The vertical expandable prosthetic titanium rib implant for the treatment of thoracic insufficiency syndrome associated with congenital and neuromuscular scoliosis in young children

Pediatric Device Clinical Trials Activity: 1999-2022

OBJECTIVES

This study assessed the state of pediatric medical device (PMD) development by comparing PMD clinical trials to pediatric trials evaluating drugs and biologics, from 1999 to 2022.

METHODS

The site https://www.clinicaltrials.gov was used to identify and quantify both PMD clinical trials and pediatric trials for drugs and biologics. Clinical specialty was also assessed. The institutions included were the 7 children's hospitals primarily affiliated with the Food and Drug Administration (FDA) Pediatric Device Consortia (PDC) grant program between 2018 and 2023. For a national comparison, an additional search assessed PMD trials across all US medical institutions.

RESULTS

A total of 243 PMD clinical trials were identified at the FDA-PDC institutions on the basis of the year of initiation; the average number of PMD trials initiated per year per institution was 1.5 from 1999 to 2022. However, PMD trials significantly increased during the period 2014 to 2022 compared with 1999 to 2013 (P < .001); the rate of initiation of drug and biologic pediatric trials demonstrated no significant differences between these time periods. A national survey of all institutions initiating PMD trials, and drugs and biologics trials, identified 1885 PMD trials out of a total 12 943. A comparable trend was noted in the national survey with initiation of PMD trials increasing significantly from 2014 to 2022 (P < .001), compared with 1999 to 2013, whereas the rate of initiation of drug and biologic trials during these periods did not demonstrate a significant change.

CONCLUSIONS

Although pediatric clinical trial initiation for drugs and biologics remained stable from 1999 to 2022, the rate of new PMD trials significantly increased during the period 2014 to 2022 at FDA-PDC institutions and nationally.

The efficacy of bracing in the treatment of progressive early-onset scoliosis

Serial casting as one of the applications to treat early-onset scoliosis has been reported efficiently to improve deformity, but no report has focused on the efficacy of braces in the treatment of congenital early-onset scoliosis and comparison with progressive idiopathic early-onset scoliosis. Patients with progressive EOS treated with braces in our institution with a minimum of 4 years follow-up were reviewed. Two groups according to the etiological diagnosis were analyzed and compared: the congenital scoliosis (CS) group and idiopathic scoliosis (IS) group. The success cases and the failure cases were also compared. 27 patients with an average main Cobb angle of 38.19° (20-55) underwent initial bracing at an average age of 55.7 months (24-108), the average follow-up time was 76.19 months (49-117). In IS group the main Cobb angle was corrected to 18.69 ± 12.06° (48.61%) following the first bracing; the final Cobb angle was 23.08 ± 22.15°(38.76%) after brace removal. In CS group the main Cobb angle was corrected to 33.93 ± 10.31°(17.1%) following the first bracing and 37.93 ± 14.74°(3.53%) after brace removal. Both coronal chest width and T1-T12 height increased dramatically from pre-bracing to the last follow-up. Patients diagnosed as IS tended to have a better result in main Cobb angle correction than that of CS (P = 0.049). By the time of last follow-up, 8 patients had undergone surgery, and the operation time was postponed by 68.88 ± 26.43 months. For patients with progressive early-onset scoliosis, bracing is an efficient nonsurgical alternative to casting, and some of them can be cured; if not, eventual surgical intervention can be delayed for a period of time without restrictions on the thoracic cavity.

Biomedical Applications of Titanium Alloys: A Comprehensive Review

Titanium alloys have emerged as the most successful metallic material to ever be applied in the field of biomedical engineering. This comprehensive review covers the history of titanium in medicine, the properties of titanium and its alloys, the production technologies used to produce biomedical implants, and the most common uses for titanium and its alloys, ranging from orthopedic implants to dental prosthetics and cardiovascular devices. At the core of this success lies the combination of machinability, mechanical strength, biocompatibility, and corrosion resistance. This unique combination of useful traits has positioned titanium alloys as an indispensable material for biomedical engineering applications, enabling safer, more durable, and more efficient treatments for patients affected by various kinds of pathologies. This review takes an in-depth journey into the inherent properties that define titanium alloys and which of them are advantageous for biomedical use. It explores their production techniques and the fabrication methodologies that are utilized to machine them into their final shape. The biomedical applications of titanium alloys are then categorized and described in detail, focusing on which specific advantages titanium alloys are present when compared to other materials. This review not only captures the current state of the art, but also explores the future possibilities and limitations of titanium alloys applied in the biomedical field.

Surgical Treatment of Spinal Deformities in Pediatric Orthopedic Patients

Scoliosis and Scheuermann's disease are common spinal deformities that affect a substantial population, particularly adolescents, often impacting their quality of life. This comprehensive review aims to present a detailed understanding of these conditions, their diagnosis, and various treatment strategies. Through an extensive exploration of current literature, the review discusses the etiology of these spinal deformities and the use of diagnostic tools such as X-rays and MRI. It further delves into the range of treatment options available, from conservative approaches such as physiotherapy and bracing to more invasive surgical interventions. The review underscores the necessity of an individualized treatment approach, taking into account factors such as the patient's age, the severity of the curvature, and overall health. This all-encompassing perspective on scoliosis and Scheuermann's disease will aid in evidence-based decision making in their management with the goal of improving patient outcomes.

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

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

LEVEL OF EVIDENCE

Level III.

Developments in Congenital Scoliosis and Related Research from 1992 to 2021: A Thirty-Year Bibliometric Analysis

BACKGROUND

Many studies, mainly original articles and reviews, have been reported on congenital scoliosis (CS), but there is a lack of bibliometric analyses. This study aimed to systematically analyze the developments and focuses in CS and related research fields.

METHODS

Data were retrieved from the Web of Science Core Collection database, and the top 100 most-cited studies were analyzed emphatically. The Web of Science Results Analysis and Citation Report was used to analyze different aspects of the literature. CiteSpace was used to analyze the cooperation network, reference co-citation, burst keywords, and burst citations.

RESULTS

The final analysis included 749 studies. CS and related research has been rapidly expanding. Several journals have published relevant studies and most-cited studies on this topic. Cooperation was noted among authors, institutions, and countries/regions in multiple instances. Surgical techniques (hemivertebra resection/posterior vertebral column resection/vertical expandable prosthetic titanium rib/double approach/grade 4 osteotomy) was one of the most common research focuses. In addition, research on genetics and molecular biology related to CS has become an emerging trend as a result of advances in basic science.

CONCLUSIONS

Over time, research on CS and in related fields has gained greater attention and has been expanding continuously, showing a trend toward globalization. We recommend that researchers focus on the progress of surgical techniques, advances in molecular biology and genetics, and characteristics of CS. The top clusters, most-cited articles, and references with the strongest burst citations should be studied further.

Surgical and Nonsurgical Factors Associated with Salvaging Exposed Vertical Expandable Prosthetic Titanium Rib Hardware

BACKGROUND

Vertical expandable prosthetic titanium rib (VEPTR) devices were designed to treat childhood scoliosis and thoracic insufficiency syndrome. Although they have drastically reduced patient mortality, they present a profound subcutaneous hardware burden. The authors examined the surgical and nonsurgical factors associated with salvage of VEPTR hardware exposures.

METHODS

Between 2014 and 2020, a prospective institutional database was queried for patients with VEPTR hardware complications who required soft-tissue reconstruction. Hardware salvage was considered successful if reconstruction allowed the hardware to be retained until the next VEPTR expansion.

RESULTS

Fifty-eight patients required VEPTR hardware salvage. Hardware complications were successfully salvaged in 62.1 percent of patients at 60.0 percent of operative sites. Neuromuscular scoliosis (p = 0.041) and nonambulatory status (p = 0.018) were factors associated with VEPTR hardware salvage failure, whereas congenital scoliosis was associated with successful hardware salvage (p = 0.012) and preventing need for immediate hardware removal (p = 0.049). Exposed hardware, as compared to threatened exposure, was more likely to require immediate removal (p = 0.045) and result in unsuccessful hardware salvage (p = 0.015).

CONCLUSIONS

Local and regional muscle flaps were able to prevent VEPTR hardware removal in the majority of patients, even in the setting of infection, immobility, incontinence, and multiple systemic comorbidities. Patients with neuromuscular scoliosis and nonambulatory status were at increased risk for failure, whereas those with incontinence and low body mass index trended toward increased risk of failure. Threatened exposure was associated with higher rates of salvage than exposed hardware, and thus earlier referral to plastic surgeons for soft-tissue salvage may be advised.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Risk, III.

Complications in growth-friendly spinal surgeries for early-onset scoliosis: Literature review

BACKGROUND

The treatments for early-onset scoliosis (EOS), defined as curvature of the spine with onset before 10 years of age, continue to pose a great challenge for pediatric orthopedics. The treatment goals for EOS include minimizing spinal deformity while maximizing thoracic volume and pulmonary function. Different surgical techniques have different advantages and drawbacks; however, the two major concerns in the management of EOS are repeated surgeries and complications.

AIM

To review the current literature to assess the safety of EOS surgical treatment in terms of the rate of complications and unplanned surgeries.

METHODS

In January 2021 two independent reviewers systematically searched three electronic medical databases (PubMed, the Cochrane Library, and Embase) for relevant articles. Every step of the review was done according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Due to the heterogeneity of articles and topics after data analysis, a descriptive (synthetic) analysis was performed.

RESULTS

A total of 2136 articles were found. Forty articles were included in this systematic review, after applying our inclusion and exclusion criteria. EOS surgery has a varying but high rate of complications. The most frequent complications were categorized as implant (54%), general (17%), wound (15%) and alignment (12%). The rate of complications might have been even higher than reported, as some authors do not report all types of complications. About 54% of patients required unplanned surgeries due to complications, which comprised 15% of all surgeries.

CONCLUSION

The literature concerning the definitions, collection, and interpretation of data regarding EOS surgery complications is often difficult to interpret. This creates problems in the comparison, analysis, and improvement of spine surgery practice. Additionally, this observation indicates that data on the incidence of complications can be underestimated, and should be interpreted with caution. Awareness of the high rate of complications of EOS surgery is crucial, and an optimal strategy for prevention should become a priority.

[Nonfusion procedures in pediatric scoliosis]

The treatment of early onset scoliosis (EOS) in children is a complex and demanding challenge in the treatment of spinal deformities. Conservative treatment with physiotherapy is indicated in mild forms with a Cobb angle from 10° and additionally a corset treatment with a Cobb angle of more than 20°. After exhaustion of the conservative measures or a progression of spinal scoliosis of 10° or deformities of more than 35°, a surgical approach should be considered in order to prevent respiratory insufficiency as well as severe postural and thoracic deformities. In situations where growth is still ongoing fusion operations can lead to stunted growth, a crankshaft phenomenon or degeneration of alignment. Meaningful alternatives to a fusion are so-called growing rods as a distraction-based nonfusion technique, e.g. traditional growing rods (TGR) and magnetically controlled growing rods (MCGR) or as a further method a vertical expandable prosthetic titanium rib (VEPTR) device. The advantages and disadvantages of each operative procedure must be considered with respect to the risk profile of each patient and the experience of the surgeon in order to guarantee the best possible treatment.

Radiological Outcomes and Complications of Vertical Expandable Titanium Rib Instrumentation in Congenital Scoliosis With or Without Rib Fusion: A Retrospective Study

INTRODUCTION

In congenital anomalies of the thoracic spine, fusion in situ and hemi-epiphysiodesis are unsuitable surgical options, because three-dimensional thoracic deformity and insufficiency are uncorrectable. We aimed to evaluate the radiological outcome of vertical expandable titanium rib (VEPTR) application after follow-up in children with congenital scoliosis with or without rib fusion.

METHODS

In our study, we included 58 patients with congenital scoliosis with or without fused ribs; all treated with VEPTR from 2005 to 2015 at our institute. There were 19 males and 39 females. For each patient, we collected information about age at the index surgery (VEPTR application) and the total number of VEPTR lengthening procedures. Also, Cobb angle, kyphotic angle, thoracic height, and spinal height were measured on preoperative radiographs, immediately post-operative, two years post-operative, and at final follow-up.

RESULTS

The mean duration of follow-up was five years (range, 2-12 years). Twenty-eight patients had rib-to-pelvis type VEPTR, 20 patients had rib-to-rib type VEPTR, and 10 patients had a rib to pedicle/lamina type of VEPTR implant. Post-VEPTR, 63.8% of our patients reported one or more complications. The immediate post-VEPTR application showed that the mean Cobb angle decreased to 43.56° with a percentage change of 22.8% (p<0.001). The mean increase in thoracic height between VEPTR application surgery and final follow-up was 32 mm with a 19.3% increase (p<0.001). Similarly, the mean increase in the spinal height between the VEPTR application surgery and final follow-up was 46.6 mm, with a 23% increase (p<0.001).

CONCLUSIONS

VEPTR instrumentation for congenital scoliosis, with or without rib fusion, successfully corrects the coronal Cobb angle in the majority of patients. It also allows the thoracic (T1-T12) and spinal (T1-S1) growth to approach normal for a particular age.

Is routine intraoperative neuromonitoring necessary in growing rod lengthening procedures? A retrospective, observational study

PURPOSE

To investigate whether intraoperative neuromonitoring (IONM) may be avoided in growing rod lengthening procedures in early onset scoliosis (EOS).

METHODS

A total of 636 primary growing rod surgeries and lengthening procedures were performed in 112 patients with EOS. Traditional growing rods (TGR) or magnetically controlled growing rods (MCGR) were implanted and subsequent lengthening procedures were done at stipulated intervals. Combined multi-modality IONM was used in all index surgeries-but was only used in lengthening procedures in patients with existing spinal cord abnormality or a history of neurosurgical procedure for the same, patients with prior history of a neuromonitoring alert in their index surgery and when lengthening was accompanied by an implant exchange/revision. All the remaining growing rod lengthening procedures were carried out without IONM. Hospital records and operation notes were retrospectively reviewed with focus on details of neurological events/complications.

RESULTS

In 112 primary growing rod applications (TGR = 96, MCGR = 16) and 524 lengthening procedures (TGR = 444, MCGR = 80), intraoperative neuromonitoring 'alerts' were encountered in 6/112 index surgeries and temporary postoperative neurological deficits were seen in 2/112 index surgeries. No intraoperative neuromonitoring event or postoperative neurological complication was encountered in 524 lengthening procedures-irrespective of whether they were carried out along with implant exchange, or in patients with spinal cord abnormality or prior neuromonitoring event during index surgery.

CONCLUSION

While IONM should be used in primary growing rod application surgeries, its use may be avoided in lengthening and implant exchange procedures in a resource-limited setting.

LEVEL OF EVIDENCE

Level 3.

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.

Short fusion with vertebrectomy during growth in congenital spinal deformity: is early surgical intervention recommended?

STUDY DESIGN

This was a multi-center retrospective cohort study included consecutive pediatric patients who were admitted to 8 institutions for the treatment of congenital spinal deformity from 1991 to 2012.

OBJECTIVE

The purpose of this study was to compare curve corrections and balances, reoperations, and complications at 2-year follow-up between those treated early vs. late. Although early intervention has been recommended, no empirical study has examined the optimal timing of short fusion among patients with congenital spinal deformity.

METHODS

Patients with congenital spinal deformity with formation failure undergoing vertebrectomy with short fusion (≤ 6 fusion segments) were categorized as early (surgery at ≤ 6 years) and late (7-18 years) fusion. Outcomes included coronal and sagittal curve corrections at immediate and 2-year evaluations; loss of curve correction from immediate to 2-year follow-up; coronal and sagittal balance at 2 years; and inter-operative, major and minor short-term postoperative, and long-term postoperative complications and reoperations.

RESULTS

Early fusion (N = 79) compared to late fusion (N = 96) was associated with greater percent curve correction at immediate (71% vs. 60%, p = 0.0046) and 2-year (63% vs. 52%, p = 0.0153) evaluations adjusting for surgeon experience and preoperative coronal balance. These associations were significant for males and those with 3-level fusions but not 4 to 6-level fusions. Early fusion compared with late fusion had more intraoperative (6% vs. 1%) and postoperative long-term complications (27% vs. 18%), as well as unplanned reoperations (13% vs. 9%). Early vs. late fusion had fewer short-term complications, both major (6% vs. 15%) and minor (6% vs. 15%).

CONCLUSIONS

Patients who underwent early treatment achieved larger major curve correction by 10% compared to patients with late treatment when assessed at 2-year postoperative evaluation. However, early fusion should be considered with careful attention to possible increased risk of reoperations.

LEVEL OF EVIDENCE

Level III.

Early Results of a Management Algorithm for Collapsing Spine Deformity in Young Children (Below 10-Year Old) With Spinal Muscular Atrophy Type II

BACKGROUND

Progressive C-shaped scoliosis with marked pelvic obliquity is common to spinal muscular atrophy (SMA). Reducing the number of procedures with effective deformity control is critical to minimize the risk of pulmonary complications. This study reports the preliminary results of magnetically controlled growing rods (MCGR) in SMA-related collapsing spine deformity.

METHODS

Inclusion criteria for this retrospective review were: (1) SMA type 2 patients, (2) early onset scoliosis (below 10 y), (3) collapsing spine deformity with pelvic obliquity, (4) growth-friendly scoliosis treatment with MCGR, (5) in between 2014 and 2017. Extracted data included demographic and clinical information, radiologic parameters, surgical details, and final status of the patients.

RESULTS

A total of 11 patients (7 boys, 4 girls) were included. The average age at index surgery was 8.2 (6 to 10) years. Dual MCGR was implanted in 8 patients. In 3 patients, because of curve rigidity and inability of apex to be brought into the stable zone, apical fusion with gliding connectors (convexity) and a single MCGR (concavity) was preferred. Instrumentation included the pelvis in 9 and stopped at the lumbar spine (L3) in 2 patients at the index procedure. Average preoperative deformity of 81.8 degrees (66 to 115) decreased to 29 degrees (11 to 57) postoperatively and was 26 degrees at average 35 months (16 to 59). Pelvic obliquity of 20.9 degrees (11 to 30) decreased to 4.9 degrees (2 to 8) after index surgery and was 6.5 degrees (2 to 16) at the last follow-up. T1-S1 height of 329 mm (280 to 376) after index surgery increased to 356 mm (312 to 390) after 9.2 (4 to 20) outpatient lengthening. No neurologic, infectious, or implant-related complication was recorded. Distal adding-on deformity occurred in 2 patients without initial pelvic fixation.One patient deceased secondary to pneumonia at 16 months after surgery.

CONCLUSIONS

Short-term results indicate that MCGR may be a good option in SMA-associated collapsing spine deformity to reduce the burden of repetitive lengthening procedures. The authors recommend apical deformity control in the convex side in case of curve rigidity. In addition, including the pelvis in the instrumentation at index surgery is critical to prevent distal adding-on.

LEVEL OF EVIDENCE

Level IV-retrospective case series.

Early onset scoliosis and current treatment methods

OBJECTIVE

Provide an update of the management options for early onset scoliosis patients, including general assessment, conservative and surgical options.

METHODS

We included the updated information about the assessment and management options of Early Onset Scoliosis, taking into consideration the non-fusion methods, including the burden on the patient and their family.

RESULTS

With the heterogeneity of this population, it is difficult to get a consensus about a unified protocol for management. Accordingly, the surgeon dealing with these cases needs to be aware of the broad range of surgical and non-surgical methods when treating these patients.

CONCLUSION

The main aim of early onset scoliosis treatment is to gain a flexible spine associated with normal lung development and thoracic growth. Management needs to be individualized between the surgeon and patient in relation to the etiology and patient conditions.

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.

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.

Minimal invasive surgery techniques for patients with adolescent idiopathic and early onset scoliosis

OBJECTIVE

Provide an update on minimal invasive surgery (MIS) techniques for surgical management of pediatric spine.

METHODS

Minimal Invasive surgery for pediatric spine deformity has evolved significantly over the past decade. We include updated information about the surgical management of patients with adolescent idiopathic and Early Onset Scoliosis through MIS techniques. We take into consideration the implementation of this technique in Low-to-Middle Income Countries (LMICs).

RESULTS

Although MIS began as a technique in adult and degenerative spine, recent publications on MIS in pediatric spine cases report benefits of decreased blood loss and infection incidence, and cosmetic advantages from fewer incision numbers. Adoption of MIS techniques in pediatric spine can be facilitated with pre- and intraoperative use of pertinent medical systems.

CONCLUSION

With appropriate considerations and training, MIS is a safe procedure for pediatric spine correction surgery and can be applicable in LMICs.

Incidence of complications in the management of non-ambulatory neuromuscular early-onset scoliosis with a rib-based growing system: high- versus low-tone patients

PURPOSE

The purpose of this study is to evaluate whether patients with high-tone neuromuscular early-onset scoliosis have different surgical outcome and complication rate, when compared to patients with low-tone neuromuscular early-onset scoliosis treated with a rib-to-pelvis rib-based dual growing system.

METHODS

This is a retrospective cohort study of 67 neuromuscular early-onset scoliosis patients, collected from a multicenter database, treated with a rib-to-pelvis rib-based dual growing system. All patients were divided into two groups: high tone and low tone. Pre-, intra- and postoperative data were compared between both groups. Complications were reported by a standardized system.

RESULTS

Twenty-six high-tone and 41 low-tone patients were found homogeneous regarding gender, age at surgery, weight, height, estimated blood loss and surgery time. High-tone group (19/26 = 73.1%) experiences more postoperative complications than low-tone group (22/41 = 53.7%). Most common complications were infection, device migration, death and hardware failure. Permanent abandonment of rib-based growing technique and device removal was required in 21% of high-tone patients (P < 0.001). None of the low-tone patients required abandonment.

CONCLUSION

High-tone patients had more complications than those with low tone in management of neuromuscular early-onset scoliosis treated with a rib-to-pelvis rib-based dual growing system. A different surgical approach may be required to treat the high-tone neuromuscular early-onset scoliosis.

Non-Fusion Surgical Correction of Thoracic Idiopathic Scoliosis Using a Novel, Braided Vertebral Body Tethering Device: Minimum Follow-up of 4 Years

Anterior vertebral body tethering to effect scoliosis correction in a growing spine has been shown to work with varying degrees of success. This report describes the mid-term results of this technique using a new device composed of a braided ultra-high molecular weight polyethylene (UHMWPE) cord anchored to bone screws applied without segmental compression.

Methods

This was a single-center prospective observational study of an investigational device. Five female patients aged 9 to 12 years with thoracic scoliosis underwent thoracoscopic insertion of the UHMWPE tether. Radiographs and magnetic resonance imaging (MRI) were performed, and the Scoliosis Research Society (SRS)-22 was administered, preoperatively and at regular intervals after surgery, with a minimum of 4 years of follow-up.

Results

All tethering devices spanning the end vertebrae (range, 7 to 8 vertebrae) were implanted successfully. Mean blood loss was 136 mL, and the mean operative time was 205 minutes. The mean preoperative main thoracic Cobb angle was 40.1°. Curve correction of the tethered segment ranged from 0% to 133.3% at 4 years. We observed greater correction in 2 patients with open triradiate cartilage (TRC), achieving full scoliosis correction at 2 years and 121.5% at 4 years. MRI showed improvement in periapical disc wedging morphology and 55% improvement of rotation at 3 years. There were 20 adverse events, of which 16 were mild and 4 were moderate in severity. The 4 moderate events of pneumonia, distal decompensation, curve progression, and overcorrection occurred in 3 patients, 2 of whom required fusion.

Conclusions

Anterior vertebral body tethering resulted in scoliosis deformity correction in the coronal and axial planes, with preservation of curve flexibility. Actual correction by growth modulation was noted only in patients with open TRC, whereas curve stabilization was noted in patients with closed TRC. Overcorrection, curve progression, and distal decompensation are problems with this technique.

Level of Evidence

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

Site-specific Surgical Site Infection Rates for Rib-based Distraction

BACKGROUND

Implantable rib-based distraction devices have revolutionized the treatment of children with early onset scoliosis and thoracic insufficiency syndrome. Unfortunately, the need for multiple skin incisions and repeated surgeries in a fragile patient population creates considerable infection risk. In order to assess rates of infection for different incision locations and potential risk factors, we generated a prospectively collected database of patients treated with rib-based distraction devices.

METHODS

We analyzed a cohort of patients with thoracic insufficiency syndrome from various etiologies that our institution treated with rib-based distraction devices from 2013 to 2016. Surgery type (implantation, expansion, revision/removal), and surgeon adjudicated surgical site infection (SSI) were collected. For this study, we developed a novel, rib-based distraction device surgical site labeling system in which incisions could be labeled as either proximal or distal surgical exposure areas. Treating surgeons documented the operative site, procedure, and SSI site in real-time.

RESULTS

A total of 166 unique patients underwent 670 procedures during the study period, producing 1537 evaluable surgical sites; 1299 proximal and 238 distal. Patients were 6.81±4.0 years of age on average. Forty-seven procedures documented SSIs (7.0%), while 40 (24.1%) patients experienced an infection. Analysis showed significant variation in the rate of infection between implantation, and expansion, and revision procedures, with implantation procedures having the highest infection rate at 13.1% (P<0.01). Infections occurred more frequently at distal sites than proximal ones (P=0.02).

CONCLUSIONS

Our novel, surgeon-entered, prospective quality improvement database has identified distal surgical sites as being at higher risk for SSI than proximal ones. Further, rib-based distraction device implantation procedures were identified as being at a greater risk for SSI than expansion or revision procedures. We believe this data can lead to improved prevention measures, anticipatory guidance, and patient care.

LEVEL OF EVIDENCE

Level II-prognostic study.

The Effect of Expansion Thoracostomy on Spine Growth in Patients with Spinal Deformity and Fused Ribs Treated with Rib-Based Growing Constructs

STUDY DESIGN

Retrospective review of prospective registries.

OBJECTIVES

We hypothesized that patients with congenitally fused ribs who underwent thoracostomy upon implantation of rib-based distraction devices would achieve improved spine growth compared with those who did not undergo thoracostomy.

SUMMARY OF BACKGROUND DATA

Patients with fused ribs may develop thoracic insufficiency syndrome. Treatment for severe early-onset spinal deformity with rib fusions often includes the placement of rib-based expansion devices with surgical division of the fused ribs (thoracostomy). The effect of thoracostomy on spinal growth has not been fully examined.

METHODS

Two multicenter registries of primarily prospectively collected data were searched. Patients with fused ribs and implantation of a rib-based device were identified. A total of 151 patients with rib fusions treated with rib-based constructs and minimum two-year follow-up were included. Among those, 103 patients were treated with expansion thoracostomy at the time of implantation, whereas 48 patients received device implantation alone. We evaluated change in T1-T12 and T1-S1 height, coronal Cobb angle, kyphosis, and number of surgeries. Preoperative deformity was similar between the two groups. Only 19% of patient underwent final fusion, with similar numbers fused in each group.

RESULTS

At latest follow-up, the expansion thoracostomy group had a greater total improvement in T1-S1 height (7.2 cm vs. 4.8 cm, p = .004). There was no difference between the two groups for change in spinal height at each lengthening procedure. Interestingly, thoracostomy patients also underwent more total surgeries (11.5 vs. 9.6, p = .031) and more lengthening procedures (8.3 vs. 6.6, p = .017) than the comparison group despite similar length of follow-up.

CONCLUSIONS

Patients who underwent expansion thoracostomy at the time of rib expansion device implantation achieved greater improvement in T1-S1 height than those who underwent implantation of rib expansion device alone. Further work is needed to evaluate whether expansion thoracostomy impacts pulmonary function.

Biomechanical Analysis of a Growing Rod with Sliding Pedicle Screw System for Early-Onset Scoliosis

Early-onset scoliosis (EOS) remains a challenging condition for which current nonfusion surgeries require iterative lengthening surgeries. A growing rod with sliding pedicle screw system (GRSPSS) was developed to treat spinal deformities without repeated operative lengthening. This study was performed to evaluate whether GRSPSS had similar stability as a conventional pedicle screw system to maintain deformity correction. A serial-linkage robotic manipulator with a six-axis load cell positioned on the end-effector was utilized to evaluate the mechanical stability of the GRSPSS versus conventional fixed scoliosis instrumentation. Ten skeletally mature thoracic female Katahdin sheep spines (T4-L1) were subjected to 2.5 Nm of flexion-extension (FE), lateral bending (LB), and axial rotation (AR) in 2° increments for each state. The overall range of motion (ROM), apical segment ROM, and stiffness were calculated and reported. A two-tailed paired t-test was used to detect significant differences (p < 0.05) between the fixed group and GRSPSS fixation. There were no significant differences in overall range of motion (ROM), apical segment ROM, or stiffness for FE or LB between the GRSPSS group and fixed group. In AR, the GRSPSS group showed increased ROM compared to the fixed group for the overall spine (36.0° versus 19.2°, p < 0.01) and for the instrumented T8-T10 segments (7.0° versus 2.9°, p=0.02). Similarly, the fixed rod elastic zone (EZ) stiffness was significantly greater than the GRSPSS EZ stiffness (0.29 N/m versus 0.17 N/m, p < 0.001). The space around the rod allows for the increased AR observed with the GRSPSS fusion technique and is necessary for axial growth. The GRSPSS fusion model shows equivalent flexion and LB stability to current fusion models and represents a stable fusion technique and may allow for longitudinal growth during childhood.

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.

Novel use of telescoping growth rods in treatment of early onset scoliosis: An in vivo and in vitro study in a porcine model

INTRODUCTION

Treatment of early-onset scoliosis (EOS) can be difficult. Various forms of growing rods exist to correct deformity while delaying definitive spinal fusion. The disadvantage of traditional growing rods is need for repeated surgical lengthening procedures. Telescoping growth rods (TelGR) are a prototype new, guided growth technology with a rod mechanism that allows spontaneous longitudinal growth over time without manual lengthening. We hypothesized that the TelGR system will permit unrestricted growth with limited complications through 12 weeks in vivo, and that the range of motion (RoM) in each of three directions and stiffness of the TelGR system would not be significantly different than the rigid rod system in vitro.

MATERIALS AND METHODS

In vivo: Six immature pigs were surgically implanted with TelGR with cephalad fixation at T6-7 and caudal fixation at T14-L1. Radiographs of the involved vertebral segments were measured postoperatively and after 12 weeks. In vitro: A robotic testing system was utilized for flexibility tests in flexion-extension (FE), lateral bending (LB), and axial rotation (AR) of eight immature porcine specimens (T3-T15). Testing was performed on both dual rigid rods and bilateral TelGR with instrumentation at T4-5 and T13-14.

RESULTS

In vivo: Over the 12-week period, the rod length of the TelGR increased an average of 65 mm. In vitro: TelGR demonstrated significantly increased motion in LB and AR RoM compared with rigid rods. No difference was noted in FE RoM.

DISCUSSION

The in vivo results in this study showed expected skeletal growth with spines instrumented with TelGR. In vitro findings of increased RoM in AR and LB suggest that the TelGR system may be less rigid than traditional growing rods. Treatment with TelGR might, if proven efficacious in the clinical setting, decrease the need for repeated surgical intervention compared with traditional growing rods. This study adds to the limited body of biomechanical evidence examining guided growth technology.

EVALUATION OF THE VEPTR SYSTEM IN THE MANAGEMENT OF SPINAL DEFORMITIES BETWEEN 2008 AND 2014 AT THE ROOSEVELT INSTITUTE

ABSTRACT Objective: Traditional surgical treatments, such as on-site fusion and hemiepiphysiodesis, have not addressed chest deformity in its three dimensions, and are usually insufficient and unpredictable for the management of congenital and neuromuscular scoliosis. The application of the Vertical Expandable Prosthetic Titanium Rib (VEPTR) is a technique developed to treat early-onset progressive scoliosis that elongates the spine and thoracic wall, allowing adequate lung development. Methods: A case series retrospective study was conducted. We included 23 patients, including fifteen females and eight males diagnosed with congenital and neuromuscular scoliosis, who were treated with VEPTR type implants between January 2008 and May 2014. We obtained data about the implant and pre and postoperative radiographic images to assess the magnitude of the curve, and we measured the Cobb angle and length after lengthening, as well as evaluating the complications found. Results: There was an improvement in the postoperative Cobb angle. In patients with congenital scoliosis, deformity correction was 8.6% (p=0.014), and in neuromuscular scoliosis, we observed deformity correction of 19.5% (p=0.009). Likewise, we found gains in thoracic height through the device, which results in an average 10% lengthening of the spine in congenital scoliosis. In this study, we identified complications such as material migrations, rib synostosis, pressure zones, rib fracture, hemothorax, and deep wound infection. Conclusion: The natural history of progressive spinal deformity was improved in most of the minors, through the use of VEPTR. This allows us to continue managing patients in the future, in order to make a deeper assessment of its performance in treatment of early onset scoliosis. Level of Evidence III; Therapeutic studies - Investigating the results of a treatment.

Parallel Proximal Fixation in Rib-Based Growing Rod System: A Novel Approach to Deal With Proximal Anchor Migration

STUDY DESIGN

Retrospective case control.

OBJECTIVE

To report on differences in implant failure rates and complications requiring reoperation in children with early-onset scoliosis (EOS) treated with rib-based distraction utilizing four proximal fixation points in either a parallel or in-line configuration.

SUMMARY OF BACKGROUND DATA

Proximal anchor failure continues to be a significant problem in growth-friendly surgery using rib-based distraction to treat children with EOS. Differences between parallel and in-line proximal anchor constructs have not been previously assessed.

METHODS

A multicenter registry was reviewed to identify children treated for EOS with rib-based distraction between 2011 and 2014 with a minimum of 2 years follow-up after implantation. Patients were divided into those with in-line and parallel proximal rib-cradle configurations, and only those with exactly four fixation points (two per side) were included. Charts were reviewed for demographic, clinical, and radiographic information.

RESULTS

A total of 56 patients were identified-31 with in-line constructs and 25 with parallel constructs. Follow-up in the in-line group was a mean of 4.06 years versus 3.16 in the parallel group (P = 0.001). Controlling for the different lengths of follow-up in the two groups there was a significantly higher rate of implant failure (P = 0.043) and requirement for nonroutine surgical intervention (P = 0.029) in the in-line group. There was a trend toward increased complications in the in-line group (P = 0.058).

CONCLUSION

Failure of proximal fixation is the most common complication in management of EOS with rib-based distraction. This study identifies that when the number of proximal fixation points are matched, parallel constructs result in lower rates of implant failure and need for unplanned reoperation than in-line constructs. Although this study was limited to patients in whom the VEPTR device was employed, these principles are likely applicable to other rib-based distraction devices used to treat EOS.

LEVEL OF EVIDENCE

3.

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.

Comparison of Percentile Weight Gain of Growth-Friendly Constructs in Early-Onset Scoliosis

STUDY DESIGN

Multicenter retrospective cohort.

OBJECTIVE

To compare improvement in nutritional status seen in early-onset scoliosis (EOS) patients following treatment with various growth-friendly techniques, especially in underweight patients (<20th weight percentile).

BACKGROUND

Thoracic insufficiency resulting from EOS can lead to severe cardiopulmonary disease. In this age group, pulmonary function tests are often difficult or impossible to perform. Weight gain has been used in prior studies as a proxy for improvement and has been demonstrated following VEPTR and growing rod implantation. In this study, we aim to analyze weight gain of EOS patients treated with four different spinal implants to evaluate if significant differences in weight percentile change exist between them.

METHODS

Retrospective review of patients treated surgically for EOS was performed from a multicenter database. Exclusion criteria were index instrumentation at >10 years old and <2 years' follow-up.

RESULTS

287 patients met the inclusion criteria and etiologies were as follows: congenital = 85; syndromic = 79; neuromuscular = 69; and idiopathic = 52. Average patient age at surgery was 5.41 years, with an average follow-up of 5.8 years. Preoperatively, 55.4% (162/287) fell below the 20th weight percentile. There was no significant difference in preoperative weight between implants (p = .77), or diagnoses (p = .25). Among this group, the mean change in weight percentile was 10.5% (range: -16.7% to 88.7%) and all implant groups increased in mean weight percentile at final follow-up. There were no significant differences in weight percentile change between the groups when divided by implant type (p = .17).

CONCLUSIONS

Treatment of EOS with growth-friendly constructs resulted in an increase in weight percentile for underweight patients (<20th percentile), with no significant difference between constructs.

LEVEL OF EVIDENCE

Level III.

Performing a Definitive Fusion in Juvenile CP Patients is a Good Surgical Option

BACKGROUND

In juveniles with progressive curves, there is debate regarding the use of growth friendly implants versus definitive fusion. This study presents outcomes of juvenile cerebral palsy (CP) scoliosis patients who underwent definitive fusion before age 11.

METHODS

A review of a prospective, multicenter registry identified patients 10 years and younger who had a definitive posterior fusion for their CP scoliosis. Preoperative and postoperative demographic and radiographic changes were evaluated with descriptive statistics. Repeated measures analysis of variance were utilized to compare outcome scores.

RESULTS

Fourteen children with a mean age of 9.7 years (8.3 to 10.8 y) and a minimum of 2 years follow-up (range 2 to 3 y) were identified. The mean preoperative curve magnitude and pelvic obliquity was 84±25 degrees (range 63 to 144 degrees) and 25±14 degrees, respectively. All patients were skeletally immature with open triradiate cartilage. Three patients had unit rods with wires while the rest incorporated pedicle screws. Immediately postoperation, the average major curve was 25±17 degrees (P≤0.001, 71% correction rate). At most recent follow-up, the average major curve increased to 30±18 degrees (P≤0.001) for a 65% correction rate. Pelvic obliquity improved to 4±4 degrees (84% correction, P≤0.001) immediately postoperation and to 6±5 degrees (P=0.002) at latest follow-up for a 76% correction rate. None of the patients required revision surgery for progression. From pre to most recent follow-up, the CPchild Health outcome scores improved from 47 to 58 (P=0.019). One patient had a deep infection, and 1 patient had a broken rod that did not require any further treatment.

CONCLUSIONS

Progressive scoliosis in juvenile CP patients requires the surgeon to balance the need for further growth with the risks of progression or repeated surgical procedures. Our study demonstrates that definitive fusion once the curves approach 90 degrees results in significant radiographic and quality of life improvements, but further follow-up is needed to determine whether those results remain after skeletal maturity.

LEVEL OF EVIDENCE

Level IV-therapeutic.

Patients Without Intraoperative Neuromonitoring (IONM) Alerts During VEPTR Implantation Did Not Sustain Neurological Injury During Subsequent Routine Expansions: A Retrospective Multicenter Cohort Study

BACKGROUND

The purpose of this study was to determine the rate of intraoperative neurological monitoring (IONM) alerts and neurological injury during vertical expandable prosthetic titanium rib (VEPTR) treatment and evaluate the utility of IONM during VEPTR expansion procedures in patients who have not previously had neurological injury or IONM alerts.

METHODS

After institutional review board approval, VEPTR procedures and IONM records were reviewed at 17 institutions for patients treated with VEPTR from 2005 to 2011. All consecutive cases in patients with minimum 2-year follow-up were included. Patients with prior history of growing rods or other invasive spine-based surgical treatment were excluded. Surgeries were categorized into implant, revision, expansion, and removal procedures. Cases with IONM alerts or neurological injury had additional detailed review. Descriptive statistics were used for data analysis.

RESULTS

In total, 2355 consecutive VEPTR procedures (352 patients) consisting of 299 implant, 377 revision, 1587 expansion, and 92 removal procedures were included. In total, 620 VEPTR procedures had IONM, and 539 of those had IONM records available for review. IONM alerts occurred in 9/539 procedures (1.7%): 3/192 implants (1.6%), 3/58 revisions (5.2%), and 3/258 expansions (1.2%). New neurological injury occurred in 3/2355 procedures (0.1%), 3/352 patients (0.9%). All 3 injuries were in implant procedures, only 1 had an IONM alert. All 3 had upper extremity motor deficits (1 had sensory deficit also). All had full recovery at 17, 30, and 124 days postinjury. One patient without prior neurological injury or IONM alert had an IONM alert during expansion that resolved after an increase in blood pressure. The remaining IONM alerts during expansions were all in children with prior IONM alerts during implant, revision, or exchange procedures.

CONCLUSIONS

The highest rate of neurological injury in VEPTR surgery was found for implant procedures. There were no instances of neurological injury during VEPTR expansion, revision, or removal procedures. IONM did not identify new neurological injuries in patients undergoing VEPTR expansion who did not previously have a history of IONM signal change or neurologic injury.

LEVEL OF EVIDENCE

Level IV-diagnostic study.

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.

Management and outcomes of scoliosis in children with congenital diaphragmatic hernia

PURPOSE

The purpose of this study was to evaluate the management and outcomes of CDH patients with scoliosis.

METHODS

From January 1996 to August 2015, 26 of 380 (7%) CDH patients were diagnosed with scoliosis. Six (23%) were prenatally diagnosed by ultrasound, and 9 (35%) were diagnosed postnatally. The remaining 11 (42%) developed scoliosis after discharge. Mean follow-up was 6.6years.

RESULTS

Among the 15 patients with congenital scoliosis, there were 2 (13%) perinatal deaths. Five of the 13 (38%) survivors required orthopedic surgery, and 2 have required bracing. The mean age at initial surgery was 7years. These five children underwent an average of 2.8 (range 1-7) expansions or revisions. All surgical patients required supplemental oxygen at 28days of life, and 1 required a tracheostomy. None of the 11 patients who developed scoliosis later in life required surgery, but 3 have required bracing. Six of the 11 (55%) required a patch repair for CDH compared to 158 of 264 (60%) CDH patients without scoliosis (p=0.73).

CONCLUSIONS

Early diagnosis of scoliosis in CDH patients is associated with a high rate of surgery. There was not a higher incidence of patch repair among patients who developed scoliosis.

LEVEL OF EVIDENCE

Prognosis. Retrospective study, level II.

VEPTR Implantation After Age 3 is Associated With Similar Radiographic Outcomes With Fewer Complications

BACKGROUND

The purpose of this study was to analyze the risks and benefits of early vertical expandable prosthetic titanium rib (VEPTR) implantation (below 3 y of age) compared with delayed intervention (3 to 6 y of age). Early intervention with milder deformity may make device implantation easier and may facilitate symmetric chest and pulmonary development. However, later intervention may decrease the number of lengthenings required, and implant anchor points and bone quality may be better in older patients.

METHODS

A multicenter prospective database of patients treated with the VEPTR device was retrospectively reviewed. A total of 71 patients with minimum 5-year follow-up were included. Thirty-seven patients had VEPTR surgery below 3 years of age (group 1), and 34 patients had surgery between 3 and 6 years of age (group 2). Radiographs from the preoperative, immediate postoperative, and most recent follow-up visits were reviewed to determine coronal plane deformity and change in T1-T12 height over time. Complications were analyzed using a nonparametric mean cumulative function for the number of complications per subject over time.

RESULTS

Patients in both groups had similar diagnoses, ASA scores (P=0.22), and number of lengthenings (10±4 in both groups, P=0.40). Preoperative and most recent major Cobb angles were not significantly different between the 2 groups [66±22 and 60±20 degrees (group 1) vs. 63±19 and 57±23 degrees (group 2), respectively] (P=0.38). The change in T1-T12 was significantly correlated with the number of lengthenings (P<0.001); however, there was no difference between age groups (P=0.55). There were 118 complications in 33 subjects in group 1 and there were 69 complications in 28 subjects in group 2. The number of complications per lengthening was significantly different between the 2 age groups (P<0.001). Subjects in group 2 had 41% fewer complications per lengthening compared with subjects in group 1 (P<0.001).

CONCLUSIONS

VEPTR treatment resulted in similar deformity control and thoracic growth in both age groups with lower complication rates in the older population. The rate of complications was similar between the 2 groups for the first 2 years postimplantation, but after 2 years, the rate of complications increased over time faster for the younger group compared with the older group.

LEVEL OF EVIDENCE

Level III-retrospective chart and radiographic review.

Growing rod erosion through the lamina causing spinal cord compression in an 8-year-old girl with early-onset scoliosis

BACKGROUND CONTEXT

Early-onset scoliosis often occurs by the age of 5 years and is attributed to many structural abnormalities. Syndromic early-onset scoliosis is considered one of the most aggressive types of early-onset scoliosis. Treatment starts with serial casting and bracing, but eventually most of these patients undergo growth-sparing procedures, such as a single growing rod, dual growing rods, or a vertical expandable titanium prosthetic rib.

PURPOSE

This case report aimed to describe an unusual complication of erosion of a growing rod through the lamina that caused spinal cord compression in an 8-year-old girl with early-onset scoliosis.

STUDY DESIGN

This is a case report.

METHODS

A retrospective chart review was used to describe the clinical course and radiographic findings of this case after rod erosion into the spinal canal.

RESULTS

The patient underwent successful revision surgery removing the rod without neurologic complications.

CONCLUSIONS

Patients with syndromic early-onset scoliosis are more prone to progressive curves and severe rotational deformity. We believe that the severe kyphotic deformity in addition to the dysplastic nature of the deformity in this population may predispose them to this unusual complication.

Use of Vertical Expandable Prosthetic Titanium Rib (VEPTR) in the Treatment of Congenital Scoliosis Without Fused Ribs

BACKGROUND

Although the vertical expandable prosthetic titanium rib (VEPTR) has been shown to be useful in treating congenital scoliosis (CS) with fused ribs, no studies to date have specifically evaluated the efficacy of VEPTR in the treatment of CS without fused ribs. The purpose of this study was to determine the effectiveness of VEPTR in sagittal/coronal curve correction and spine growth and compare its complication rate to the use of VEPTR in other conditions and to other treatment methods used for CS.

METHODS

A multicenter database was queried for patients with CS without fused ribs treated with VEPTR. Anteroposterior (AP) and lateral radiographs were used to measure parameters at 3 timepoints (preoperative, immediate postoperative, and latest follow-up): coronal Cobb angle, sagittal kyphosis, and thoracic and lumbar spine heights. Clinical data included age, time to follow-up, and complications.

RESULTS

Twenty-five patients (13 females, 12 males) were identified. The average age at implantation was 5.7 years, with an average follow-up of 50 months. Several parameters improved from preoperative to latest follow-up: coronal Cobb angle (69 to 54 degrees, P<0.0001), thoracic spine height (T1-T12) in the AP (13.3 to 15.9 cm, P<0.0001) and lateral (14.8 to 17.4 cm, P=0.0024) planes, and lumbar spine height (L1-S1) in the AP (8.8 to 11.4 cm, P<0.0001) and lateral (9.9 to 11.9 cm, P=0.0002) planes. Kyphosis increased over the study period (36 to 41 degrees, P=0.6). Fifteen patients (60%) had 41 complications (average 2.75; range, 1 to 12). Twenty-eight complications (68%) were device-related, and 13 (32%) were disease-related. The most common complications were infection, wound dehiscence, and device migration. Six complications (15%) altered the course of treatment. Thoracic spine height increased 79% of expected growth.

CONCLUSION

VEPTR is an effective treatment for patients with CS without fused ribs, as evidenced by improved radiographic parameters and increased spinal height, with a complication rate which is high but similar to other methods of treatment.

LEVEL OF EVIDENCE

Level IV-case series.

Bilateral Rib-Based Distraction to the Pelvis for the Management of Congenital Gibbus Deformity in the Growing Child With Myelodysplasia

BACKGROUND

Congenital gibbus deformity of the spine associated with myelodysplasia is a challenging problem in the growing child and is commonly associated with skin breakdown and chronic infection. Surgical solutions including kyphectomy, flap closure of the skin, and early spinal fusion are associated with a high rate of complications and, ultimately, a short trunk due to stoppage of spinal growth. The purpose of this article is to describe our early results in using a rib-based distraction to the pelvis without vertebral resection and fusion to manage this deformity.

METHODS

This is an IRB-approved retrospective study of a consecutive single-surgeon series of using the rib-to-pelvis distraction technique in congenital gibbus deformity. There were four patients (two males, two females) with an average age of 20 months (16-25 months). The diagnosis was myelomeningocele (n = 2), congenital kyphosis (n = 1), and congenital kyphoscoliosis (n = 1). All patients were managed with bilateral rib-to-pelvis distraction using the Vertical Expandable Prosthetic Titanium Rib (VEPTR) device.

RESULTS

The average preoperative gibbus deformity measured 114 degrees (range = 108-154). The average postoperative gibbus measured 52 degrees (range = 36-80). The average length of postoperative follow-up is 66 months (range = 48-84 months). There were 10 complications; a dural leak during device expansion, rib hook migrations and postoperative infections after initial implant that resolved with irrigation, debridement, and intravenous antibiotics. One patient had skin expanders placed preoperatively to facilitate skin coverage. No patient has required vertebral resection to achieve correction of the deformity. No patient has had subsequent skin breakdown over the residual gibbus.

DISCUSSION

This minimally invasive technique effectively corrects gibbus deformity in the growing child without early vertebral column resection and fusion. Our practice is to intervene early while the gibbus is flexible and prior to skin breakdown over the deformity. These early results are encouraging, but further long-term follow-up is needed to confirm the benefits of this technique over traditional methods.

LEVEL OF EVIDENCE

IV.

The effect of vertical expandable prosthetic titanium rib on growth in congenital scoliosis

Aims:

In the treatment of thoracic insufficiency syndrome, the main aim is to maintain spinal and thoracic growth in order to continue respiratory functions. Vertical expandable prosthetic titanium rib (VEPTR) device application is a method of choice especially in the congenital cases with a thoracic deformity. In our study, we evaluated the effect of VEPTR on growth in congenital scoliosis.

Materials and Methods:

Four female patients in whom VEPTR was applied were retrospectively evaluated. Anteroposterior (AP) and lateral Cobb angles that were measured preoperatively and during the last control, space available for lung (SAL), T1-S1 and T1-T12 distances, coronal and sagittal balances were compared.

Results:

Four female patients in whom VEPTR was applied were retrospectively evaluated. AP and lateral Cobb angles that were measured preoperatively and during the last control, SAL, T1-S1, and T1-T12 distances, coronal and sagittal balances were compared.

Conclusions:

VEPTR may provide a good correction, and we observed a growth in the spine height and SAL following the treatment of congenital deformities. Long-term, multicenter, prospective studies that compare the spinal height, respiratory functions, the severity of the deformity, and the spinal balance are required in order to evaluate the efficacy of VEPTR.

Orthopedic Management of Scoliosis by Garches Brace and Spinal Fusion in SMA Type 2 Children

BACKGROUND

Scoliosis is the most debilitating issue in SMA type 2 patients. No evidence confirms the efficacy of Garches braces (GB) to delay definitive spinal fusion.

OBJECTIVE

Compare orthopedic and pulmonary outcomes in children with SMA type 2 function to management.

METHOD

We carried out a monocentric retrospective study on 29 SMA type 2 children who had spinal fusion between 1999 and 2009. Patients were divided in 3 groups: group 1-French patients (12 children) with a preventive use of GB; group 2-French patients (10 children) with use of GB after the beginning of the scoliosis curve; and group 3-Italian patients (7 children) with use of GB after the beginning of the scoliosis curve referred to our centre to perform orthopedic preoperative management.

RESULTS

Mean preoperative and postoperative Cobb angle were significantly lower in the group 1 of proactively braced than in group 2 or 3 (Anova p = 0.03; Kruskal Wallis test p = 0.05). Better surgical results were observed in patients with a minor preoperative Cobb angle (r = 0.92 p <  0.0001). Fewer patients in the group 1 proactively braced required trunk casts and/or halo traction and an additional anterior fusion in comparison with patients in the group 2 and 3. Moreover, major complications tend to be less in the group 1 proactively braced. No significant differences were found between groups in pulmonary outcome measures.

CONCLUSIONS

A proactive orthotic management may improve orthopedic outcome in SMA type 2. Further prospective studies comparing SMA management are needed to confirm these results.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions to Authors on jbjs.org for a complete description of levels of evidence (Retrospective comparative study).

Shilla Growth Guidance for Early-Onset Scoliosis: Results After a Minimum of Five Years of Follow-up

BACKGROUND

The Shilla growth guidance technique was developed to allow growth during treatment of a child's spinal deformity without requiring repeated surgery for lengthening procedures. Dual stainless-steel rods are fixed posteriorly to the corrected apex via pedicle screws with a limited fusion at the apex and are combined with sliding pedicle screws to allow vertebral growth in a cephalad and caudad direction.

METHODS

A retrospective study of the original forty patients treated with the Shilla method for a severe deformity of a growing spine was performed to determine the efficacy of the procedure.

RESULTS

The etiology of the spinal deformity in the forty patients was idiopathic in nine, congenital in one, neuromuscular in sixteen, and syndromic in fourteen. The average age at the index surgery was six years and eleven months, and the average duration of follow-up for the thirty-three eligible patients was seven years (range, four years and nine months to ten years and nine months). The curves averaged 69° (range, 40° to 115°) preoperatively and 38.4° (range, 16° to 74°) at the time of the most recent follow-up or prior to definitive spinal instrumentation and fusion. Complications included secondary infections (six patients), alignment issues (eight patients), and implant-related problems (twenty-four patients), with some patients experiencing more than one complication.

CONCLUSIONS

The Shilla growth guidance technique is a method of scoliosis treatment that allows spinal growth while controlling the deformity without scheduled repeated surgical procedures. The complication rate is high (73%) but acceptable, and children with a wide variety of diagnoses can be safely treated with the Shilla procedure.

Parasol Rib Deformity in Hypotonic Neuromuscular Scoliosis: A New Radiographical Definition and a Comparison of Short-term Treatment Outcomes With VEPTR and Growing Rods

STUDY DESIGN

Retrospective review of 2 multicenter national databases, Growing Spine Study Group and Chest Wall and Spine Deformity.

OBJECTIVE

To derive an objective measure of parasol rib deformity from spine radiographs and to compare efficacy of rib-based (vertical expandable prosthetic titanium rib (VEPTR)) versus spine-based growing rods ("GR") instrumentation to improve parasol rib deformity and pulmonary function.

SUMMARY OF BACKGROUND DATA

Children with low tone neuromuscular scoliosis often develop collapse of the rib cage ("parasol rib deformity") that may be associated with poor pulmonary function.

METHODS

We compared patients with hypotonic neuromuscular scoliosis treated by VEPTR or GR with greater than 1 year follow-up. Preoperative and final spine radiographs were assessed for parasol rib collapse, spine asymmetry, and thoracic deformity. Multivariable analysis was performed on these measurements to identify the best descriptor of parasol rib deformity. Using this measurement, the ability of VEPTR versus GR to control parasol rib deformity was then compared. Assisted ventilation rating (AVR) at preoperative and final follow-up was compared between the 2 groups.

RESULTS

Twenty-three patients treated with VEPTR (average age 6.7 years, average f/u = 3.3 years) were compared with 22 patients treated with GR (average age 7.7 years, average f/u = 2.9 years). The equation Parasol Score = (T6 convex hemithoracic width/T6 concave hemithoracic width) × (T6 thoracic width/T12 thoracic width) was the most accurate descriptor rib collapse (AUC = 0.927). Parasol Score was correlated with AVR. Parasol Score did not change over time for the patients treated with GR, but had a tendency to worsen for patients treated with VEPTR. AVR did not change significantly in either group. Spine deformity was better corrected using GR.

CONCLUSION

Parasol rib deformity, measured on x-ray by the metric = (T6 width convex hemithorax/T6 width concave hemithorax)*(T6 thoracic width/T12 thoracic width), did not improve after treatment with VEPTR or GR. AVR did not change significantly in either group.

LEVEL OF EVIDENCE

4.

Bacterial colonization of VEPTR implants under repeated expansions in children with severe early onset spinal deformities

PURPOSE

Historically, severe spinal and thoracic deformities in children were treated with early long spinal fusions. This prevented further growth of the spine and thorax and often led to small stiff thoraces. Therefore, growth-retaining implants, like vertical expandable titanium ribs (VEPTR), were developed to stimulate thoracic and spinal growth. To accommodate growth, these implants have to be expanded every 6 months. Infection rates of up to 2 % per procedure are reported. Exchange of implant parts allows analyzing the development of implant-related infections and subclinical colonizations.

METHODS

In this prospective study, all patients undergoing repeat VEPTR expansion procedures at our institution were included. Preoperatively, clinical signs of infection were documented, and blood samples were taken. The removed implants were treated by sonication and microbiologically analyzed. The clinical follow-up was documented.

RESULTS

From January 2009 to May 2012, 39 children with 163 re-operations were included. Four of the 39 patients (10 %) developed clinical apparent infections and had implant removal. These were excluded and analyzed separately. Of 144 procedures, implant parts were eligible for analysis. Implant colonization was detected by sonication in 24 of 144 (16 %) operations in 18 out of 39 (46 %) patients. Repeated detection occurred in 5 (14 %) patients. No risk factors for colonization could be identified.

CONCLUSION

The rate of implant colonization is 4.5 times higher than the rate of manifest infections in VEPTR patients. Colonization may lead to a manifest infection over time. The knowledge of persistent implant colonization may change the treatment algorithm in patients with growth-retaining implants.

Use of Rib-Based Distraction in the Treatment of Early-Onset Scoliosis Associated With Neurofibromatosis Type 1 in the Young Child

STUDY DESIGN

This study was an institutional review board-approved retrospective review of a prospectively collected multicenter database for rib-based distraction systems used in the treatment of young children with early-onset scoliosis associated with neurofibromatosis type 1 (NF-1).

OBJECTIVE

To evaluate the effectiveness of rib-based distraction and associated complications in managing scoliosis in the growing child with NF-1.

SUMMARY OF BACKGROUND DATA

Patients with NF-1 commonly have scoliosis with curves that can be dysplastic and progressive and respond poorly to bracing. Rib-based distraction systems have recently been described in the management of these complex patients. The efficacy and complication rate using these systems have not previously been reported.

METHODS

Twelve children with NF-1 and scoliosis who were treated with rib-based distraction systems were identified from a prospectively collected multicenter registry. Preoperative and postoperative Cobb angle and T1-S1 spine height were measured from posteroanterior radiographs. The number of lengthenings, age at implantation, years of follow-up, and complications were also acquired from the registry or patient charts.

RESULTS

Mean age at implantation of the Vertical Expandable Prosthetic Titanium Rib device was 6.34 years. Mean preoperative Cobb angle was 66.3°. Average follow-up was 5.2 years. Mean postoperative Cobb angle was 60.8° after an average of 7.75 lengthening procedures (range, 2-16 procedures). T1-S1 height increased in all patients. There were 17 complications in 8 patients (device migration in 6, wound dehiscence in 3, rod breakage in 2, medical issues in 5, and 1 revision for progression of curve). Of the 17 complications, 10 were grade I, 1 was grade II, and 6 were grade IIA; there were no grade III complications.

CONCLUSIONS

The use of rib-based distraction is an effective and relatively safe method of stabilizing curve progression through growth in severe dysplastic scoliosis associated with NF-1.

Risk factors for surgical site infection following pediatric spinal deformity surgery: a systematic review and meta-analysis

PURPOSE

This study was conducted to identify risk factors for postoperative infection after pediatric spinal deformity surgery.

METHODS

A systematic electronic literature search from inception to November 2014 was performed in the following databases: Pubmed, Embase, and Cochrane library databases. Pooled odds ratios (ORs) or standardized mean differences (SMDs) with 95 % confidence intervals (CIs) were calculated using random or fixed effects model. Newcastle-Ottawa scale was used to evaluate the methodological quality, and Stata 11.0 was used to analyze data.

RESULTS

The main factors associated with infection after spinal surgery were idiopathic scoliosis (OR, 0.303; 95 % CI, 0.202-0.453), neuromuscular scoliosis (OR, 2.269; 95 % CI, 1.576-3.267), ambulatory status (OR, 0.241; 95 % CI, 0.078-0.747), previous spinal surgery (OR, 4.564; 95 % CI, 1.892-11.009), sacral vertebrae fused (OR, 2.717; 95 % CI, 1.836-4.020), and allograft (OR, 8.498; 95 % CI, 4.030-17.917). There was no sufficient evidence to reveal that male gender, age, body mass index, preoperative curve, preoperative urinary tract infection, combined anterior-posterior approach, estimated blood loss, and operating room time could lead to infection after spinal surgery.

CONCLUSIONS

We identified some risk factors which could be used to prevent the onset of surgical site infection in pediatric spinal deformity surgery. However, the results of this meta-analysis should be interpreted with caution because of the heterogeneity among the studies.

[Non-fusion techniques for treatment of pediatric scoliosis]

The primary goal of treatment in children with early onset scoliosis (EOS) is to control the deformity and to allow spinal and chest wall growth to continue and improve pulmonary function. In skeletally immature children spondylodesis leads to fusion of the instrumented segments with associated nonsymmetrical growth and pulmonary insufficiency. Non-fusion, techniques such as growing rods, vertical expandable prosthetic titanium rib® (VEPTR) and staples have evolved over the past years. Each technique has its different spectrum of indications which the surgeon has to follow accurately to prevent the patient from developing complications. A new trend started by using magnetically controlled growing rods to avoid the need for anesthesia and open surgery during adaptive growth. The intention of this article is to give the reader a synopsis about the three most important non-fusion techniques based on own experience and the current literature.

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.

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.