced ≥ 3 complications; four patients (15%) experienced none.

CONCLUSION

We observed successful prevention of deformity progression but substantial residual deformity among GPI graduates with multi-level congenital EOS. Most coronal curve correction was attained during GPI implantation; thoracic height improved throughout treatment. While some favorable results were found, treatment strategies allowing improved deformity correction would be valuable for this challenging population.

LEVEL OF EVIDENCE

Therapeutic-III.

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

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=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=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.

Outcomes of growing rods in a series of early-onset scoliosis patients with neurofibromatosis type 1

OBJECTIVE

Early-onset scoliosis (EOS) is not uncommon in patients with neurofibromatosis type 1 (NF1). Despite conservative treatment, spinal deformities progress and require early surgical intervention. To avoid potential interference with chest and trunk growth, growing rods (GRs) have been used effectively in EOS of various etiologies. In this study the authors sought to analyze the outcomes of GRs in EOS patients with NF1.

METHODS

This was a retrospective single-center cohort study that included consecutive EOS patients with NF1 who were treated with GRs and were followed up for a minimum of 2 years. Clinical and radiological analyses were performed preoperatively and until the last follow-up.

RESULTS

From to 2008 to 2017, 18 patients (6 male, 12 female) underwent GR surgery (14 single GRs, 4 dual GRs) at a mean age of 8 ± 2.1 years. Mean follow-up was 5 ± 2.4 years. Fifty-five lengthenings were performed at a mean rate of 3 lengthenings per patient (range 0-7). Ten of 14 single GRs (71%) were converted into dual GRs during treatment. No patient underwent definitive posterior spinal fusion (PSF) at GR treatment completion. The mean initial and last follow-up major curves were 57° and 36°, respectively (p < 0.001, 37% correction). The average T1-S1 increase was 13 mm/yr. Six of 9 hyperkyphotic patients had normal kyphosis at last follow-up. There were 26 complications involving 13 patients (72%), with 1 patient who required unplanned revision. The primary complications were instrumentation related, consisting of 17 proximal hook dislodgments, 6 distal pedicle screw pullouts, and 2 rod fractures. Only 1 patient experienced a mechanical complication after dual GR implantation. There were no wound infections.

CONCLUSIONS

The GR technique provided satisfactory spinal deformity control in EOS patients with NF1 while allowing substantial spinal growth. Adequately contoured dual GRs with proximal hooks placed in nondystrophic regions should be used to minimize implant-related complications. Surgeons should not attempt to correct kyphosis at GR implantation.

Is prophylactic formal fusion with implant revision necessary in non-ambulatory children with spinal muscular atrophy and growing rods who are no longer lengthened?

STUDY DESIGN

Single center, retrospective chart review.

OBJECTIVES

To determine if routine posterior spinal fusion (PSF) is unnecessary in non-ambulatory growing rod graduates with SMA. Most non-ambulatory children with SMA develop early-onset scoliosis (EOS). Posterior growing rods (GR) have been shown safe and effective in managing spinal deformities in these children. The best management of these children, once graduated from their GR, is currently unknown. In this study, we report the clinical results of managing these children without routine definitive fusion following a course of GR treatment.

METHODS

A single-center, retrospective chart and radiographic review was performed on children with SMA treated with posterior distraction GR, with a two-year minimum follow-up since final lengthening. Electronic medical records and radiographs were reviewed for demographic variables, Cobb measurements, implant revisions, occult radiographic implant failure, symptomatic failure, and/or conversion to PSF.

RESULT

12 patients (2 type 1, 9 type 2, 1 type 1/2) met inclusion criteria. Mean age at growing rod insertion was 6.2 years of age (range 4.1-8.2) and age at final lengthening 10.3 years of age (range 9.3-11.9). The mean time between last lengthening and latest clinical or radiographic review was 5.5 (range 2.1-9.0) years. Average mean pre, post, final Cobb angles were 71°, 27° (p < 0.001), 25°. Following final lengthening, only one patient required hardware revision and conversion to definitive fusion in attempts to alleviate chronic hip pain, which was unsuccessful. One additional patient was found to have an occult rod failure that has not required treatment.

CONCLUSION

While limited by sample size, this single-center cohort of non-ambulatory SMA patients with EOS treated with similar constructs suggests that routine, definitive fusion in SMA GR graduates may be unnecessary.

LEVEL OF EVIDENCE

Level IV.

Mean 6-Year Follow-up of Magnetically Controlled Growing Rod Patients With Early Onset Scoliosis: A Glimpse of What Happens to Graduates

BACKGROUND

There is no agreement on frequency of distractions of magnetically controlled growing rods (MCGRs) but more frequent and smaller amounts of distractions mimic physiological spine growth. The mid- to long-term follow-up and management at skeletal maturity is unknown.

OBJECTIVE

To analyze patients with mean 6 yr of follow-up and describe the fate of MCGR graduates.

METHODS

Early onset scoliosis (EOS) patients treated with MCGRs with minimum 4 yr of follow-up and/or at graduation were studied. Parameters under study included Cobb angle, spine and instrumented lengths, and rod distraction gains. Relationship between timing of rod exchanges with changes in rate of lengthening was studied.

RESULTS

Ten EOS patients with mean 6.1 yr of follow-up were studied. The greatest Cobb angle correction occurred at the initial implantation surgery and was stable thereafter. Consistent gains in T1-12, T1-S1, and instrumented segment were observed. Rate of lengthening reduced after the first year of use but improved back to initial rates after rod exchange. Seven of the ten patients experienced complications with reoperation rate of 40% for rod distraction failure and proximal foundation problems. Only mild further improvements in all radiological parameters were observed pre- and postfinal surgery. No clinically significant curve progression was observed for rod removal only. All postfinal surgery parameters remained similar at postoperative 2 yr.

CONCLUSION

This study provides an outlook of the end of MCGR treatment. Although this is a fusionless procedure, instrumented segments do experience stiffness limiting further correction and length gain during final surgery whether fusion or rod removal is performed.

Prospectively collected surgeon indications for discontinuation of a lengthening program for early-onset scoliosis

INTRODUCTION

At some point after children with early-onset scoliosis (EOS) undergo implantation of a distraction construct to control deformity and promote growth, a decision is made to discontinue lengthening. The purpose of this study was to evaluate surgeon indications for discontinuation of a lengthening program and to evaluate patient outcomes.

METHODS

As a part of a multicenter database, surgeons prospectively completed a questionnaire at the completion of growth-friendly treatment. Surgeon indications for discontinuation included patient age, pain/functional status, implant status, and spinal deformity parameters. Patient demographics, scoliosis type, deformity parameters, and length of time in a growing program were queried. Patients were treated with a final fusion or observation, and rate of secondary surgeries was analyzed.

RESULTS

Questionnaires were completed on 121 patients (61% female). EOS etiology was 31% neuromuscular, 43% congenital, 16% idiopathic, and 10% syndromic. Average age at initiation of growing program was 6.8 ± 3.1 years, and average age at discontinuation was 12.7 ± 2.5 years. The most commonly cited indications for discontinuation of a lengthening program included bone age/skeletal maturity (n = 46), patient age (n = 33), and diminishing returns with expansions (n = 33). A larger coronal Cobb angle was found in patients who underwent definitive fusion (65°) when compared with continued observation (55°, p = 0.001). Twenty-nine (24%) patients were initially treated with observation after completion of a growing construct. In this subgroup, at a minimum of 2 years' (average 3.8 years') follow-up, 26/29 (90%) patients remained stable with observation alone; whereas, three (10%) underwent delayed final fusion surgery.

CONCLUSIONS

The most common surgeon-cited indications for discontinuation of a lengthening program in EOS patients are skeletal maturity and patient age. The majority of patients (76%) underwent definitive spinal fusion after discontinuation of a lengthening program; whereas, those treated with observation alone had a survivorship of 90% at a minimum follow-up of two years.

Radiographic Outcome and Complication Rate of 34 Graduates After Treatment With Vertical Expandable Prosthetic Titanium Rib (VEPTR): A Single Center Report

BACKGROUND

The final strategy for graduates from growth-sparing surgery is challenging. The purpose of this study was to evaluate the radiographic outcome and complications of patients with early onset scoliosis (EOS) who have graduated from vertical expandable prosthetic titanium rib (VEPTR) treatment, either undergoing final fusion surgery or following a nonfusion approach.

METHODS

Final treatment for VEPTR graduates was divided in "VEPTR in situ without final fusion," "removal of VEPTR without final fusion," and "removal of VEPTR with instrumented final fusion." Radiographic evaluations included main coronal Cobb angle and main kyphosis pre and post VEPTR implantation, at the end of implant lengthening, after final fusion (if applicable), and at latest follow-up. Complications during VEPTR treatment and in case of final fusion were reported.

RESULTS

In total, 34 VEPTR graduates were included; 17 underwent final fusion surgery, and 17 followed a nonfusion strategy. Average coronal Cobb angle before VEPTR implantation was 70±23 degrees (range, 21 to 121 degrees), and 65±22 degrees (range, 17 to 119 degrees) at latest follow-up. Average main kyphosis angle was 53±27 degrees (range, 6 to 137 degrees) before VEPTR, and 69±34 degrees (range, 10 to 150 degrees) at latest follow-up. There was a 41% complication rate with final fusion surgery.

CONCLUSIONS

There is a high complication rate during VEPTR treatment and with final fusion surgery. The stiffness of the spine and thorax allow for only limited correction when performing a final instrumented spondylodesis. Avoiding final fusion may be a viable alternative in case of good coronal and sagittal alignment.

LEVEL OF EVIDENCE

Level IV-therapeutic.

Standard and magnetically controlled growing rods for the treatment of early onset scoliosis

Distraction based spinal instrumentation represents the most common and standard surgical technique to correct early onset scoliosis (EOS), i.e., scoliosis which has been diagnosed before the age of 10 years. Surgical treatment of EOS aims at controlling spinal deformity while maintaining spinal growth which is mandatory for the development of normal lung capacity. To achieve these goals the spinal instrumentation needs to be distracted to facilitate spinal growth during treatment. Distraction can be obtained by repeated surgical lengthenings (traditional growing rods, TGRs) or using magnetically controlled growing rods (MCGRs), which can be lengthened using external remote controller on an outpatient basis. The outcomes of TGR instrumentation for EOS are well described with follow-up until skeletal maturity: normal spinal growth can be maintained, 40-50% of the scoliosis can be corrected, but there is an over 50% risk of complications including deep wound infection, rod failure, and instrumentation pull-out. MCGR instrumentation may reduce the risk of wound related complications, provides similar deformity correction, but may not provide as much spinal growth. Metallosis around the instrumentation necessitates MCGR removal and definitive final instrumented fusion at the end of growth friendly management. Even severe EOS can be treated using distraction based spinal instrumentation.

Long term outcome of vertical expandable prosthetic titanium rib treatment in children with early onset scoliosis

The vertical expandable prosthetic titanium rib (VEPTR) device was originally developed for the treatment of thoracic insufficiency syndrome with the aim of improving respiratory function of affected patients. Although clinically obvious, the changes in pulmonary function of VEPTR-treated patients are difficult to assess when using common lung function tests, and newer techniques based on functional magnetic resonance imaging (MRI) are currently being evaluated. The potential of improving lung function and simultaneously controlling the spinal deformity has continuously broadened the spectrum of indications for VEPTR, not least due to the frequent reports of complications with spine-based traditional growing rods (tGR). However, the initial enthusiasm of spine-sparing deformity correction has progressively subsided with the increasing number of reports on complications, including the detection of extraspinal ossifications along the implants and across ribs. The avoidance of repetitive surgical implant lengthening with the availability of motorized distraction-based implants has further diminished the use of VEPTR, especially in the absence of volume-depletion deformities of the thorax. In view of the still scarce reporting on the ultimate strategy of VEPTR treatment and the lack of long-term follow-up of patients receiving growth-sparing surgery, only limited conclusions can be drawn so far. Based on the available reports, however, the intended deformity corrections with final fusion surgeries can be achieved to a rather limited extent, while the complication and reoperation rates are still very high.

Outcomes at Skeletal Maturity of 34 Children With Scoliosis Treated With a Traditional Single Growing Rod

STUDY DESIGN

Retrospective case series.

OBJECTIVES

To analyze the outcomes at skeletal maturity of patients treated with a single traditional growing rod (GR). To compare results of patients according to whether posterior spinal fusion (PSF) was performed at treatment completion.

SUMMARY OF BACKGROUND DATA

Few studies examined the end results of GRs at skeletal maturity. There is no agreement on requirement of PSF at GR treatment completion.

METHODS

Clinical and radiological analysis of consecutive patients with severe and/or progressive scoliosis treated initially with traditional single GR. Group comparisons of patients with PSF and without fusion surgery at treatment completion.

RESULTS

Thirty-four patients underwent traditional single GR implantation at a median age of 11.7 years. Median follow-up was 6.5 years. At last follow-up, T1-S1 distance was increased by a median 116 mm (P < 0.001) and median major curve Cobb angle was changed from 55° preoperatively to 30° (P < 0.001). Complications included 26 rod fractures, 1 implant prominence, 4 proximal junctional kyphosis, 2 proximal hook dislodgments, and 2 wound infections. At the beginning our experience, PSF was performed systematically in 17 patients. Relying on spinal ankylosis, 17 patients were subsequently not fused at GR treatment completion (single GR removed N = 2, single GR retained N = 7, dual GR surgery N = 8). There were no statistical differences between groups in improvements of radiological parameters from preoperative GR insertion to last follow-up. No GR fracture occurred after dual GR surgery.

CONCLUSION

Single GR allows curve control and promotes spinal growth. Dual GR is, however, recommended for rod fracture prevention and better correction maintenance. In patients with satisfactory deformity correction at skeletal maturity, one may consider retaining dual GR instead of performing PSF.

LEVEL OF EVIDENCE

4.

Correction of adult spinal deformity with a minimally invasive fusionless bipolar construct: Preliminary results

INTRODUCTION

Fusion in adult spinal deformity has a high rate of complications. Fusionless constructs in children and percutaneous fixation in adults are now being used routinely. The aim of this study was to evaluate the preliminary results of a minimally invasive fusionless surgical technique used to correct adult spinal deformity.

MATERIALS AND METHODS

Thirty-eight patients with an average age of 45 years (15-76) with major spinal deformity requiring extensive arthrodesis from the upper thoracic region to the pelvis were operated consecutively and followed prospectively. Two hooks were implanted at the top and two iliosacral screws at the bottom. Two large rods connected by dominos to two small rods joined the upper hooks to the lower screws. The surgical data (operative time and bleeding), the radiological findings (Cobb angle, sagittal parameters, C7-plumbline AP and lateral), the complication rate and the morbidity were evaluated at the last follow-up visit.

RESULTS

The primary curvature was reduced by 40% from a mean of 58.5° (26-146) to 35.2° (3-109) (p<0.001). A clear decrease in operating time (270min) and blood loss (50cc/level) were observed. The length of hospitalization averaged 18 days (6-66), including an 8-15 day long preoperative traction period for 11 patients. We found 7 infectious complications, 11 early mechanical complications and one case of paraplegia due to severe kyphoscoliosis.

CONCLUSION

The corrections obtained are comparable to those reported in the literature for standard constructs. Most patients had an uneventful postoperative course. The early complications observed led us to very carefully select the indications. Long-term follow-up is essential.

Outcomes of Primary and Conversion Magnetically Controlled Growth Rods Are Different at Two-Year Follow-up: Results of North American Release

STUDY DESIGN

Multicenter retrospective review.

OBJECTIVES

To compare the radiographic outcomes and complication rates in patients with primary and conversion magnetically controlled growing rod (MCGR) implants at one and two years after surgery.

SUMMARY OF BACKGROUND DATA

Many initial early-onset scoliosis (MCGR) implantations in the United States were conversions from other types of growth-friendly systems, and the outcome similarities and differences between primary and conversion MCGR implantation procedures are still relatively unknown.

METHODS

Multicenter retrospective review of EOS patients from two multicenter EOS registries identified consecutive EOS patients treated from 2014 to 2017 with a minimum of one-year follow-up. In addition, a subset of these patients who had two-year follow-up were further analyzed.

RESULTS

In total, 383 MCGR patients were identified, of which 272 (71%) were primary (P) and 111 (29%) were conversion (C). Group P patients had significantly greater coronal curves at the time of MCGR implantation and greater initial coronal correction. There was no statistically significant difference in Cobb correction at one year or between follow-up at one and two years. The preimplantation thoracic spine height was identical in both groups, with statistically greater improvement at initial implantation in P than in C patients. Significantly greater height gains were seen in P than in C patients in the one-year follow-up cohort. There was a higher rate of complications in the C group than in the P group; however, the difference was not statistically significant. Overall, most complications were implant-related. No loss of curve correction occurred in either group.

CONCLUSIONS

Patients with primary MCGR insertion can be expected to have greater radiographic correction and spine length gain than those with conversion from growth-friendly instrumentation to MCGR, most likely because of increased spine stiffness in conversion patients. The rate of complications, primarily implant-related, remains higher in conversion than in primary insertion patients.

LEVEL OF EVIDENCE

Level III.

In Patients with Early-Onset Scoliosis, Can Growing Rods Be Removed Without Further Instrumentation? An Evidenced-Based Review

Early-onset scoliosis (EOS) is defined by the presence of spinal deformity in children 10 years of age or younger. Left untreated, patients with EOS are at high risk for thoracic insufficiency and early demise. This article provides a critical review of a recent prospective cohort study of children with EOS: "Graduation Protocol After Growing-Rod Treatment: Removal of Implants without New Instrumentation Is Not a Realistic Approach," by Kocyigit and colleagues (J Bone Joint Surg Am. 2017;99(18):1554-1564). Treatment for EOS requires deformity correction while accommodating the growing spine. Dual growing rod implantation is a well-described technique that consists of the placement of two telescoping rods anchored to vertebrae proximal and distal to the apex of the curve. Multiple lengthening procedures are then performed as the child grows. Management of the endpoint of growing rod treatment remains controversial, with high complication rates associated with final fusion. As an alternative to final fusion or implant retention, Kocyigit and colleagues examined the removal of growing rods without spinal fusion and found that this procedure resulted in substantial worsening of the deformity in nine out of ten patients. This treatment group was terminated on ethical grounds. We believe this important result demonstrates that the removal of implants without fusion is an unacceptable treatment strategy that leads to poor outcomes.

Hybrid Growing Rod Technique of Osteotomy With Short Fusion and Spinal Distraction: An Alternative Solution for Long-Spanned Congenital Scoliosis

STUDY DESIGN

Retrospective study.

OBJECTIVE

The current study aimed to evaluate the effectiveness of the hybrid growing rod (GR) technique for the treatment of young children with congenital scoliosis (CS).

SUMMARY OF BACKGROUND DATA

Congenital vertebral anomalies within long-spanned kyphoscoliosis were difficult to be managed by either definitive spinal fusion or standard GR technique. Hybrid technique of one-stage posterior osteotomy with short fusion and GR distraction was proposed in previous studies. There is, however, paucity of data regarding its effectiveness.

METHODS

Thirteen patients (mean age, 5.4 ± 2.0 yr) who had undergone hybrid GR treatment were retrospectively reviewed, including 8 patients treated with single GR and 5 patients with dual GR. All of their radiographic data were measured, and surgical complications were recorded.

RESULTS

On average, the current cohort had 4.1 ± 1.7 lengthening procedures. After the index surgery, the major curve improved remarkably from 86.4° ± 11.9° to 37.3° ± 12.4° (P < 0.001). The global kyphosis significantly decreased from 66.8° ± 16.1° to 33.3° ± 3.5° postoperatively. Both value remained steady during follow-up. There were no significant difference between single GR and dual GR groups in terms of the coronal deformity correction, whereas correction loss of global kyphosis in single GR group was significantly higher than that in dual GR group (P = 0.039). After the index surgery, T1-S1 height averagely gained 4.4 ± 0.8 cm and it grew at an average rate of 1.31 ± 0.24 cm/yr during the follow-up. Two complications were identified in two patients, including one with rod fracture and one with proximal junctional kyphosis.

CONCLUSION

The hybrid GR technique was effective in correcting spinal deformity and allowing continuous spinal growth. The optimal indications were young children with apical vertebrae anomalies and a long-spanned kyphoscoliosis.

LEVEL OF EVIDENCE

3.

Surgical and Health-related Quality-of-Life Outcomes of Growing Rod "Graduates" With Severe versus Moderate Early-onset Scoliosis

STUDY DESIGN

A retrospective review of a prospective, multicenter database.

OBJECTIVE

The aim of this study was to compare surgical and quality-of-life outcomes at the end of growing rod treatment in patients with severe versus moderate early-onset scoliosis (EOS).

SUMMARY OF BACKGROUND DATA

Knowledge of the outcomes of severe EOS after growth-friendly treatment is limited because this condition is uncommon.

METHODS

We identified 40 children with severe EOS (major curve ≥90°) treated with growing rods before age 10 with minimum 2-year follow-up after last lengthening or final fusion. From the same registry, we matched 40 patients with moderate EOS (major curve < 90°). Twenty-seven patients in the severe group and 12 in the moderate group underwent final fusion (P < 0.001).

RESULTS

Mean preoperative curves were 102° (range, 90°-139°) in the severe group and 63° (range, 33°-88°) in the moderate group (P < 0.001). At final follow-up, mean curves were 56° (range, 10°-91°) and 36° (range, 12°-89°), respectively (P < 0.001). Fourteen (35%) children in the severe group and 32 (80%) in the moderate group had scoliosis of < 45° at final follow-up [risk ratio (RR), 0.44; 95% confidence interval (95% CI), 0.20-0.57]. At final follow-up, 30 (75%) children in the severe group and 35 (88%) in the moderate group had achieved T1-T12 length of ≥18 cm (RR, 0.86; 95% CI, 0.70-1.09). Thirty-five children in the severe group and 26 in the moderate group had at least one complication (RR, 1.35; 95% CI, 1.05-1.73). Mean 24-Item Early-Onset Scoliosis Questionnaire scores were similar between groups at final follow-up.

CONCLUSION

Delaying surgery until the major curve has progressed beyond 90° is associated with larger residual deformity and more complications than treating at a lesser curve magnitude. Quality-of-life outcomes were similar between those with severe and moderate EOS.

LEVEL OF EVIDENCE

3.

Decision Making of Graduation in Patients With Early-Onset Scoliosis at the End of Distraction-Based Programs: Risks and Benefits of Definitive Fusion

STUDY DESIGN

Retrospective comparative analysis.

OBJECTIVE

Study early-onset scoliosis (EOS) graduated patients to establish founded criteria for graduation decision making and determine the risks and benefits of definitive fusion.

SUMMARY OF BACKGROUND DATA

EOS is treated by growth-friendly techniques until skeletal maturity. Afterwards, patients can be "graduated," either by definitive fusion (posterior spinal fusion [PSF]) or by retaining the previous implants (Observation) with no additional surgery. Criteria for this decision making and the outcomes of definitive fusion are still underexplored.

METHODS

We analyzed a consecutive cohort of "graduated" patients after a distraction-based lengthening program. We gathered demographic, radiographic, and surgical data. The results of the two final treatment options were compared after 2 years' follow-up.

RESULTS

A total of 32 patients were included. Four patients had incomplete records. Thirteen underwent PSF, and 15 were observed. The mean age at initial treatment was 8 ± 3 years, with a mean follow-up of 8.3 ± 2.9 years. Both groups had similar preoperative and final radiographic parameters (p > .05). The criteria for undergoing PSF were as follows: implant-related complications, main curve magnitude (PSF = 63.2° ± 9° vs. OBS = 47.9° ± 15°; p = .008), curve progression >10°, and sagittal misalignment (SVA). During PSF 12/13 patients underwent multiple osteotomies, one vertebrectomy, and 3 costoplasties. Surgical time was 291.5 ± 58 minutes; blood loss was 946 ± 375 mL; and the number of levels fused was 13.7. Coronal deformity was corrected 31%, T1-S1 length gained was 31 ± 19.6 mm and T1-T12 length gained was 9.3 ± 39 mm; kyphosis was reduced by 22%. However, coronal balance worsened by 2.3 ± 30.8 mm. No major complications were encountered in these patients.

CONCLUSIONS

Graduation by PSF depended on unacceptable or progressive major curve deformity, sagittal misalignment, or complications with previous implants. Observation depended on curve stabilization, Cobb <50°, and coronal misalignment <20 mm. Definitive fusion effectively corrected coronal and sagittal deformity and increased trunk height. However, it exposed patients to a very demanding surgery without improvement in coronal balance.

LEVEL OF EVIDENCE

Level III, therapeutic.

Experience with definitive instrumented final fusion after posterior-based distraction lengthening in patients with early-onset spinal deformity: single center results

Limited reports exist with regard to clinical and radiographic details of patients with early-onset spinal deformity (EOSD) undergoing definitive instrumented final fusion (FF) following implantation of a growing construct. Charts and radiographs were queried for all patients who underwent FF after management of EOSD with a distraction-based posterior construct at a single institution from 2006 to 2017. Patients managed during the growth modulation period with either proximal rib or spinal fixation were included. Thirteen patients qualified for inclusion. Spinal deformity etiologies were varied (neuromuscular: 5, idiopathic: 4, congenital: 4). Average age at implantation was 6.5 years, and patients underwent an average of 8.15 lengthening procedures over an average of 69 months. After the growing program, modest correction in main coronal Cobb was obtained at FF (average 52.4° before FF, 37.6° following FF, P<0.001; average percent improvement of 27%). Five patients required posterior column osteotomies. Using criteria proposed by Flynn and colleagues, 'minimal' coronal correction was achieved in 23% of patients and 'moderate' in 77%. No patient achieved 'substantial' (>50%) correction. Subjective poor bone quality was appreciated in 67% of patients, and 85% were noted to have areas of autofusion over previously spanned levels. Two (15%) patients sustained a total of four complications. After growth modulation procedures, EOSD deformities are generally stiff, bone quality is often subjectively poor, and autofusion is common, even after use of proximally rib-based systems. Modestly improved coronal Cobb correction can be obtained at FF but may require single or multiple posterior osteotomies. Intraoperative difficulties can be expected, and clinicians should be alert for intraoperative and postoperative complications.

Minimizing Spine Autofusion With the Use of Semiconstrained Growing Rods for Early Onset Scoliosis in Children

BACKGROUND

A new growing rod (GR) design, the semiconstrained growing rod (SCGR), with the added advantage of axial rotation freedom within the components, has been introduced at our center which has been shown to be growth friendly. We hypothesize that the SCGR system would reduce autofusion in vivo, thereby maximizing the coronal plane correction, T1-S1 growth, and the final correction achieved at definitive fusion for children with an early onset scoliosis.

METHODS

In total, 28 patients had either single or dual 5.5 mm diameter SCGR placed minimally invasively through a submuscular approach. Surgical lengthening procedures occurred approximately every 6 months until the definitive fusion procedure was performed for 18 patients. Scoliosis, kyphosis, and lordosis angles, T1-S1 trunk length, and any complications encountered were evaluated.

RESULTS

For the full cohort, before GR insertion, the mean major Cobb curve angle was 72.4 degrees (SD, 18.8; range, 45 to 120), mean T1-S1 trunk length was 282 mm (SD, 59; range, 129 to 365), and at the latest follow-up (mean 6.9 y, SD 3.3, range 2.0 to 13.0), 38.8 degrees (SD, 17.5; range 10 to 90) and 377 mm (SD, 62; range, 225 to 487), respectively. For the subset of 18 patients who have had their final instrumented fusion surgery, the definitive surgery procedure alone produced a correction of the major Cobb curve angle by mean 20.3 degrees (SD, 16.1; P<0.0001), and an increase in the T1-S1 trunk length of mean 31.7 mm (SD, 23.1; P<0.0001). There were 14 complications involving 11 of the 28 patients, giving rise to 5 unplanned surgical interventions and 1 case where GR treatment was abandoned.

CONCLUSIONS

SCGR patients exhibited statistically significant increase in T1-S1 trunk length and statistically significant decrease in the severity of scoliosis over the course of GR treatment and again, importantly, with the definitive fusion surgery, suggesting that autofusion had been minimized during GR treatment with relatively low complication rates.

LEVEL OF EVIDENCE

Level IV-case series.

A re-evaluation of the effects of dual growing rods on apical vertebral rotation in patients with early-onset scoliosis and a minimum of two lengthening procedures: a CT-based study

OBJECTIVE This study aimed to evaluate the correction results of traditional dual growing rods (DGRs) on axial rotation using CT scans and to further explore the relationships between axial and torso deformities in patients with early-onset scoliosis (EOS). METHODS Patients with EOS who were treated with traditional DGRs between January 2006 and December 2014 were retrospectively reviewed. Plain radiographs were used to assess the degree of coronal and sagittal deformity. The apical vertebral rotation (AVR) and rib hump (RH) were measured on CT scans at the apical vertebra. Pearson or Spearman rank correlation analyses were used to analyze the associations between spinal and torso deformities. RESULTS A total of 27 patients (10 boys and 17 girls, average age 6.5 ± 1.7 years) were enrolled in this study. The average number of lengthenings per patient was 5.0 ± 1.9, with a mean follow-up duration of 52.9 ± 18.2 months. The apical vertebral translation, apical vertebral body-rib ratio (AVB-R), AVR, and RH parameters were significantly decreased after the initial surgery (p < 0.05) but showed notable progression at the latest follow-up evaluation (p < 0.05). The preoperative AVR and its correction after index surgery were significantly correlated with the preoperative values as well as with the corrections of the major Cobb angle, AVB-R, and RH. During the follow-up period, significant correlations were found between the deterioration of AVR and the AVB-R and also between the deterioration of AVR and the RH from the initial surgery to the latest follow-up. CONCLUSIONS Significant AVR correction can be achieved by DGR techniques after the initial surgery. However, this technique weakly prevents the deterioration of AVR during the follow-up period.