Predicting early return to the operating room in early-onset scoliosis patients using machine learning techniques.

PURPOSE: Surgical treatment of early-onset scoliosis (EOS) is associated with high rates of complications, often requiring unplanned return to the operating room (UPROR). The aim of this study was to create and validate a machine learning model to predict which EOS patients will go on to require an UPROR during their treatment course. METHODS: A retrospective review was performed of all surgical EOS patients with at least 2 years follow-up. Patients were stratified based on whether they had experienced an UPROR. Ten machine learning algorithms were trained using tenfold cross-validation on an independent training set of patients. Model performance was evaluated on a separate testing set via their area under the receiver operating characteristic curve (AUC). Relative feature importance was calculated for the top-performing model. RESULTS: 257 patients were included in the study. 146 patients experienced at least one UPROR (57%). Five factors were identified as significant and included in model training: age at initial surgery, EOS etiology, initial construct type, and weight and height at initial surgery. The Gaussian naïve Bayes model demonstrated the best performance on the testing set (AUC: 0.79). Significant protective factors against experiencing an UPROR were weight at initial surgery, idiopathic etiology, initial definitive fusion construct, and height at initial surgery. CONCLUSIONS: The Gaussian naïve Bayes machine learning algorithm demonstrated the best performance for predicting UPROR in EOS patients. Heavier, taller, idiopathic patients with initial definitive fusion constructs experienced UPROR less frequently. This model can be used to better quantify risk, optimize patient factors, and choose surgical constructs. LEVEL OF EVIDENCE: Prognostic: III.

[Growth-preserving instrumentation for early onset scoliosis]. / Mitwachsende Korrektursysteme bei Early-Onset-Skoliosen.

OBJECTIVE: Early onset scoliosis is defined as a spinal deformity originating in the first 10 years of life. Growth-preserving spinal instrumentation has therefore been designed to preserve growth of spine and chest wall and lungs to avoid serious pulmonary complications after early spine fusion. Indications, surgical technique and results of the vertical expandable prosthetic titanium rib (VEPTR) technique, traditional growing rods (TGR), and magnetically controlled growing rods (MCGR) will be described. INDICATIONS: Indications for VEPTR are so-called mixed congenital deformities (type 3) associated with vertebral malformations in association with chest wall deformities, especially fused ribs. There are also indications for neuromuscular or syndromic early onset scoliosis with bilateral rib-to-ilium constructs. However, most of those deformities are currently treated with either GR or MCGR in most centers. GR and MCGR are currently the treatment of choice for the majority of early onset scoliosis. CONTRAINDICATIONS: There is no indication for growth-preserving strategies if the patients are mature or there is only little growth remaining. In these cases, final fusion should be performed. SURGICAL TECHNIQUE: While the VEPTR technique involves an extensive approach with muscular dissections to the thoracic cage including rib osteotomies and thoracotomies, treatment with TGR or MCGR is minimally invasive, only exposing proximal and distal anchor points, leaving most of the spine including the apex undisturbed. POSTOPERATIVE MANAGEMENT: Early mobilization is usually possible after 24-48 h. Braces may have to be prescribed for patients with osteopenia, noncompliance, or a risk to fall. RESULTS: Since 2005, more than 200 patients were treated with the VEPTR technique, more than 200 patients with the MCGR technique, and about 30 patients with the TGR technique in our department. Complication rates are high with all techniques including the law of diminishing returns, autofusion, bone anchor-related complications like loosening or migration of implants, failure to distract and proximal junctional kyphosis. In our own series of 13 patients below age 3 years, VEPTR proved to be effective for mixed deformities. In other studies, we were able to show that physiological growth with MCGR can be maintained for 2-3 years but spinal growth declines after that period with acceptable complications. Complication rates in most studies are lower with MCGR compared to TGR and VEPTR. Therefore, it is currently the treatment of choice for most early onset scoliosis patients.

Update on the Diagnosis and Management of Early-onset Scoliosis.

PURPOSE OF REVIEW: In this article, we review the most recent advancements in the approaches to EOS diagnosis and assessment, surgical indications and options, and basic science innovation in the space of early-onset scoliosis research. RECENT FINDINGS: Early-onset scoliosis (EOS) covers a diverse, heterogeneous range of spinal and chest wall deformities that affect children under 10 years old. Recent efforts have sought to examine the validity and reliability of a recently developed classification system to better standardize the presentation of EOS. There has also been focused attention on developing safer, informative, and readily available imaging and clinical assessment tools, from reduced micro-dose radiographs, quantitative dynamic MRIs, and pulmonary function tests. Basic science innovation in EOS has centered on developing large animal models capable of replicating scoliotic deformity to better evaluate corrective technologies. And given the increased variety in approaches to managing EOS in recent years, there exist few clear guidelines around surgical indications across EOS etiologies. Despite this, over the past two decades, there has been a considerable shift in the spinal implant landscape toward growth-friendly instrumentation, particularly the utilization of MCGR implants. With the advent of new biological and basic science treatments and therapies extending survivorship for disease etiologies associated with EOS, the treatment for EOS has steadily evolved in recent years. With this has come a rising volume and variation in management options for EOS, as well as the need for multidisciplinary and creative approaches to treating patients with these complex and heterogeneous disorders.

Growth friendly surgeries increase 3D true spine length at two-years post-operative.

PURPOSE: Traditional coronal-plane vertical spine height measurements, such as T1-T12 and T1-S1 spine height, are influenced by 3-dimensional spinal deformity. Therefore, they are unreliable indicators of true spine growth. The novel 3D true spine length (3D-TSL) technique assesses spine growth regardless of the presence of 3D spinal deformity. This study evaluates the effect of growth friendly surgery on spine growth using the 3D-TSL technique at two years follow-up. METHODS: Radiographs of early onset scoliosis (EOS) participants undergoing growth friendly surgery at a single institution were evaluated at pre-index, post-index, and at 2-year follow-up. Scoliosis, kyphosis, traditional coronal height and 3D-TSL were measured. RESULTS: Twenty-four EOS patients (14 female) with a mean age of 6.3 years were included. Scoliosis improved from 77.8 ± 18.7° pre-index to 56.0 ± 17.8° post-index (p < 0.001); but increased at 2 years to 65.9 ± 20.1° (p < 0.05). Kyphosis improved from 56.0 ± 20.7° pre-index to 39.3 ± 13.8° post-index (p < 0.001); and increased again at 2 years to 48.6 ± 16.4° (p < 0.05). Traditional T1-S1 height increased from pre-index to post-index, to 2-year follow-up (245.5 ± 37.2 mm to 275.8 ± 42.7 mm; p < 0.001, to 288.0 ± 41.7 mm; p = 0.005). As expected, T1-S1 3D-TSL did not change from pre to immediately post-index (305.6 ± 43.9 mm vs 306.5 ± 44.0 mm); there was a significant change from post-index to 2-year follow-up (334.1 ± 48.0 mm; p < 0.001). CONCLUSIONS: Out of plane changes in scoliosis and kyphosis over time justify the use of the 3D-TSL for this cohort of patients. There was no significant change in 3D-TSL from pre-index to post-operatively; however, during the growth phase of treatment 3D-TSL increased significantly by 27.6 mm.

Preoperative left shoulder elevation > 1 cm is predictive of severe postoperative shoulder imbalance in early onset idiopathic scoliosis patients treated with growth-friendly instrumentation.

PURPOSE: Prior research has demonstrated the influence of preoperative shoulder elevation (SE), proximal thoracic curve magnitude, and upper instrumented vertebra (UIV) on shoulder balance after PSF for AIS. Our purpose was to evaluate the impact of these factors on shoulder balance in early onset idiopathic scoliosis (EOIS) patients treated with growth-friendly instrumentation. METHODS: This was a multicenter retrospective review. Children with EOIS treated with dual TGR, MCGR, or VEPTR and minimum 2-year follow-up were identified. Demographics and radiographic/surgical data were collected. RESULTS: 145 patients met inclusion criteria: 74 had right SE (RSE), 49 left SE (LSE), and 22 even shoulders (EVEN) preoperatively. Mean follow-up was 5.3 years (range, 2.0-13.1 years). The LSE group had a larger pre-index mean main thoracic curve (p = 0.021) but no difference was observed between groups at the post-index or most recent timepoints. RSE patients with UIV of T2 were more likely to have balanced shoulders post-index than patients with UIV of T3 or T4 (p = 0.011). Pre-index radiographic shoulder height (RSH) was predictive of post-index shoulder imbalance ≥ 2 cm in the LSE group (p = 0.007). A ROC curve showed a cut-off of 1.0 cm for RSH. 0/16 LSE patients with pre-index RSH < 1.0 cm had post-index shoulder imbalance ≥ 2 cm compared to 8/28 (29%) patients with pre-index RSH > 1.0 cm (p = 0.006). CONCLUSION: Preoperative LSE > 1.0 cm is predictive of shoulder imbalance ≥ 2 cm after insertion of TGR, MCGR, or VEPTR in children with EOIS. In patients with preoperative RSE, UIV of T2 resulted in a higher likelihood of balanced shoulders postoperatively.

Patient-specific 3D printing to replace components of a rib-to pelvis "Eiffel Tower" vertebral expanding prosthetic titanium rib system in an infant: a case report.

PURPOSE: To address the anatomical challenges facing complex and revision spinal surgery, patient-specific 3D-printed models (3D-PMs) have received growing attention worldwide, primarily in adults. We report the use of a 3D-PM in the treatment of a case of wound breakdown over a component of a VEPTR (Vertical Expandable Prosthetic Titanium Rib; DePuy-Synthes) system, requiring replacement of Dunn-McCarthy hook and sleeve with components contoured to a patient-specific 3D-PM of the spine. METHOD: A two-year-old born with myelomeningocele (MMC), repaired at birth, developed progressive MMC-associated kyphoscoliosis. Elective insertion of a rib-to-pelvis 'Eiffel Tower' bilateral VEPTR growing rods construct was performed without initial complication. Prominence of the right VEPTR sleeve and Dunn-McCarthy hook side-to-side connector resulted in breakdown of overlying poor-quality soft tissues, necessitating washout, partial implant removal, intravenous antibiotic therapy and delayed primary wound closure. A patient-specific 3D-PM, utilising pre-operative CT spine and pelvis 3D-reconstructions, allowed pre-operative formation of a contoured implant, which was inserted without need for further revision. RESULTS: The patient underwent further VEPTR lengthening without recurrent infection, wound breakdown or implant failure at 24-month follow-up. Satisfactory control of the deformity has been achieved with continued improvement in sitting height and radiographic indices. CONCLUSION: This case illustrates the possibility, in certain cases, of using 3D-PM to develop complex components of spinal implant systems pre-operatively, removing the time and difficulty of intra-operative contouring. Consequently, custom-contoured implants may be produced, sterilised and implanted. This technique may be an option, in infants, including MMC-associated kyphoscoliosis, where midline fixation is not possible.

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.

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.

Outcome of Vertical Expandable Prosthetic Titanium Rib (VEPTR) Instrumentation in Scoliosis Associated With 1p36 Deletion Syndrome: A Case Report.

Monosomy 1p36 deletion is a rare syndrome that consists of developmental delay, intellectual disability, seizures, hearing and vision defects, brain anomalies, orofacial clefting, congenital heart defects, cardiomyopathy, renal anomalies, and scoliosis. We report the case of an eight-year-old boy who presented to the orthopedic clinic with spinal deformity with a background of 1p36 deletion syndrome. The treatment modalities at this age include growing rods, vertical expandable prosthetic titanium rib (VEPTR), or posterior spinal fusion. Keeping in view the challenges in this case due to multi-organ involvement and severe intellectual disability, we decided to manage this patient with a VEPTR device to prevent the progression of scoliosis and allow spinal growth. Vertical expandable prosthetic titanium rib (VEPTR) instrumentation for progressive scoliosis in p36 deletion syndrome is an effective mode of treatment and leads to favorable outcomes.

Scoliosis flexibility correlates with post-operative outcomes following growth friendly surgery.

PURPOSE: The purpose of this study was to determine the relationship between pre-operative scoliosis flexibility and post-operative outcomes, including curve correction and complications, for patients who have been treated with growth friendly surgery (GFS) for early onset scoliosis (EOS). METHODS: The study was conducted as a retrospective review of prospectively collected data from an international, multicenter, EOS database. EOS patients with pre-operative flexibility radiographs (traction or bending) were identified. Pre-operative flexibility and immediate post-operative correction were calculated for each patient. Post-operative complications were recorded at final follow-up. Pearson correlations were determined for flexibility vs correction for all patients and were compared between etiologies and between device types (MCGR, TGR, VEPTR). RESULTS: 107 patients (14 congenital, 43 neuromuscular, 31 syndromic, 19 idiopathic) with mean age 7.1 years at index surgery were identified. Mean pre-operative scoliosis was 77°. Mean flexibility of 36% was not significantly different between etiologies. Mean immediate post-operative scoliosis was 46° (p < 0.001 vs. pre-operative) with mean correction of 38%. Correction rate was not significantly different between etiologies; however, correction rate was different between device types (MCGR 45%, TGR 40%, VEPTR 14%; p = < 0.001). Pearson correlation for flexibility vs correction was fair (r = 0.37, p < 0.001). This correlation was observed for idiopathic (r = 0.53, p = 0.020) and neuromuscular (r = 0.46, p = 0.0020) scoliosis, but not for congenital or syndromic scoliosis. At a mean of 6.1 year follow-up (minimum 2 years to 15.5 years), 60 of 81patients (74%) experienced at least one complication. Odds ratio for developing a complication was 3.00 (1.03-8.76) for patients with pre-operative flexibility < 45% (p < 0.05). CONCLUSIONS: As lower pre-operative flexibility was associated with less scoliosis correction and with a higher risk of post-operative complications, curve flexibility should be considered when deciding upon the timing of growth friendly surgery. LEVEL OF EVIDENCE: Level III-retrospective comparative study.

Pelvic fixation is not always necessary in children with cerebral palsy scoliosis treated with growth-friendly instrumentation.

PURPOSE: A previous study showed that patients with neuromuscular scoliosis who underwent fusion to L5 had excellent coronal curve correction and improvement in pelvic obliquity (PO) when preoperative L5 tilt was < 15°. Our purpose was to identify indications to exclude the pelvis in children with cerebral palsy (CP) scoliosis treated with growing-friendly instrumentation. METHODS: In a retrospective cohort study, children with CP scoliosis treated with TGR, MCGR, or VEPTR with minimum 2-year follow-up were identified from a multicenter database. RESULTS: 27 patients with distal spine anchors (DSA) and 71 patients with distal pelvic anchors (DPA) placed at the index surgery were analyzed. The DSA group had a lower pre-index PO (9° vs 16°, P = 0.0001). Most recent radiographic data were similar except the DSA patients had a smaller major curve (47° vs 58°, P = 0.038). 6 (22%) DSA patients underwent extension of the instrumentation to the pelvis (DSA-EXT), most commonly at final fusion (5 patients). DSA-EXT patients had a higher pre-index L5 tilt than patients who did not require extension (DSA-NO EXT) (19° vs 10°, P = 0.009). Sub-analysis showed a lower major curve at most recent follow-up in the DSA-EXT group compared to the DPA group (33° vs 58°, P = 0.021). The DSA-EXT group had a higher number of complications per patient compared to the DSA-NO EXT group (2.3 vs 1.1, P = 0.029). CONCLUSION: Pre-index L5 tilt ≤ 10° and PO < 10° may be indications to exclude the pelvis in children with CP scoliosis treated with growth-friendly instrumentation. DSA may provide better long-term control of the major curve than DPA.

Final fusion in a complex of surgical treatment for early onset scoliosis.

INTRODUCTION: Surgical treatment of early onset scoliosis (EOS) is one of the most challenging problems of spine surgery and includes staged distraction and final fusion at the end of skeletal maturity that remains debatable. AIM: The objective of the review is to evaluate the efficacy of final fusion following staged distraction with VEPTR instrumentation in patients with EOS. MATERIALS AND METHODS: Outcomes of multi-staged operative treatment of 37 patients with EOS of different etiology were reviewed. Medical records and radiographs of the patients were retrospectively analyzed. Standing postero-anterior and lateral spine radiographs were used for the spinal radiologic assessment before and after each stage of distraction-based treatment, before and after final fusion and at the last follow-up. RESULTS: The mean age of patients at baseline was 5.2 years and the mean age at final fusion was 13.9 years. All patients demonstrated decrease in the angle of primary (from 81.5° to 51.6°) and secondary (from 59.3° to 37.8°) curves, increase of the height and normalized body balance. The mean height increased from 104.8 cm to 141.0 cm, and the mean weight increased from 15 kg to 35 kg throughout the treatment period. The height of the thoracic and lumbar vertebra (Th1-S1) increased from 245 mm to 340 mm, and that of the thoracic vertebra - from 136 mm to 193 mm. There was a mean of 2.3 complications per patient during distraction performed in a staged manner, and they were arrested during elective procedures. There were 7 (19%) complications after final fusion that required 6 (16%) unplanned revisions. Radiologic evidence of spontaneous autofusion was seen in the lumbar spine of the patients with the inferior anchor at the lumbar vertebra. CONCLUSIONS: Multi-staged pediatric surgeries performed in the first decade of life facilitate radical changes in the natural history of progressive scoliosis and ensure satisfactory functional and cosmetic results despite multiple difficulties and complications. The VEPTR instrumentation used for the thoracic curve is unlikely to result in the spinal fusion of the major arch and this is the cause for the use of third-generation instrumented final spinal fusion in the patients.

Outcomes of Vertical Expandable Prosthetic Titanium Ribs in Children With Early-Onset Scoliosis Secondary to Cerebral Palsy.

Purpose Patients who have neuromuscular scoliosis, such as cerebral palsy (CP), often develop spinal deformities that negatively impact quality of life. The vertical expandable prosthetic titanium rib (VEPTR) was designed for thoracic insufficiency syndrome (TIS), but it has also been utilized in patients with CP with restrictive lung disease and spine deformity. Few studies report on VEPTRs in neuromuscular scoliosis; however, none reports on their utilization specifically in patients with CP. Our purpose was to assess if VEPTRs can improve spinal deformity and TIS in these patients. Methods A retrospective chart review was performed of all patients with CP and scoliosis treated with a VEPTR between 2008 and 2017. Eight patients were eligible for this study. The mean follow-up was four years. Outcomes evaluated were Cobb angle, pelvic obliquity, space available for lung ratio (SAL), T1-S1 height, and complication rates. A p-value of less than 0.05 was used for statistical significance. Results There were significant postoperative improvements in Cobb angle, pelvic obliquity, and T1-S1 height, but no statistical difference in SAL. Prior to final fusion, the mean number of VEPTR lengthening procedures was 3. The mean time from index surgery to final fusion was 3.7 years. The most common complications were infection (62.5%) and wound dehiscence (25%). Only 25% of patients did not have a complication. Conclusion VEPTRs demonstrated significant improvement in almost all parameters and may be valuable in improving TIS in patients with CP. The complication and reoperation rates were similar to those of VEPTRs used for other pathological conditions.

Early Complications in Vertical Expandable Prosthetic Titanium Rib and Magnetically Controlled Growing Rods to Manage Early Onset Scoliosis.

OBJECTIVES: The aim of this study is to examine whether surgical treatment of early onset scoliosis (EOS) with magnetically controlled growing rods (MCGRs) or a vertical expandable prosthetic titanium rib (VEPTR) resulted in fewer short-term (24 months) complications and reoperations. BACKGROUND: EOS is a challenging problem for spine surgeons that has been managed with different growth-friendly instrumentation systems. Although rib-based devices encourage spinal growth via regular lengthening, the high rate of complications and reoperations leads us to use spine-based devices such as MCGRs to mitigate this concern. METHODS: A total of 35 EOS patients were included in the study. Twenty patients were included in the VEPTR group, and 15 patients were included in the MCGR group. Demographic data and 2 years of postoperative complications and reoperations were reviewed retrospectively. As secondary outcomes, radiographic outcomes were reported preoperatively and 1 year after surgery. Indications for this technique and complications were collected from the charts. RESULTS: Demographic data showed no significant differences between the 2 groups. Significant differences were found in the complications rate at 2 years, with 65% complications in the VEPTR group and 13.3% complications in the MCGR group (P < .001). The reoperation rate at 2 years was also significantly higher in the VEPTR group, with 50% versus 13.3% in the MCGR group (P = .0009). As secondary outcomes, radiological parameters such as main curve Cobb angle correction (P = .001) and apical vertebral translation (P = .002) were significantly higher in the MCGR group. Significant differences were also found in sagittal profile parameters; T1-T12 and T1-S1 were significantly higher in the MCGR group (P < .001). CONCLUSIONS: According to our results, VEPTR has significantly higher complication and reoperation rates at 2 years postsurgery compared with MCGR. LEVEL OF EVIDENCE: 4.

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.

Can distraction-based surgeries achieve minimum 18 cm thoracic height for patients with early onset scoliosis?

PURPOSE: Karol et al. introduced the concept that 18 cm thoracic height is the critical point where a patient with early onset scoliosis (EOS) can maintain adequate pulmonary function. Our purpose was to determine if distraction-based surgeries will increase thoracic spine height to at least 18 cm in patients with EOS. METHODS: Patients with EOS treated with distraction-based systems (minimum 5 years follow up, minimum five lengthenings). Radiographic analysis of thoracic spine height (T1-T12) at the last lengthening procedure. RESULTS: One hundred and fifty-three patients (67 congenital, 21 neuromuscular, 38 syndromic, 27 idiopathic) with pre-operative mean age 4.6 years, scoliosis 75°, kyphosis 47° were evaluated. Their mean age at final lengthening procedure was 11 years (6-16), average number of lengthening procedures was 10.5 (4-21), mean final scoliosis was 53°, and mean final kyphosis was 58°. Final thoracic height was > 18 cm in 65% and was > 22 cm in 31% of patients. Based on etiology, only 48% of the congenital patients reached 18 cm compared to 81% neuromuscular, 84% syndromic and 67% idiopathic. This height gain was closely related to the percentage of scoliosis correction achieved for each etiology. Comparing congenital etiology to other etiologies, there was a lower percentage of patients in the congenital group that passed the 18 cm threshold (48% vs. 78%) (p < 0.05). CONCLUSION: At minimum 5 years follow up, distraction-based surgeries increased thoracic height for patients with EOS to greater than 18 cm in 65% of patients; however, only 48% of congenital patients reached this thoracic height threshold. DESIGN: Retrospective review of prospectively collected registry data. LOI III.

Anesthesia for Innovative Pediatric Surgical Procedures.

Over the past few decades, there have been many advances in pediatric surgery, some using new devices (eg, VEPTR, MAGEC rods) and others using less invasive approaches (eg, Nuss procedure, endoscopic cranial suture release, minimally invasive tethered cord release). Although many of these procedures were initially met with caution or skepticism, continued experience over the past few decades has shown that these procedures are safe and effective. This article reviews the anesthetic considerations for these conditions and procedures.

Correlation between surgical site infection and classification of early onset scoliosis (C-EOS) in patients managed by rib-based distraction instrumentation.

OBJECTIVES: The aim of this study is to determine risk factors for infection among EOS patients treated by rib-based distraction instrumentation, and to further assess the incidence of infection among C-EOS categories and sub-types. Despite the heterogonous nature of early onset scoliosis, the classification of early onset scoliosis (C-EOS) has proven to have excellent reliability across its major categories. C-EOS's reliability has been verified; however, little data exist on the utility of this categorization in clinical decision-making and risk assessment. METHODS: After institutional review board approval, data for EOS patients treated by rib-based distraction instrumentation were collected between 2013 and 2017 in a single institution. Data collection included: major categories of early onset scoliosis classification (etiology, major curve and kyphosis), BMI, height, weight, procedure type, site of procedure, presence of tracheostomy, and bowel/urinary incontinence. RESULTS: 156 EOS patients underwent 843 rib-based distraction instrumentation procedures. 22.4% of patients (35/156 patients, 42 procedures) developed infections, 30/35 requiring irrigation and debridement. Type of procedure was significantly associated with infection rate, with rib-based distraction instrumentation insertion corresponding with the highest incidence of infection, as compared to instrumentation revisions or expansions (p = 0.006). Infection rates were also more common in shorter and lighter weight children (p = 0.001 and 0.03; respectively). Patients with a neuromuscular etiology had the highest rate of infection in comparison to congenital, syndromic, and idiopathic (5.7% vs, 4.9%, 4.7%, and 2.6%; respectively). Notably, high infection rates occurred neuromuscular hyper-kyphotic subjects (M+), occurring in all major curve C-EOS subgroups and at a rate of 8.3% for all procedures. CONCLUSION: Neuromuscular, larger magnitude major curve, and larger magnitude kyphotic angle C-EOS categories appear to be at a higher risk of infection. Such information potentiates the usefulness of C-EOS in surgical decision-making and in the informed consent process. LEVEL OF EVIDENCE: Level III therapeutic.

Five or more proximal anchors and including upper end vertebra protects against reoperation in distraction-based growing rods.

STUDY DESIGN: Retrospective multi-center enrollment. OBJECTIVE: To examine the impact of patient and surgical factors on proximal complication and revision rates of early onset scoliosis patients using a multicenter database. Proximal anchor pullout and junctional kyphosis are common causes necessitating revision surgery during growth friendly treatment of early onset scoliosis (EOS). Many options exist for proximal fixation and may impact the rate of these complications. METHODS: Retrospective review of multicenter database of patients with growth friendly constructs for EOS. Inclusion criteria were patients with index instrumentation < 10 years of age and minimum of 2 year follow-up. RESULTS: 353 patients met the inclusion criteria and had the following constructs: growing rods with spine anchors = 303; growing rods with rib anchors = 15 and VEPTR = 35. Mean age at index instrumentation was 6.0 years. Mean preoperative Cobb angle was 76° and mean kyphosis was 54°. Mean follow-up was 6.0 years. 21.8% of patients (77/353) experienced anchor pullout. Lower anchor pullout rates were associated with a higher numbers of proximal anchors (p = 0.003, r = - 0.157), and 5 or more anchors were associated with lower rates of anchor pullout (p = 0.014). Anchor type (rib hooks vs spine anchors vs rib cradle) did not impact rate of anchor pullout (p = 0.853). Kyphosis data was available for 198 patients. 23.2% (46/198) of these patients required proximal extension of their construct after index surgery. Initial instrumentation below the upper end vertebrae (UEV) of kyphosis was associated with higher rates of subsequent proximal revision; 28.9% (20/69) compared to 20.1% (26/129) for those instrumented at or above the UEV (p = 0.035). Preoperative kyphosis and change in thoracic kyphosis were not associated with anchor pullout (p = 0.436, p = 0.115) or proximal revision rates (p = 0.486, p = 0.401). CONCLUSION: Five or more anchors are associated with lower rates of anchor pullout. Proximal anchor placement at or above the UEV resulted in a significant decrease in rates of proximal extension of the construct.

Children With Spinal Muscular Atrophy With Prior Growth-Friendly Spinal Implants Have Better Results After Definite Spinal Fusion in Comparison to Untreated Patients.

BACKGROUND: Almost all children with spinal muscular atrophy (SMA) develop a scoliosis during childhood and adolescence. In the last decades, growth-friendly spinal implants have been established as an interim solution for these patients until definite spinal fusion can be performed. The effect of those implants on the final outcome has yet to be described. OBJECTIVE: To assess the effect of prior growth-friendly spinal surgical treatment on the outcome after spinal fusion in SMA children in comparison to untreated SMA patients through the prospective study. METHODS: A total of 28 SMA patients with (n = 14) and without (n = 14) prior surgical treatment with growth-friendly implants were included. Average surgical treatment prior to definite spinal fusion was 4.9 yr. Scoliotic curve angle, pelvic obliquity, spinal length, kyphosis, and lordosis were evaluated for children with prior treatment and before and after dorsal spondylodesis for all children. RESULTS: The curve angle before definite spinal fusion averaged at 104° for SMA patients without prior treatment and 71° for patients with prior treatment. Spondylodesis reduced the scoliotic curve to 50° and 33°, respectively, which equals a correction of 52% vs 54%. Pelvic obliquity could be improved by spinal fusion in all patients with better results in the pretreated group. Results for spinal length, kyphosis, and lordosis were similar in both groups. CONCLUSION: These data show the positive effect of prior growth-friendly surgical treatment on radiographic results of spinal fusion in children with SMA. Both scoliotic curve angles and pelvic obliquity showed significantly better values when patients had growth-friendly implants before definite spinal fusion.