VEPTR: past experience and the future of VEPTR principles

A multicenter evaluation of the time and travel burden on families with children treated for early-onset scoliosis

PURPOSE

Patients who undergo growth-friendly (GF) treatment for early-onset scoliosis (EOS) undergo multiple clinical and surgical encounters. We sought to quantify the associated temporal and travel burden and estimate subsequent cost.

METHODS

Four centers in an international study group combined data on EOS patients who underwent surgical GF treatment from 2006 to 2021. Data collected included demographics, scoliosis etiology, GF implant, encounter type, and driving distance. We applied 2022 IRS and BLS data or $0.625/mile and $208.2/day off work to calculate a relative financial burden.

RESULTS

A total of 300 patients were analyzed (55% female). Etiologies were: congenital (33.3%), idiopathic (18.7%), neuromuscular (30.7%), and syndromic (17.3%). The average age at the index procedure was 5.5 years. For the 300 patients, 5899 encounters were recorded (average 18 encounters/patient). Aggregate encounter types were 2521 clinical office encounters (43%), 2045 surgical lengthening encounters (35%), 1157 magnetic lengthening encounters (20%), 149 spinal fusions (3%), and 27 spinal fusion revisions (0.5%). When comparing patients by scoliosis etiology or by GF implant type, no significant differences were noted in the total number of encounters or average travel distance. Patients traveled a median round trip distance of 158 miles/encounter between their homes and treating institutions (range 2.4-5654 miles), with a cumulative median distance of 2651 miles for the entirety of their treatment (range 29-90,552 miles), at an estimated median cost of $1656.63. The mean number of days off work was 18 (range 3-75), with an associated loss of $3643.50 in income.

CONCLUSION

Patients with EOS averaged 18 encounters for GF surgical treatment. These patients and their families traveled a median distance of 158 miles/encounter, with an estimated combined mileage and loss of income of $5300.

Scoliosis Caused by Rib Fusion after Thoracotomy for Esophageal Atresia: A Case Report and Surgical Approach

Introduction

This case report abstract discusses scoliosis, a multifactorial three-dimensional spinal deformity, including lateral curvatures on the frontal plane characterized by Cobb angle measurement, vertebral rotation on the axial plane and sagittal deformity. Scoliosis can be mild, moderate, or severe, and if left untreated, it can lead to further deformity and compromise cardiopulmonary function. Scoliosis is classified into early onset and late onset, with idiopathic scoliosis being the most common form. Early-onset scoliosis has various etiologies, including idiopathic, congenital, neuromuscular, and syndromic. Early management is crucial to minimize complications, such as restrictive ventilatory disorder and pulmonary dysplasia. This case report focuses on an iatrogenic cause of scoliosis due to rib synostosis, which is not included in the classification. Treatment options include non-operative management and surgical interventions, with the use of vertical expandable prosthetic titanium rib (VEPTR) thoracoplasty to correct the spinal deformity.

Case Report

This article illustrates the case of a 13-year-old girl who developed a left thoracic scoliosis caused by ribs fusion, following multiple right thoracotomies during childhood for esophageal atresia with tracheoesophageal fistula. No vertebral abnormalities were reported. Considering the young age of the girl, spinal fusion was not considered. A VEPTR associated with an excision of the fused ribs was used to treat this patient.

Conclusion

The aim of this article was to illustrate the importance of a regular follow-up for the patients who have undergone multiples thoracotomies during their childhood even without vertebral abnormalities and propose an early approach to avoid spinal fusion in early adulthood.

Effects of spinal deformities on lung development in children: a review

Scoliosis before the age of 5 years is referred to as early-onset scoliosis (EOS). While causes may vary, EOS can potentially affect respiratory function and lung development as children grow. Moreover, scoliosis can lead to thoracic insufficiency syndrome when aggravated or left untreated. Therefore, spinal thoracic deformities often require intervention in early childhood, and solving these problems requires new methods that include the means for both deformity correction and growth maintenance. Therapeutic strategies for preserving the growing spine and thorax include growth rods, vertically expandable titanium artificial ribs, MAGEC rods, braces and casts. The goals of any growth-promoting surgical strategy are to alter the natural history of cardiorespiratory development, limit the progression of underlying spondylarthrosis deformities and minimize negative changes in spondylothorax biomechanics due to the instrumental action of the implant. This review further elucidates EOS in terms of its aetiology, pathogenesis, pathology and treatment.

Molecular diagnosis and novel genes and phenotypes in a pediatric thoracic insufficiency cohort

Thoracic insufficiency syndromes are a genetically and phenotypically heterogeneous group of disorders characterized by congenital abnormalities or progressive deformation of the chest wall and/or vertebrae that result in restrictive lung disease and compromised respiratory capacity. We performed whole exome sequencing on a cohort of 42 children with thoracic insufficiency to elucidate the underlying molecular etiologies of syndromic and non-syndromic thoracic insufficiency and predict extra-skeletal manifestations and disease progression. Molecular diagnosis was established in 24/42 probands (57%), with 18/24 (75%) probands having definitive diagnoses as defined by laboratory and clinical criteria and 6/24 (25%) probands having strong candidate genes. Gene identified in cohort patients most commonly encoded components of the primary cilium, connective tissue, and extracellular matrix. A novel association between KIF7 and USP9X variants and thoracic insufficiency was identified. We report and expand the genetic and phenotypic spectrum of a cohort of children with thoracic insufficiency, reinforce the prevalence of extra-skeletal manifestations in thoracic insufficiency syndromes, and expand the phenotype of KIF7 and USP9X-related disease to include thoracic insufficiency.

Changes in research quality and surgical trends at the international congress on early-onset scoliosis

PURPOSE

The founding of the International Congress for Early Onset Scoliosis (ICEOS) and first annual meeting in 2007 represented a significant milestone in advancing the care of patients with EOS. Due to the complexity and rarity of EOS, this annual conference is the premiere venue for physicians, researchers, and advanced practice providers to identify and understand the best treatments for children with EOS. This study examines the trend of various treatment modalities presented at ICEOS and the changes in research quality since its inception.

METHODS

Podium presentations from the 2007 through 2021 ICEOS annual meetings were reviewed to determine the number of study patients, use of a study group, and key features of study design. Treatment strategies being evaluated were recorded and included non-operative treatments (casting/bracing), traditional growing rods (TGR), vertical expandable prosthetic titanium rib (VEPTR), Shilla growth guidance, magnetically controlled growing rods (MCGR), and vertebral body tethering (VBT). Linear regressions were performed to analyze changes in research topic and study group utilization.

RESULTS

A total of 532 abstracts were reviewed. An average of 97.5 ± 81.3 patients were included per study with a significant increase from 42.3 ± 89.7 in 2007 to 337.6 ± 587.4 in 2021 (r² = 0.632, p < 0.001). A total of 130 (24.4%) abstracts resulted from multicenter study groups with the proportion increasing significantly from 13.0% in 2007 to 36.4% in 2021 (p = 0.039, r² = 0.289). The majority (96.2%) of study group-based projects were from either the Growing Spine Study Group (GSSG), Chest Wall and Spine Deformity Study Group (CWSDG), Children's Spine Study Group (CSSG), or the Pediatric Spine Study Group (PSSG). Additionally, a significant increase in studies utilizing patient-reported outcome measures (PROMs) was observed (r² = 0.336, p = 0.023). Significant increases in the proportion of presentations discussing MCGR (r² = 0.738, p < 0.001) and VBT (r² = 0.294, p = 0.037) as surgical treatments were observed.

CONCLUSION

The trends in EOS device implantation observed in registry studies align with the trends in research presented at ICEOS including the increased proportion of studies focusing on MCGR and VBT over the past decade. An attempt to increase the quality of research presented at ICEOS through multicenter study groups, increased patient recruitment, and utilization of PROMs has been seen since its inception.

LEVEL OF EVIDENCE

V.

Assessment of Regional Functional Effects of Surgical Treatment in Thoracic Insufficiency Syndrome via Dynamic Magnetic Resonance Imaging

BACKGROUND

Quantitative regional assessment of thoracic function would enable clinicians to better understand the regional effects of therapy and the degree of deviation from normality in patients with thoracic insufficiency syndrome (TIS). The purpose of this study was to determine the regional functional effects of surgical treatment in TIS via quantitative dynamic magnetic resonance imaging (MRI) in comparison with healthy children.

METHODS

Volumetric parameters were derived via 129 dynamic MRI scans from 51 normal children (November 2017 to March 2019) and 39 patients with TIS (preoperatively and postoperatively, July 2009 to May 2018) for the left and right lungs, the left and right hemi-diaphragms, and the left and right hemi-chest walls during tidal breathing. Paired t testing was performed to compare the parameters from patients with TIS preoperatively and postoperatively. Mahalanobis distances between parameters of patients with TIS and age-matched normal children were assessed to evaluate the closeness of patient lung function to normality. Linear regression functions were utilized to estimate volume deviations of patients with TIS from normality, taking into account the growth of the subjects.

RESULTS

The mean Mahalanobis distances for the right hemi-diaphragm tidal volume (RDtv) were -1.32 ± 1.04 preoperatively and -0.05 ± 1.11 postoperatively (p = 0.001). Similarly, the mean Mahalanobis distances for the right lung tidal volume (RLtv) were -1.12 ± 1.04 preoperatively and -0.10 ± 1.26 postoperatively (p = 0.01). The mean Mahalanobis distances for the ratio of bilateral hemi-diaphragm tidal volume to bilateral lung tidal volume (BDtv/BLtv) were -1.68 ± 1.21 preoperatively and -0.04 ± 1.10 postoperatively (p = 0.003). Mahalanobis distances decreased after treatment, suggesting reduced deviations from normality. Regression results showed that all volumes and tidal volumes significantly increased after treatment (p < 0.001), and the tidal volume increases were significantly greater than those expected from normal growth for RDtv, RLtv, BDtv, and BLtv (p < 0.05).

CONCLUSIONS

Postoperative tidal volumes of bilateral lungs and bilateral hemi-diaphragms of patients with TIS came closer to those of normal children, indicating positive treatment effects from the surgical procedure. Quantitative dynamic MRI facilitates the assessment of regional effects of a surgical procedure to treat TIS.

LEVEL OF EVIDENCE

Diagnostic Level II. See Instructions for Authors for a complete description of levels of evidence.

Risk of ventriculoperitoneal shunt malfunction in operatively treated early onset spinal deformity

PURPOSE

Ventriculoperitoneal (VP) shunt placement is a common neurosurgical procedure performed in patients with early onset scoliosis (EOS). To provide insight into the risks of spine lengthening operations, we investigate the rate of VP shunt complications in patients with EOS undergoing spinal deformity correction interventions.

METHODS

A retrospective review was performed of all patients with EOS at a single institution undergoing spinal deformity correction procedures from 2007 to 2018. Patients having undergone VP shunt implantation prior to deformity correction were included. A minimum of 2-year follow-up was required for inclusion. Clinical records and imaging studies were reviewed.

RESULTS

Nineteen patients with VP shunts underwent Vertical Expandable Prosthetic Titanium Rib (VEPTR) implantation for treatment of early onset spinal deformity. The mean age at shunt placement and spine instrumentation surgery was 13.7 months (1 day to 13 years) and 6.1 years (0.5-15.1) respectively. The diagnoses associated with shunt implantation were: 12 spina bifida, 3 structural defects or obstructions, 2 intraventricular hemorrhage, 1 cerebral palsy, and 1 campomelic dwarfism. During the first 2 years following rib-based insertion, there was a mean of 2.5 expansion/revision procedures (0-5) with no shunt-related complications. The mean length of follow-up in this series was 7.0 years (2.6-13.2). A total of three (16%) patients required shunt revision following their rib-based device insertion, two patients with proximal shunt malfunctions and one with a mid-catheter breakage, at 2.4, 2.6, and 5.6 years, respectively, after rod implantation (Fig. 2). Each of these shunt revisions occurred more than 50 days following an expansion procedure (1.9, 2.9, and 5.7 months, respectively).

CONCLUSION

Growing instrumentation procedures in EOS are associated with low risk for post-operative shunt complications in patients with ventriculoperitoneal shunts. There were no shunt revision procedures performed in the first 2 years following rib-based device insertion. Sixteen percent of patients went on to require a shunt revision at some point during their follow-up, which is comparable to the baseline rate of shunt revision in non-EOS patients.

LEVEL OF EVIDENCE

IV, Case series.

Comparison of surgical interventions for the treatment of early-onset scoliosis: a systematic review and meta-analysis

OBJECTIVE

Several growth-preserving surgical techniques are employed in the management of early-onset scoliosis (EOS). The authors' objective was to compare the use of traditional growing rods (TGRs), magnetically controlled growing rods (MCGRs), Shilla growth guidance techniques, and vertically expanding prosthetic titanium ribs (VEPTRs) for the management of EOS.

METHODS

A systematic review of electronic databases, including Ovid MEDLINE and Cochrane, was performed. Outcomes of interest included correction of Cobb angle, T1-S1 distance, and complication rate, including alignment, hardware failure and infection, and planned and unplanned reoperation rates. The percent changes and 95% CIs were pooled across studies using random-effects meta-analysis.

RESULTS

A total of 67 studies were identified, which included 2021 patients. Of these, 1169 (57.8%) patients underwent operations with TGR, 178 (8.8%) Shilla growth guidance system, 448 (22.2%) MCGR, and 226 (11.1%) VEPTR system. The mean ± SD age of the cohort was 6.9 ± 1.2 years. The authors found that the Shilla technique provided the most significant improvement in coronal Cobb angle immediately after surgery (mean [95% CI] 64.3% [61.4%-67.2%]), whereas VEPTR (27.6% [22.7%-33.6%]) performed significantly worse. VEPTR also performed significantly worse than the other techniques at final follow-up. The techniques also provided comparable gains in T1-S1 height immediately postoperatively (mean [95% CI] 10.7% [8.4%-13.0%]); however, TGR performed better at final follow-up (21.4% [18.7%-24.1%]). Complications were not significantly different among the patients who underwent the Shilla, TGR, MCGR, and VEPTR techniques, except for the rate of infections. The TGR technique had the lowest rate of unplanned reoperations (mean [95% CI] 15% [10%-23%] vs 24% [19%-29%]) but the highest number of planned reoperations per patient (5.31 [4.83-5.82]). The overall certainty was also low, with a high risk of bias across studies.

CONCLUSIONS

This analysis suggested that the Shilla technique was associated with a greater early coronal Cobb angle correction, whereas use of VEPTR was associated with a lower correction rate at any time point. TGR offered the most significant height gain at final follow-up. The complication rates were comparable across all surgical techniques. The optimal surgical approach should be tailored to individual patients, taking into consideration the strengths and limitations of each option.

Rib-based Distraction Device Implantation Before Age 3 Associated With Higher Unplanned Rate of Return to the Operating Room

BACKGROUND

Surgical treatment of early-onset scoliosis (EOS) with rib-based implants such as the vertical expandable prosthetic titanium rib (VEPTR) is associated with a high rate of complications including surgical site infection, skin breakdown, and implant migration. Many of these complications warrant the need for unplanned reoperations, increasing the burden on an already vulnerable patient population, and introducing the further risk of infection. To provide insight into the risks of early intervention, we investigate the relationship between initial device implantation before the age of 3 and the rate of unplanned reoperation.

METHODS

A retrospective review was performed of all patients at a single institution who had undergone VEPTR insertion for EOS with at least a 2-year follow-up from 2007 to 2016. Patients were stratified into the case-cohort (0 to 2 y of age) or the comparison cohort (3 to 10 y of age) based on age at the time of device implantation. Multivariate regression accounting for age and scoliosis etiology was performed to identify factors predictive of unplanned reoperation.

RESULTS

A total of 137 of 185 patients treated with VEPTR were identified with 76 (56%) undergoing at least 1 unplanned reoperation during the study time period. There were 68 and 69 patients in the age 0- to 2-year and 3- to 10-year cohorts, respectively. Patients aged 0 to 2 years underwent a higher number of total procedures compared with those aged 3 to 10 (13.1±6.5 vs. 10.6±4.8, P=0.032). A significant difference was found in the rate of unplanned reoperation between the 2 cohorts with 44 (65%) patients aged 0 to 2 and 32 (46%) patients aged 3 to 10 undergoing at least 1 unplanned reoperation (P=0.031). Binary logistic multivariate regression accounting for age and scoliosis etiology demonstrated that patients aged 0 to 2 had a significantly greater odds of undergoing an unplanned reoperation (odds ratio=3.050; 95% confidence interval: 1.285-7.241; P=0.011) compared with patients aged 3 to 10 years.

CONCLUSION

Overall, EOS patients aged 0 to 2 at initial VEPTR implantation are up to 3 times higher risk of undergoing an unplanned reoperation compared with those aged 3 to 10.

LEVEL OF EVIDENCE

Level III.

Efficacy of distal pedicle screw fixation as a caudal foundation in VEPTR growing rod constructs for early onset scoliosis

PURPOSE

Surgical treatment of Early Onset Scoliosis (EOS) is challenging. Stable and robust foundations are vital. We have assessed a small cohort of patients with a rib-based proximal fixation and a pedicle screw-based distal foundation for a distraction based growing rod system.

METHOD

This is a single center study in a tertiary spinal deformity unit with a catchment population of over 6 million. We performed a retrospective radiographic evaluation of 15 patients with EOS treated with Vertical Expandable Titanium Prosthetic Rib (VEPTR) implant between 2007 and 2017. The review of medical records and imaging data was performed to identify growth of the spine and complications with pedicle screws.

RESULTS

There were ten male and five female patients with an average age at index surgery of 4yrs 11 months. Mean length of follow-up was 6 yrs 9 months. Serial radiographs revealed improvements in mean Cobb angle of 12 degrees, T1-T12 height of 29 mm and T1-S1 height of 48 mm with no deterioration in distal LIV tilt angle. We report that none of these patients had any complications related to their pedicle screws including cut-out.

CONCLUSION

We report a technique which is efficacious and provides a mechanically robust distal fixation for VEPTR lengthening in early onset scoliosis.

Vertebral body changes after continuous spinal distraction in scoliotic children

PURPOSE

Growth-friendly spinal implants (GFSI) were established for scoliotic children as an interim solution until definite spinal fusion could be performed during puberty. While deformity control was clearly proven, the effects on vertebral shape and morphology are still unclear. Our prospective study assesses the effect of GFSI with continuous distraction on vertebral body shape and volume in SMA children in comparison with previously untreated age-matched SMA patients.

METHODS

Cohort I (n = 19, age 13.2 years) were SMA patients without prior surgical scoliosis treatment. Cohort II (n = 24, age 12.4 years) were children, who had continuous spinal distraction with GFSI for 4.5 years. Radiographic measurements and computed tomography (CT) 3D volume rendering were performed before definite spinal fusion. For cohort II, additional radiographs were analyzed before the first surgical implantation of GFSI, after surgery and every year thereafter.

RESULTS

Our analysis revealed decreased depth and volume in scoliotic patients with prior GFSI compared to scoliotic patients without prior implants. This difference was significant for the lower thoracic and entire lumbar spine. Vertebral body height and pedicle size were unchanged between the two cohorts.

CONCLUSION

CT data showed volume reduction in the vertebral body in scoliotic children after GFSI treatment. This effect was more severe in the lumbar and lower thoracic area. While vertebral height was identical in both groups, vertebral depth was reduced in the GFSI-treated group. Reduced vertebral depth and altered vertebral morphology should be considered before instrumenting the spine in previously treated scoliotic SMA children.

LEVEL OF EVIDENCE III

Diagnostic: individual cross-sectional studies with consistently applied reference standard and blinding.

Complications of dual growing rod with all-pedicle screw instrumentation in the treatment of early-onset scoliosis

BACKGROUND

Treatment of early-onset scoliosis (EOS) is still a challenge to patients, families, and surgeons. Previous studies have indicated that EOS patients are at high risk for complications following growth-friendly surgery. This study was performed to evaluate the results and complications of all-pedicle screw dual growing rod instrumentation in the treatment of EOS.

METHODS

In an IRB-approved retrospective study, we searched the electronic medical records of our institution for all patients who underwent posterior spinal instrumentation for scoliosis between March 2014 and March 2017. Patients under the age of 10 at the time of surgery who were treated with a growth-friendly technique were then selected. Patients with incomplete records and less than 2 years of follow-up were excluded. Charts, operative notes, clinic visits, and radiographs were extracted. Radiographs were reviewed, and the main curve Cobb angle, thoracic kyphosis, pelvic tilt, pelvic incidence, sacral slope, and proximal junctional angles were measured. We specifically looked for any intra-operative or post-operative complications. Statistical analysis was performed to determine the risk factors of complications.

RESULTS

A total of 42 patients with a mean age of 4.8 ± 2.1 years (range, 1.5-8 years) were included in the final analysis. Patients were followed for a median of 34 months (range, 24-55). The major curve was corrected from a mean of 42.9° ± 10.7° to 28.8° ± 9.6° at the latest follow-up. Proximal junctional angles and thoracic kyphosis increased significantly during the follow-up period (both P values < 0.001). A total of 7 complications (17%) were observed. Four patients (10%) developed superficial surgical site infections, all of which resolved with antibiotics and one round of surgical debridement. Three cases (7%) of proximal junctional kyphosis (PJK) were encountered during the study period, none of which required revision surgery. Pre-operative thoracic kyphosis was the only significant risk factor for the development of PJK.

CONCLUSIONS

Our findings suggest that in settings without access to magnetically controlled growing rods, dual growing rods with all-pedicle screw instrumentation is still a viable treatment strategy with comparable results and complications. The most common complications are infection and PJK, with the latter being associated with a larger pre-operative thoracic kyphosis.

Complications in the treatment of EOS: Is there a difference between rib vs. spine-based proximal anchors?

INTRODUCTION

Currently, there is significant equipoise regarding the selection and placement of growing spinal instrumentation when treating patients with early-onset scoliosis (EOS). The primary purpose of this study was to compare complications following surgery in patients receiving rib-based versus spine-based proximal anchors as a part of posterior growing instrumentation in the management of EOS.

METHODS

Retrospective cohort study. Inclusion criteria required: age 3-10 years old, diagnosis of EOS, treatment with a growing construct that utilized rib- or spine-based proximal anchors, and a major coronal curve larger than 40 degrees. The primary outcome analyzed was postoperative complications. Secondary outcomes included coronal major curve correction and patient reported outcomes measured by the Early-Onset Scoliosis 24-item Questionnaire (EOSQ-24). Subjects were categorized into rib- or spine-based proximal fixation groups for comparison.

RESULTS

Of 104 patients included in the study, 76 (73.1%) were treated with rib-based constructs and 28 (26.9%) were treated with spine-based constructs. 24 (31.6%) patients with rib-based constructs and 9 (32.1%) patients with spine-based constructs experienced at least one implant related complication (p = 0.956). Rod fracture was observed more often in spine-based groups than rib-based groups for both patients with congenital/idiopathic EOS (rib: 0 (0%) vs. spine: 3 (13.6%), p = 0.009) and neuromuscular/syndromic EOS (rib: 0 (0%) vs. spine: 2 (33.3%), p = 0.002). Furthermore, surgical site infection was found to be more frequent in rib-based than spine-based groups for neuromuscular/syndromic patients (rib: (13) 27.15 vs. spine: (1) 4.5%, p = 0.029). The most commonly reported complication was device migration. In patients with rib-based constructs, 2 (12.5%) patients with ≥ 5 anchors and 13 (21.7%) patients with < 5 anchors experienced device migration (p = 0.413). In patients with spine-based constructs, 1 (11.1%) patient with ≥ 5 anchors and 4 (21.1%) patients with < 5 anchors experienced device migration (p = 0.064). Spine-based anchors had significantly higher% correction (42.0%) compared to rib-based anchors (20.6%) (p = 0.003) at the most recent follow-up. There were no significant differences in the change of patient reported outcomes as measured by the EOSQ-24 between patients who received rib or spine-based anchors.

DISCUSSION

The number of patients with at least one implant related complication was similar between the rib- and spine-based groups. Having 5 or more proximal anchors appeared protective against proximal device migration; however, this result was not statistically significant. Spine-based anchors had better overall correction than rib-based anchors. There were no differences in the change in patient reported outcomes between spine- and rib-based cohorts.

Can We Save the Implant: Rib-based Implant Removal Rates and Risk Factors Following Irrigation and Debridement (I&D) Surgery?

BACKGROUND

In the event of a surgical site infection, management includes surgical debridement in an attempt to treat the infection and retain the implant; however they are often unsuccessful in this regard. Although studies have described the incidence of complications, current literature does not have sufficient evidence to provide clear recommendations regarding retention versus removal of implants. This study aims to identify predictive factors associated with the need for implant removal to decrease unnecessary attempts at implant retention.

METHODS

A retrospective review of early-onset scoliosis patients at a single institution treated with rib-based vertical expandable prosthetic titanium rib implants who developed infection requiring irrigation and debridement (I&D) due to wound problems including surgical site infection, skin slough, and wound dehiscence. All patients had a minimum of a 2-year follow-up. Univariate and multivariate logistic regression analyses were conducted to determine the odds of implant removal.

RESULTS

Fifty-nine of 181 patients (32%) required an I&D due to a wound problem. These patients underwent the initial implant procedure at a mean age of 4.6±3.8 years. In total, 29 patients ultimately underwent implant removal. Significant predictive factors for removal included total number of wound problems, total number of I&Ds, days from identification of wound problem to I&D procedure, days on antibiotics, total number of surgeries, presence of gastrostomy tube, and nonambulatory status (P<0.0001, 0.001, 0.095, 0.093, 0.082, 0.054, and 0.026, respectively). Multiple logistic regression results indicated a total number of wound problems [odds ratio (OR): 6.00, P=0.001], average days from identification of wound problem to I&D (OR: 1.03, P=0.039), and presence of a gastrostomy tube (OR: 5.7, P=0.07) as independent predictors for implant removal.

CONCLUSIONS

Data suggests that time from the onset of signs of infection until debridement surgery inversely correlates with the ability to retain the implants. In addition, gastrostomy tube and history of previous wound infections may be predictive clinical factors for implant removal in patients with a rib-based vertical expandable prosthetic titanium rib instrumentation. Such information can be useful for clinicians in deciding on whom to attempt implant retention versus removal when a wound problem presents itself.

LEVEL OF EVIDENCE

Level III.

Lengthening Less Than 7 Months Leads to Greater Spinal Height Gain With Rib-based Distraction

BACKGROUND

Severe early-onset scoliosis (EOS) has been associated with a multitude of comorbidities, chief among them being deficient thoracic spine growth and pulmonary complications. EOS management with rib-based instrumentation involves repeated lengthening. Despite expansion practice patterns, there is limited literature and no evidence-based guidelines for optimal expansion intervals. Our study evaluates clinical outcomes in relation to lengthening intervals with the aim of optimizing the timing of surgical expansion in EOS patients.

METHODS

A single-institution retrospective review of 60 EOS patients treated with rib-based growth instrumentation with a minimum of 3-year follow-up and 3 expansion/revision surgeries. Patients were separated into 2 expansion cohorts: (1) more frequent lengthening [MFL group (≤7 mo)] and (2) less frequent lengthening [LFL group (>7 mo)]. Demographic information and clinical factors were recorded. Univariate and bivariate analyses were performed.

RESULTS

Both the MFL group (35 patients) and LFL group (25 patients) were similar in sex distribution, diagnosis, preoperative parameters of interest, and treatment duration. The mean follow-up was 6.0 years. There was an increase in postoperative T1-S1 spine height gained in the MFL group (P=0.006) as well as a higher percent expected spine growth based on normative values (P=0.03) when compared with the LFL group. The MFL group had more expansion/revision surgeries (P=0.003) but no increase in the number of complications (P=0.86).

CONCLUSIONS

More frequent lengthenings were associated with statistically significant overall spinal height gain and percent expected growth without a significant increase in complication rates. It was shown that change in major curve and space available for the lungs was not associated with the lengthening intervals.

LEVEL OF EVIDENCE

Level III-a comparative retrospective study.

Impact of growth friendly interventions on spine and pulmonary outcomes of patients with spinal muscular atrophy

PURPOSE

Patients with spinal muscular atrophy (SMA) are often treated with growth friendly devices such as vertical expandable prosthetic titanium rib(VEPTR) and magnetically controlled growing rods(MCGR) to correct spinal deformity and improve pulmonary function. There is limited data on this topic, and the purpose of this study was to assess the effect of these constructs and the addition of chest wall support (CWS) on spinal deformity, thorax morphology and pulmonary outcomes.

METHODS

This is a retrospective analysis of prospectively collected data. We included patients with chest wall deformity and scoliosis secondary to SMA who were treated with growth friendly interventions and had two-year follow-up. Descriptive statistics and univariate analyses were performed.

RESULTS

This study included 66 patients (25% MCGR, 73% VEPTR, 2% unknown). Approximately 23% of constructs included CWS. The average Cobb angle improved from 67° (SD: 27°) to 50° (SD: 26°) at 2 years in patients with CWS (p = 0.02), and from 59° (SD: 20°) to 46° (SD: 15°) at 2 years in patients without CWS (p < 0.01). Hemithorax height improved in patients treated with and without CWS (p = 0.01), but hemithorax width only improved in patients with CWS (p = 0.01). One patient with CWS and two patients without CWS required additional respiratory support at 2 years. The rates of postoperative complications were not significantly different in patients treated with and without CWS (p = 0.31).

CONCLUSIONS

Growth friendly constructs improve spinal deformity and may be effective in altering the progression toward respiratory failure in patients with SMA. Patients treated with CWS have significant improvements in thorax morphology compared to patients without CWS.

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

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

VEPTR Treatment of Early Onset Scoliosis in Children Without Rib Abnormalities: Long-term Results of a Prospective, Multicenter Study

BACKGROUND

In 2007, this prospective study on vertical expandable prosthetic titanium rib (VEPTR) treatment of early onset scoliosis in children without rib abnormalities was initiated. Two-year follow-up results have previously been reported. This study examines whether, at 5-year follow-up, VEPTR continues to control scoliosis and allow spinal growth.

METHODS

A prospective, multicenter, observational cohort design was used. Patients underwent traditional VEPTR implantation ≥5 years before analysis. Preimplantation and last available images were compared, regardless of whether VEPTR remained in vivo. Additional analysis was performed if VEPTR was in vivo ≥5 years.

RESULTS

This study included 59 patients (mean age at VEPTR implantation, 6.1±2.4 y; mean follow-up, 6.9±1.4 y). Currently, 24 patients still have VEPTR, whereas 24 have converted (13 fusions, 6 MCGR, 3 growing rods, 1 hybrid, and 1 Shilla). Three have had VEPTR explanted, 6 are unknown, and 2 have deceased. On last available imaging (n=59; mean follow-up, 4.8±1.9 y), scoliosis improved from 71.8±18.0 degrees preoperatively to 60.9±20.3 degrees (P<0.001) and T1- T12 height increased (15.8±3.2 to 19.3±3.8 cm, P<0.001). T1-S1 height also increased (24.8±4.4 to 31.2±5.3 cm, P<0.001), representing 119% age-matched growth. Composite improvement of scoliosis, T1-T12, and T1-S1 height was achieved in 79% of patients. A subset of 29 patients with VEPTR was analyzed at most recent follow-up ≥5 years while VEPTR remained in vivo (24 patients with VEPTR above, and 5 who later converted to other devices). Mean age at implantation was 5.0±2.2 years, with a mean VEPTR treatment duration of 6.2±1.1 years. Scoliosis improved from preoperatively (69.3±14.5 to 61.6±16.1 degrees, P=0.006), with mild recurrence from postoperative to 5 years. T1-T12 height increased (15.0±3.3 to 18.7±3.3 cm, P<0.001) and T1-S1 height increased (23.7±4.5 to 30.1±4.6 cm, P<0.001), representing 83% age-matched growth. Composite improvement was achieved in 83% of patients. Instrumented sagittal length also increased during this period (21.8±4.2 to 30.3±5.1 cm, P<0.001).

CONCLUSION

At a 5-year follow-up, VEPTR continues to control scoliosis and allow spinal growth.

LEVEL OF EVIDENCE

Level II-prospective cohort, therapeutic study.

Unplanned return to operation room (OR) following growing spinal constructs (GSCs) in early onset scoliosis (EOS)-a multi-centric study

PURPOSE

To evaluate the incidence and risk factors associated with the unplanned return to OR in EOS.

METHODS

Medical records of 51 patients of EOS operated at three different centres using various types of GSCs were evaluated for complications requiring unplanned surgeries. Data were analysed to find out rate of unplanned surgeries in relation to the aetiology, age and Cobb angle at index surgery, type of implant, cause of unplanned surgery, and management required.

RESULTS

Out of 51 patients, three did not meet inclusion criteria. Forty-eight patients of EOS operated by GSCs with a mean age of 6.7 years (range 2-12 years) with an average follow-up of 67.3 months were studied. There were 30 congenital, 10 idiopathic, 4 syndromic, and 4 neuromuscular cases. Thirty-nine out of 48 patients had one or more unplanned surgeries on follow-up (81.25%). Out of total 248 surgeries following index procedure, 82 were unplanned surgeries (33.06%), including 53 implant revisions, 12 implant-removal, 14 debridement, and 2 flaps. The common complications were 24.14% rod/screw breakage, 42.53% anchor pull-out, 16.09% infections, 6.90% wound dehiscence, and 4.6% neuro deficits. Unplanned surgeries were significantly higher in syndromic (58.8%) and neuromuscular (52.9%) than congenital (27.2%) and idiopathic (37.8%) cases (p < 0.05). Age at index procedure < 5 years had higher unplanned surgeries than age > 5 years (2.5 and 1.23 per patient, respectively,  p < 0.05). Type of implant and initial Cobb angle did not significantly affect the rate of unplanned surgeries (p  > 0.05) CONCLUSION: GSCs in EOS require a frequent revisit to operation room which should be well understood by the surgeon and parents.

Growing rod technique with prior foundation surgery and sublaminar taping for early-onset scoliosis

OBJECTIVE

The aim of this study was to show the surgical results of growing rod (GR) surgery with prior foundation surgery (PFS) and sublaminar taping at an apex vertebra.

METHODS

Twenty-two early-onset scoliosis (EOS) patients underwent dual GR surgery with PFS and sublaminar taping. PFS was performed prior to rod placement, including exposure of distal and proximal anchor areas and anchor instrumentation filled with a local bone graft. After a period of 3-5 months for the anchors to become solid, dual rods were placed for distraction. The apex vertebra was exposed and fastened to the concave side of the rods using sublaminar tape. Preoperative, post-GR placement, and final follow-up radiographic parameters were measured. Complications during the treatment period were evaluated using the patients' clinical records.

RESULTS

The median age at the initial surgery was 55.5 months (range 28-99 months), and the median follow-up duration was 69.5 months (range 25-98 months). The median scoliotic curves were 81.5° (range 39°-126°) preoperatively, 30.5° (range 11°-71°) after GR placement, and 33.5° (range 12°-87°) at the final follow-up. The median thoracic kyphotic curves were 45.5° (range 7°-136°) preoperatively, 32.5° (range 15°-99°) after GR placement, and 42° (range 11°-93°) at the final follow-up. The median T1-S1 lengths were 240.5 mm (range 188-305 mm) preoperatively, 286.5 mm (range 232-340 mm) after GR placement, and 337.5 mm (range 206-423 mm) at the final follow-up. Complications occurred in 6 patients (27%). Three patients had implant-related complications, 2 patients had alignment-related complications, and 1 patient had a wound-related complication.

CONCLUSIONS

A dual GR technique with PFS and sublaminar taping showed effective correction of scoliotic curves and a lower complication rate than previous reports when a conventional dual GR technique was used.

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

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

Early Childhood Scoliosis Management by Vertical Expandable Prosthetic Titanium Rib (VEPTR): Experience of Royal Medical Services (RMS)

Introduction:

Scoliosis could develop at the childhood age and progress beyond skeletal maturity. An early spinal fusion arrests growth of the spine and thorax, risking the development of secondary thoracic insufficiency syndrome. Vertical expandable prosthetic titanium rib (VEPTR) is a fusionless technique aiming to correct the deformity with preservation of growth potential.

Aim:

To show our experience and results regarding the use of VEPTR in children with scoliosis in regard to coronal profiles(length and deformity angle), spinal growth, and the complications we faced during the follow-up of two years after the index procedure.

Methods:

A retrospective analysis of prospectively collected data of a case series. Forty child with scoliosis of different etiologies. Their primary diagnoses were neuromuscular scoliosis in 13, Juvenile idiopathic scoliosis in12, Congenital Scoliosis in 8, syndromatic patients 5 and 2 with Arthrogryposis. All 40 patients received percutaneous rib-to-pelvis or rib to vertebra or rib to rib VEPTR implantation between January 2016 and January 2018. None of them needed blood transfusion. They underwent 56 primary implantation, 16(40%) bilateral system and 24(60%) unilateral followed by lengthening procedure in a period of 4-6 months. The patients were assessed based on mechanical measures, that is, the radiographic improvement of their scoliosis, spinal height, and sagittal and coronal correction, which are measured and compared preoperatively, immediately postoperatively and at two years follow up, complication encountered during this period are also counted.

Results:

The average initial correction in Cobb angle immediately after the index surgery was 14.4° (5°-26°) and the average final correction of Cobb which is measured after the last expansion procedure (Cobb angle of the major curve measured after last expansion minus initial preoperative Cobb angle of the major curve) was 7.3° (12%). The average of preoperative coronal T1-S1 length was 25.6 cm with an average initial correction achieved immediately after implantation of VEPTR of2.8 cm (1.2-5.1cm) which is 10.9%, and the average coronal length gain at 2 years follow up was 5.7 cm (3.7-9.8cm) that is 22.2%. Complication occurred in 18 of our patients (45%).

Conclusion:

Early results of VEPTR for childhood scoliosis are encouraging. Follow-up till skeletal maturity will best determine future indications.

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.

[Surgical "no-touch" distraction technique to correct pediatric scoliosis]

OBJECTIVE

Reduction and retention of the scoliotic curve in children with progressive spinal deformities.

INDICATIONS

Progressive neuromyopathic scoliosis which cannot be controlled conservatively (especially by walking disability), and/or development of a thorax insufficiency syndrome (TIS).

CONTRAINDICATIONS

Insufficient soft tissue coverage; body weight < 11.4 kg; body mass index (BMI) > 25 or >50 kg; missing osseous anchoring structures (ribs); adult skeleton (usually age < 12 years at surgery); severe spasticity.

SURGICAL TECHNIQUE

Indirect correction and distraction of the spinal deformity by two extendable, paravertebral telescopic implants, anchored to the cranial ribs and the iliac crest; the spine is not compromised surgically.

POSTOPERATIVE MANAGEMENT

Early functional therapy, no brace; multiple surgical (VEPTR®-system) or externally (magnetically controlled rods) controlled extensions per year.

RESULTS

The surgical paravertebral "no-touch" technique for spine correction is particularly suitable for children with neuromyopathic scoliosis with a body weight > 11.4 kg. Our prospective group of children (n = 45), was treated with a combination of the classic vertical expandable prosthetic titanium rib (VEPTR®) anchored to the ribs and iliac crest combined with a magnetically controlled telescopic implant (MAGEC®). The primary correction of >50% was achieved, while progression was effectively prevented over years. In 495 outpatient lengthening procedures, the rate of implant-associated complications requiring surgery was 3.7%. Of the 45 children, 13 (29%) underwent surgical revision. With the proposed surgical "no-touch" technique for scoliosis correction of pediatric neuromyopathic deformities, an effective reduction of the scoliotic curve can be achieved and maintained. Advantages of the method are a partial retention of spinal flexibility and a reduction of spinal ossifications, which facilitates dorsal spondylodesis as the final treatment.

VEPTR: Are We Reducing Respiratory Assistance Requirements?

BACKGROUND

The assisted ventilation rating (AVR) indicates the degree of external respiratory support required in children with thoracic insufficiency syndrome (TIS) and early onset scoliosis. For skeletally immature patients with TIS, the vertical expandable prosthetic titanium rib (VEPTR) device can be used to improve lung volume and growth. We hypothesized that patients who underwent early thoracic reconstruction by VEPTR treatment had an improved respiratory status.

METHODS

Preoperative and postoperative AVR ratings were prospectively collected in a multicenter study group and compared to determine change after VEPTR treatment. Patients under 10 years of age at initial implant with minimum of 2-year follow-up data were included. Patients were excluded if there were incomplete data or if initial AVR was normal (breathing on room air). Statistical analysis was performed on groups which had stable, declined, and improved AVR at final follow-up.

RESULTS

Database search yielded 77 patients with initial abnormal AVR. Average follow-up was 5.6 years. The most frequent primary diagnoses were congenital scoliosis (n=14) and spinal muscular atrophy (n=14). In total, 19 (24%) demonstrated improvement, 9 (12%) patients deteriorated, and 49 (64%) remained at the same level. The average preoperative major curve in those with improvement (58.4 degrees) and those with no change (63.5 degrees) was less than in those with deterioration (85.5 degrees) (P=0.014). The average age in years at implant of those with improvement (4) was less than those declined (6.7) and those with no change (5.5). In total, 16 (84.2%) of those that improved had a normal AVR and did not require respiratory support at last follow-up.

CONCLUSIONS

There is evidence that a subset of patients with early onset scoliosis and TIS who received early thoracic reconstruction with VEPTR treatment show complete resolution of pulmonary support at final follow-up. In total, 89% of 79 patients did not experience respiratory deterioration. A total of 24% (n=19) had a positive change with over 84% (n=16) of this group no longer requiring support.

LEVEL OF EVIDENCE

Level III-prognostic.

Spinal instrumentation in infants, children, and adolescents: a review

OBJECTIVEThe evolution of pediatric spinal instrumentation has progressed in the last 70 years since the popularization of the Harrington rod showing the feasibility of placing spinal instrumentation into the pediatric spine. Although lacking in pediatric-specific spinal instrumentation, when possible, adult instrumentation techniques and tools have been adapted for the pediatric spine. A new generation of pediatric neurosurgeons with interest in complex spine disorder has pushed the field forward, while keeping the special nuances of the growing immature spine in mind. The authors sought to review their own experience with various types of spinal instrumentation in the pediatric spine and document the state of the art for pediatric spine surgery.METHODSThe authors retrospectively reviewed patients in their practice who underwent complex spine surgery. Patient demographics, operative data, and perioperative complications were recorded. At the same time, the authors surveyed the literature for spinal instrumentation techniques that have been utilized in the pediatric spine. The authors chronicle the past and present of pediatric spinal instrumentation, and speculate about its future.RESULTSThe medical records of the first 361 patients who underwent 384 procedures involving spinal instrumentation from July 1, 2007, to May 31, 2018, were analyzed. The mean age at surgery was 12 years and 6 months (range 3 months to 21 years and 4 months). The types of spinal instrumentation utilized included occipital screws (94 cases); C1 lateral mass screws (115 cases); C2 pars/translaminar screws (143 cases); subaxial cervical lateral mass screws (95 cases); thoracic and lumbar spine traditional-trajectory and cortical-trajectory pedicle screws (234 cases); thoracic and lumbar sublaminar, subtransverse, and subcostal polyester bands (65 cases); S1 pedicle screws (103 cases); and S2 alar-iliac/iliac screws (56 cases). Complications related to spinal instrumentation included hardware-related skin breakdown (1.8%), infection (1.8%), proximal junctional kyphosis (1.0%), pseudarthroses (1.0%), screw malpositioning (0.5%), CSF leak (0.5%), hardware failure (0.5%), graft migration (0.3%), nerve root injury (0.3%), and vertebral artery injury (0.3%).CONCLUSIONSPediatric neurosurgeons with an interest in complex spine disorders in children should develop a comprehensive armamentarium of safe techniques for placing rigid and nonrigid spinal instrumentation even in the smallest of children, with low complication rates. The authors' review provides some benchmarks and outcomes for comparison, and furnishes a historical perspective of the past and future of pediatric spine surgery.

Expansion Thoracoplasty as a Life-Saving Procedure in an Adolescent With Severe Spinal Deformity and Sacral Agenesis

STUDY DESIGN

Case report.

OBJECTIVES

To describe use of expansion thoracoplasty (ET) for severe thoracic insufficiency syndrome (TIS) in an adolescent with severe spinal deformity.

BACKGROUND

ET is typically performed in young patients with TIS to increase chest cavity volume, improve alveolar expansion, and potentially improve alveolar proliferation. ET has not been well-described in adolescent patients with TIS.

METHOD

A mature adolescent with previously treated myelokyphosis and sacral agenesis developed severe TIS with dependence on supplemental oxygen and noninvasive ventilation. She was treated with two-stage bilateral ET and vertical expandable prosthetic titanium rib (VEPTR) placement. Yearly pulmonary function testing (PFT) was performed over 7 years of follow-up.

RESULTS

Significant clinical pulmonary improvement was achieved and maintained at final follow-up, as the patient no longer required supplemental oxygen. Percentage predicted forced vital capacity (FVC) improved from 29% to 36%; percentage predicted forced expiratory volume-1 second (FEV1) improved from 30% to 36%.

CONCLUSIONS

This case demonstrates that improvement and stabilization of respiratory function can be achieved with instrumented ET in a skeletally mature adolescent with severe TIS and spinal deformity.

Use of a Vertical Expandable Prosthetic Titanium Rib in Children With Thoracic Insufficiency Syndrome and Scoliosis

Thoracic insufficiency syndrome is the inability of the thorax to support normal respiration or lung growth. One treatment to address the thoracic deformities associated with the syndrome is placement of a vertical expandable prosthetic titanium rib. The goal is to restore thoracic volume, symmetry, and function and to allow for growth of the thorax in skeletally immature children. The main topics include indications for placement of a titanium rib, postoperative nursing care, potential complications, long-term follow-up, quality-of-life issues, and implications for critical care nurses and advanced practice nurses.

Pediatric spine imaging post scoliosis surgery

Many orthopedic articles describe advances in surgical techniques and implants used in pediatric scoliosis surgery. However, even though postoperative spine imaging constitutes a large portion of outpatient musculoskeletal pediatric radiology, few, if any, radiology articles discuss this topic. There has been interval advancement over the last decades of the orthopedic procedures used in the treatment of spinal scoliosis in adolescents with idiopathic scoliosis. The goal of treatment in these patients is to stop the progression of the curve by blocking the spinal growth and correcting the deformity as much as possible. To that end, the authors in this paper discuss postoperative imaging findings of Harrington rods, Luque rods, Luque-Galveston implants and segmental spinal fusion systems. Regarding early onset scoliosis, the guiding principles used for adolescent idiopathic scoliosis do not apply to a growing spine because they would impede lung development. As a result, other devices have been developed to correct the curve and to allow spinal growth. These include spine-based growing rods, vertically expandable prosthetic titanium rods (requiring repetitive surgeries) and magnetically controlled growing rods (with a magnetic locking/unlocking system). Other more recent systems are Shilla and thoracoscopic anterior vertebral body tethering, which allow guided growth of the spine without repetitive interventions. In this paper, we review the radiologic appearances of different orthopedic implants and techniques used to treat adolescent idiopathic scoliosis and early onset scoliosis. Moreover, we present the imaging findings of the most frequent postoperative complications.

Is Asphyxiating Thoracic Dystrophy (Jeune's Syndrome) Deadly and Should We Insist on Treating It? Reconstructive Surgery "On Demand"

Our aim is to present the treatment of one of the skeletal manifestations of Jeune's syndrome (JS), the hypoplastic chest, which can result in thoracic insufficiency syndrome and present "on-demand" stage surgical technique using mandible locking plate system for the fixation of ribs. The diagnosis "Jeune's syndrome" was presented clinically in a 3-month-old girl from a family in which the first child died of JS at the age of 18 months. After close follow-up for several months and preoperative planning, we decided to make reconstructive chest operation with atypical use of a double-angled mandible locking plate for fixation. The plate was shaped as a "crown" to ensure the three dimension stability, from the dorsal part of the most curved ribs (paravertebrally) to the sternum after the resection of this area. Operation was done at the period of worsened breathing. For nearly 1 year, the rib cage preserved its stability and the child was in good condition. During the next 3 months, the upper part of the deformation started to grow inward fast. Second operation was "on demand," and the implants used were mandible locking plates curved anterolaterally to effectuate extension of the rib cage and the sternum. In both the reconstructive operations, we spared the rectus and pectoral muscles and achieved good enlargement of the thoracic volume. The postoperative period is smooth and the child is active, without complications. We believe that in the future, the treatment should be "on demand" according to the course of the illness and the results of the follow-up examinations and adequate to the progress of chest wall deformity.

Poland Syndrome: Use of Vertical Expandable Prosthetic Titanium Rib System before Walking Age-A Case Report

Aim  To present a new therapy for Poland syndrome (PS) using a novel surgical approach: the vertical expandable prosthetic titanium rib (VEPTR) system. Methods  The VEPTR system rib-to-rib variant was used to enhance the chest wall and vertebral column support in a young patient before walking age. Case Report  We present a 12-month-old infant diagnosed with left-sided PS at the age of 6 months associated with missing ribs, scoliosis, and absence of the left pectoral muscles. Because of four missing ribs, paradoxical breathing was present. In addition, the left scapula was protruding into the chest due to the missing rib support. Scoliosis was caused by a left-sided nonsegmented bar of the thoracic spine. Results  We decided to use the VEPTR system before the patient reached walking age to prevent progression of column deformation and future pulmonary problems. To improve the spinal deformity, to stabilize the thorax, and to improve thoracic function, we performed the operation at 1 year of age. At 10-month follow-up, the patient was reevaluated. The construction was still stable and scoliosis had not deteriorated. Conclusion  The VEPTR system is a choice of treatment in young patients with PS to prevent late complications after a child reaches walking age.

Biomechanical Evaluation of a Growth-Friendly Rod Construct

BACKGROUND

Distraction-type rods mechanically stabilize the thorax and improve lung growth and function by applying distraction forces at the rib, spine, pelvis, or a combination of locations. However, the amount of stability the rods provide and the amount the thorax needs is unknown.

METHODS

Five freshly frozen and thawed cadaveric thoracic spine specimens were tested for lateral bending, flexion/extension, and axial rotation in displacement control (1°/sec) to a load limit of ±5 Nm for five cycles after which a growth-friendly unilateral rod was placed in a simulated rib-to-lumbar attachment along the right side. The specimens were tested again in the same modes of bending. From the seven Optotrak Orthopedic Research Pin markers (Northern Digital Inc., Waterloo, Ontario, Canada) inserted into the top potting to denote T1, and the right pedicles at T2, T4, T5, T8, T9, and T11 and the Standard Needle Tip Pressure Transducers (Gaeltech, Isle of Skye, Scotland) inserted into the T4/T5 and T8/T9 discs, motion, stiffness, and pressure data were calculated. Parameters from the third cycle of the intact case and the construct case were compared using two-tailed paired t tests with 0.05 as the level of significance.

RESULTS

With the construct attached, the T1-T4 segment showed a 30% increase in neutral zone stiffness during extension (p = .001); the T8-T12 segment experienced a 63% reduction in the in-plane range of motion during flexion (p = .04); and the T8/T9 spinal motion unit had a significant decrease of 24% in elastic zone stiffness during left axial rotation (p = .04).

CONCLUSIONS

It is clear the device as tested here does not produce large biomechanical changes, but the balance between providing desired changes while preventing complications remains difficult.

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

BACKGROUND

Definitive "final" surgical fusion is the common end point for growing-rod treatment of early-onset scoliosis. However, final surgical fusion may be unnecessary for patients who have reached skeletal maturity with good alignment. This study characterizes patients who completed growing-rod treatment but did not undergo final surgical fusion.

METHODS

Using a multicenter early-onset-scoliosis database, we identified 167 patients who received growing-rod treatment from 1995 through 2010, reached skeletal maturity, and had a minimum 2-year follow-up after their last surgery. Thirty patients did not undergo final surgical fusion (observation group) and were compared clinically and radiographically with 137 patients who did undergo final fusion (final surgical fusion group).

RESULTS

No significant differences were found between the groups with regard to the age at which treatment was initiated (p = 0.127), distribution of diagnoses (p = 0.84), or number of lengthening procedures (p = 0.692). In the observation group, 26 patients retained the growing rods and 4 patients had them removed at the last surgery because of infection. The mean primary curve correction at the end of treatment was 48% (from an initial mean magnitude of 79° to a mean final curve of 41°) in the observation group compared with 38% (from 74° to 46°) in the final surgical fusion group. There was no significant difference in final curve magnitude (41° in the observation group and 46° in the final surgical fusion group; p = 0.182). The mean increase in trunk height was 30.5% in the observation group and 35% in the final surgical fusion group. The final trunk height in the observation group was not significantly less than that in the final surgical fusion group (p = 0.142).

CONCLUSIONS

Because of progressive ankylosis, avoiding final surgical fusion at skeletal maturity is a viable option for patients treated with growing rods for all diagnostic subgroups of early-onset scoliosis who have satisfactory final alignment and trunk height, a minimal gain in length at the last distraction, and no clinical or radiographic evidence of implant-related problems.

LEVEL OF EVIDENCE

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

Effects of follower load and rib cage on intervertebral disc pressure and sagittal plane curvature in static tests of cadaveric thoracic spines

The clinical relevance of mechanical testing studies of cadaveric human thoracic spines could be enhanced by using follower preload techniques, by including the intact rib cage, and by measuring thoracic intervertebral disc pressures, but studies to date have not incorporated all of these components simultaneously. Thus, this study aimed to implement a follower preload in the thoracic spine with intact rib cage, and examine the effects of follower load, rib cage stiffening and rib cage removal on intervertebral disc pressures and sagittal plane curvatures in unconstrained static conditions. Intervertebral disc pressures increased linearly with follower load magnitude. The effect of the rib cage on disc pressures in static conditions remains unclear because testing order likely confounded the results. Disc pressures compared well with previous reports in vitro, and comparison with in vivo values suggests the use of a follower load of about 400N to approximate loading in upright standing. Follower load had no effect on sagittal plane spine curvature overall, suggesting successful application of the technique, although increased flexion in the upper spine and reduced flexion in the lower spine suggest that the follower load path was not optimized. Rib cage stiffening and removal both increased overall spine flexion slightly, although with differing effects at specific spinal locations. Overall, the approaches demonstrated here will support the use of follower preloads, intact rib cage, and disc pressure measurements to enhance the clinical relevance of future studies of the thoracic spine.

A comparison of the effects of two different techniques on shoulder balance in the treatment of congenital scoliosis: Vertical expandable prosthetic titanium rib and dual growing rod

PURPOSE

The purpose of this study is to compare the effects of two different growth guidance techniques (dual growing rod and vertical expandable prosthetic titanium rib [VEPTR]) on shoulder balance, in the surgical treatment of congenital scoliosis.

MATERIALS AND METHODS

Thirteen patients who were operated due to congenital scoliosis are divided into two groups. The coracoid height difference and clavicular tilt angle difference were measured on standing anteroposterior X-ray images in the preoperative, early postoperative periods, and during the last follow-up.

RESULTS

Clinical improvement in shoulder balance was obtained in VEPTR during the last follow-up, but there was no significance in the comparison among the two groups during the last follow-up.

CONCLUSION

The effect of the growth guidance techniques on shoulder balance positively contributes in the surgical treatment of congenital scoliosis.

Magnetic resonance imaging in children: common problems and possible solutions for lung and airways imaging

Pediatric chest MRI is challenging. High-resolution scans of the lungs and airways are compromised by long imaging times, low lung proton density and motion. Low signal is a problem of normal lung. Lung abnormalities commonly cause increased signal intenstities. Among the most important factors for a successful MRI is patient cooperation, so the long acquisition times make patient preparation crucial. Children usually have problems with long breath-holds and with the concept of quiet breathing. Young children are even more challenging because of higher cardiac and respiratory rates giving motion blurring. For these reasons, CT has often been preferred over MRI for chest pediatric imaging. Despite its drawbacks, MRI also has advantages over CT, which justifies its further development and clinical use. The most important advantage is the absence of ionizing radiation, which allows frequent scanning for short- and long-term follow-up studies of chronic diseases. Moreover, MRI allows assessment of functional aspects of the chest, such as lung perfusion and ventilation, or airways and diaphragm mechanics. In this review, we describe the most common MRI acquisition techniques on the verge of clinical translation, their problems and the possible solutions to make chest MRI feasible in children.

Congenital scoliosis: an up-to-date

Congenital scoliosis represents a spinal malformation due to defects of formation, segmentation or mixed ones. It is characterized by a longitudinal and rotational imbalance. 54 patients were analyzed and 39 out of them were operated by various approaches with anterior and posterior instrumentations during 2000 and 2012. The impossibility to appoint some patients encountered in the daily practice into the known classifications, allowed us to purpose two categories of congenital scoliosis related to the predominance of spinal deviances in the coronal and transversal views. No certain etiology of congenital scoliosis has been identified until today. The susceptibility of some polygenic defects is obvious due to the presence of a sum of defects associated to most of the congenital scoliosis cases and the rarity of the presence of a unique defect. The diagnosis requires a thorough clinical and imaging examination in order to establish an individualized therapeutic strategy. The treatment of congenital scoliosis is different from the adolescent idiopathic one. Therapeutic criteria are significantly different. It is essential to assess the difference in growth of the concavity related to the convexity when choosing a particular procedure. The magnitude of the curve and the progressive rate are fundamental issues to the surgeon.

Analysis of retrieved growth guidance sliding LSZ-4D devices for early onset scoliosis and investigation of the use of nitinol rods for this system

STUDY DESIGN

Analysis of volumetric wear loss of retrieved growth guidance sliding devices LSZ-4D for treatment of early onset scoliosis and laboratory in vitro wear test for comparison of wear resistance of alloys Nitinol, Ti, and cobalt chromium (CoCr).

OBJECTIVE

To evaluate quantitatively the amount of wear debris from the sliding LSZ-4D device and to investigate the potential of using Nitinol for replacing Ti alloys in spinal instrumentation. To do that, wear resistance of Nitinol, Ti, and CoCr was compared.

SUMMARY OF BACKGROUND DATA

There are little data regarding the amount of wear debris associated with growth guidance sliding devices for patients with early onset scoliosis and the wear resistance of superelastic Nitinol compared with Ti and CoCr.

METHODS

Volumetric wear loss was measured on LSZ-4D devices made from titanium alloy Ti6Al4V and each consisted of 2 rectangular section (6 × 4 mm) rods and 40 ± 8 fixture elements (20 ± 4 hooks and 20 ± 4 clips) retrieved from 3 patients (implantation period, 3.5-5.8 yr). Images of wear scars were taken on Bruker interferometer microscope and incorporated into MATLAB software. Wear resistance of Nitinol, Ti, and CoCr was studied using reciprocation pin-on-disk wear test in bovine serum at 37°C ± 1°C.

RESULTS

The volume wear rate of LSZ-4D device was found to be 12.5 mm per year from which 5 mm³ per year is the wear debris of the rod and 7.5 mm per year is the contribution of fixtures. Wear resistance of Nitinol is 100 times higher than that of Ti and comparable with that of CoCr.

CONCLUSION

Application of wear-resistant coatings on Ti components in growth guidance sliding devices for the treatment of early onset scoliosis will be useful. High wear resistance of Nitinol combined with its superelastic and shape memory properties could make application of Nitinol rods for spinal instrumentation beneficial.

Recent advances in the management of early onset scoliosis

As the undesired results of early spinal fusion have become apparent, "growth-friendly" management methods for early onset scoliosis have been increasing during recent years. Current literature supports the use of repeated corrective cast applications as the initial management for most early onset progressive spinal deformities as either definitive treatment or as a temporizing measure. If casting is not an option or the deformity cannot be controlled via casting, one of the growth-friendly instrumentation techniques is chosen. Growth-friendly surgical methods and implants have been evolving as understanding of the disease improves.

Chest wall abnormalities and their clinical significance in childhood

The thorax consists of the rib cage and the respiratory muscles. It houses and protects the various intrathoracic organs such as the lungs, heart, vessels, esophagus, nerves etc. It also serves as the so-called "respiratory pump" that generates the movement of air into the lungs while it prevents their total collapse during exhalation. In order to be performed these functions depend on the structural and functional integrity of the rib cage and of the respiratory muscles. Any condition (congenital or acquired) that may affect either one of these components is going to have serious implications on the function of the other. Furthermore, when these abnormalities occur early in life, they may affect the growth of the lungs themselves. The following article reviews the physiology of the respiratory pump, provides a comprehensive list of conditions that affect the thorax and describes their effect(s) on lung growth and function.

Pulmonary and Radiographic Outcomes of VEPTR (Vertical Expandable Prosthetic Titanium Rib) Treatment in Early-Onset Scoliosis

BACKGROUND

VEPTR (vertical expandable prosthetic titanium rib) expansion thoracoplasty is used to manage thoracic insufficiency syndrome in early-onset scoliosis. Literature regarding the effects of this technique on pulmonary function is scarce. The aim of this study was to report the intermediate-term results of VEPTR expansion thoracoplasty.

METHODS

Twenty-one children with thoracic insufficiency syndrome underwent VEPTR expansion thoracoplasty from 2002 to 2012 and had complete chart data, preoperative and follow-up radiographs, and pulmonary function tests performed at the index implantation, first expansion, and last expansion. Pulmonary function tests with forced and passive deflation techniques developed for children under general anesthesia were performed prior to the index implantation and each expansion surgery under the same anesthetic conditions. Pulmonary and radiographic parameters were analyzed longitudinally.

RESULTS

Mean follow-up was six years, and mean age at implantation was 4.8 years. The mean number of expansion procedures per patient was eleven, and the mean number of pulmonary function tests was ten. The mean interval between surgical procedures was 6.4 months. Mean forced vital capacity (FVC) increased from 0.65 to 0.96 L (p < 0.0001). However, the percentage of the predicted FVC decreased from 77% to 58%. Respiratory system compliance normalized on the basis of body weight, Crs/kg, decreased by 39%, from 1.4 to 0.86 mL/cm H₂O/kg. The mean Cobb angle before treatment was 80°, and the mean maximum thoracic kyphosis angle was 57° (range, 7° to 107°). The initial coronal correction was maintained at the time of final follow-up (67°); however, there was a trend toward a decrease in the maximum thoracic kyphosis angle (to 66°, p = 0.08). Clinically apparent proximal thoracic kyphosis occurred in four patients, and spinal imbalance occurred in seven. The mean gain in T1-T12 height during the treatment period was 18 mm (2.9 mm/year).

CONCLUSIONS

FVC improved over time; however, this increase in lung volume did not keep up with the growth of the child, as the percentage of the predicted FVC decreased, and the chest wall stiffness increased. Coronal correction was maintained, but the increase in proximal thoracic kyphosis is concerning.

LEVEL OF EVIDENCE

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

Extraspinal ossifications after implantation of vertical expandable prosthetic titanium ribs (VEPTRs)

INTRODUCTION

Though developed for thoracic insufficiency syndrome, the spinal growth-stimulating potential and the ease of placement of vertical expandable titanium ribs (VEPTRs) has resulted in their widespread use for early-onset spine deformity. Observation of implant-related ossifications warrants further assessment, since they may be detrimental to the function-preserving non-fusion strategy.

PATIENTS AND METHODS

Radiographs (obtained pre and post index procedure, and at 4-year follow-up) and the records of 65 VEPTR patients from four paediatric spine centres were analysed. Ossifications were classified as type I (at anchor points), type II (along the central part) or type III (re-ossification after thoracostomy).

RESULTS

The average age at the index procedure was 6.5 years (min 1, max 13.7). The most prevalent spine problem was congenital scoliosis (37) with rib fusions (34), followed by neuromuscular and syndromic deformities (13 and 8, respectively). Idiopathic and secondary scoliosis (e.g. after thoracotomy) were less frequent (3 and 4, respectively). Forty-two of the 65 (65 %) patients showed ossifications, half of which were around the anchors. Forty-five percent (15/33) without pre-existing rib fusions developed a type II ossification along the implant. Re-ossifications of thoracostomies were less frequent (5/34, 15 %). The occurrence of ossifications was not associated with patient-specific factors.

CONCLUSIONS

Implant-related ossifications around VEPTR are common. In contrast to harmless bone formation around anchors, ossifications around the telescopic part and the rod section are troublesome in view of their possible negative impact on chest cage compliance and spinal mobility. This potential side effect needs to be considered during implant selection, particularly in patients with originally normal thoracic and spinal anatomy.

Updates on surgical treatments for pediatric scoliosis

Scoliosis in children poses serious problems including respiratory problems, trunk imbalance, and depression, as well as detracting from the child's appearance. Scoliosis can also contribute to back pain later in life. Advanced surgical techniques allow for good correction and maintenance of progressive curves, and growth-sparing treatments are now available for patients with early-onset scoliosis (EOS). Posterior corrective surgeries using pedicle screw (PS) constructs, which allow curves to be corrected in three dimensions, has become the most popular surgical treatment for scoliosis. Several navigation systems and probes have been developed to aid in accurate PS placement. For thoracolumbar and lumbar curves, anterior surgery remains the method of choice. Growth-sparing techniques for treating EOS include growing rods, the Shilla method, anterior stapling, and vertical expandable prosthetic titanium rib, which was originally designed to treat thoracic insufficiency syndrome. However, these advanced surgical techniques do not always offer a perfect solution for pediatric scoliosis, and they are associated with complications such as infections and problems with instrumentation. Surgeons have developed several techniques in efforts to address these complications. We here review historic and recent advances in the surgical treatment of scoliosis in children, the problems associated with various techniques, and the challenges that remain to be overcome.

Proximal spinal muscular atrophy: current orthopedic perspective

Spinal muscular atrophy (SMA) is a hereditary neuromuscular disease of lower motor neurons that is caused by a defective “survival motor neuron” (SMN) protein that is mainly associated with proximal progressive muscle weakness and atrophy. Although SMA involves a wide range of disease severity and a high mortality and morbidity rate, recent advances in multidisciplinary supportive care have enhanced quality of life and life expectancy. Active research for possible treatment options has become possible since the disease-causing gene defect was identified in 1995. Nevertheless, a causal therapy is not available at present, and therapeutic management of SMA remains challenging; the prolonged survival is increasing, especially orthopedic, respiratory and nutritive problems. This review focuses on orthopedic management of the disease, with discussion of key aspects that include scoliosis, muscular contractures, hip joint disorders, fractures, technical devices, and a comparative approach of conservative and surgical treatment. Also emphasized are associated complications including respiratory involvement, perioperative care and anesthesia, nutrition problems, and rehabilitation. The SMA disease course can be greatly improved with adequate therapy with established orthopedic procedures in a multidisciplinary therapeutic approach.