More experienced surgeons less likely to fuse: a focus group review of 315 hypothetical EOS cases

Automated Clustering Technique (ACT) for Early Onset Scoliosis: A preliminary report

PURPOSE

While the C-EOS system helps organize and classify Early Onset Scoliosis (EOS) pathology, it is not data-driven and does not help achieve consensus for surgical treatment. The current study aims to create an automated method to cluster EOS patients based on pre-operative clinical indices.

METHODS

A total of 1114 EOS patients were used for the study, with the following distribution by etiology: congenital (240), idiopathic (217), neuromuscular (417), syndromic (240). Pre-operative clinical indices used for clustering were age, major curve (Cobb) angle, kyphosis, number of levels involved in a major curve (Cobb angle) and kyphosis along with deformity index (defined as the ratio of major Cobb angle and kyphosis). Fuzzy C-means clustering was performed for each etiology individually, with one-way ANOVA performed to assess statistical significance (p < 0.05).

RESULTS

The automated clustering method resulted in three clusters per etiology as the optimal number based on the highest average membership values. Statistical analyses showed that the clusters were significantly different for all the clinical indices within and between etiologies. Link to the ACT-EOS web application: https://biomed.drexel.edu/labs/obl/toolkits/act-eos-application .

CONCLUSION

An automated method to cluster EOS patients based on pre-operative clinical indices was developed identifying three unique, data-driven subgroups for each C-EOS etiology category. Adoption of such an automated clustering framework can help improve the standardization of clinical decision-making for EOS.

Magnetically Controlled Growing Rods (MCGR) Versus Single Posterior Spinal Fusion (PSF) Versus Vertebral Body Tether (VBT) in Older Early Onset Scoliosis (EOS) Patients: How Do Early Outcomes Compare?

STUDY DESIGN

Retrospective review of prospective data from multicenter registry.

OBJECTIVE

Compare outcomes of posterior spinal fusion (PSF) versus magnetically controlled growing rods (MCGR) versus vertebral body tethers (VBT) in 8- to 11-year-old idiopathic early onset scoliosis (EOS) patients.

SUMMARY OF BACKGROUND DATA

In EOS, it is unclear at what age the benefit of growth-sparing strategies outweighs increased risks of surgical complications, compared with PSF.

METHODS

One hundred thirty idiopathic EOS patients, 81% female, aged 8-11 at index surgery (mean 10.5 yrs), underwent PSF, MCGR, or VBT. Scoliosis curve, kyphosis, thoracic and spinal height, complications, and Quality of Life (QoL) were assessed preoperatively and at most recent follow-up (prior to final fusion for VBT/MCGR).

RESULTS

Of 130 patients, 28.5% received VBT, 39.2% MCGR, and 32.3% PSF. The VBT cohort included more females (P < 0.0005), was older (P < 0.0005), more skeletally mature (P < 0.0005), and had smaller major curves (P < 0.0005). At follow-up, scoliosis curve corrected 41.1 ± 22.4% in VBT, 52.2 ± 19.9% in PSF, and 27.4 ± 23.9% in MCGR (P < 0.0005), however, not all VBT/MCGR patients finished treatment. Fifteen complications occurred in 10 VBTs, 6 requiring unplanned surgeries; 45 complications occurred in 31 MCGRs, 11 requiring unplanned surgeries, and 9 complications occurred in 6 PSFs, 3 requiring unplanned revisions. Cox proportional hazards regression adjusted for age, gender, and preoperative scoliosis curve revealed that MCGR (hazard ratio [HR] = 21.0, 95% C.I. 4.8-92.5; P < 0.001) and VBT (HR = 7.1, 95% C.I. 1.4-36.4; P = 0.019) patients were at increased hazard of requiring revision, but only MCGR patients (HR = 5.6, 95% C.I. 1.1-28.4; P = 0.038) were at an increased hazard for unplanned revisions compared with PSF. Thoracic and spinal height increased in all groups. QoL improved in VBT and PSF patients, but not in MCGR patients.

CONCLUSION

In older idiopathic EOS patients, MCGR, PSF, and VBT controlled curves effectively and increased spinal height. However, VBT and PSF have a lower hazard for an unplanned revision and improved QoL.Level of Evidence: 3.

The Effect of Surgeon Experience on Outcomes Following Growth Friendly Instrumentation for Early Onset Scoliosis

BACKGROUND

The purpose of this study was to utilize a multicenter, multisurgeon cohort to assess the effect of surgeon experience on outcomes of growth friendly instrumentation (GFI) in early onset scoliosis (EOS). We hypothesized that unplanned return to the operating room (UPROR), estimated blood loss (EBL), and surgical time would be greater amongst early career surgeons (ECSs) when compared with advanced career surgeons (ACSs).

METHODS

An international pediatric spine database was queried for patients ages 2 to 10 years treated by posterior distraction-based GFI with at least of 2-year follow up. Two groups were created for analysis based on surgeon experience: ECSs (with ≤10 y of experience) and ACSs (with >10 y of experience). The primary outcome was UPROR. Additional outcomes included: operating room time, EBL, neurological deficits, infection rate, hardware failure, and the Early Onset Scoliosis Questionnaire (EOSQ-24). Subgroup analysis was performed for further assessment based on procedure type, superior anchor type, etiology, and curve severity.

RESULTS

A total of 960 patients met inclusion criteria including 243 (25.3%) treated by ECS. Etiology, sex, superior anchor, and EOSQ-24 scores were similar between groups (P>0.05). There were no clinically significant differences in patient age or preoperative major coronal curve. UPROR (35.8% vs. 32.7%, P=0.532), infection (17.0% vs. 15.6%, P=0.698), operating room time (235 vs. 231 min, P=0.755), and EBL (151 vs. 155 mL, P=0.833) were comparable between ECS and ACS groups. The frequency of having at least 1 complication was relatively high but comparable among groups (60.7% vs. 62.6%, P=0.709). EOSQ-24 subdomain scores were similar between groups at 2-year follow-up (P>0.05). Subgroup analysis revealed that ECS had increased surgical time compared with ACS in severe curves >90 degrees (270 vs. 229 min, P=0.05).

CONCLUSIONS

This study represents the first multicenter assessment of surgeon experience on outcomes in EOS. Overall, surgeon experience did not significantly influence UPROR, complication rates, EBL, or surgical time associated with GFI in this cohort of EOS patients.

LEVEL OF EVIDENCE

Level III.

Effect of Etiology, Radiographic Severity, and Comorbidities on Baseline Parent-Reported Health Measures for Children with Early-Onset Scoliosis

BACKGROUND

The Classification of Early-Onset Scoliosis (C-EOS) allows providers to differentiate patients, for clinical and research purposes, on the basis of the etiology of their disease as well as radiographic parameters. The Early Onset Scoliosis Questionnaire (EOSQ) is the first disease-specific, parent-reported HRQOL (health-related quality-of-life) outcome measure for this condition. We sought to determine the influence of the C-EOS etiology designation, radiographic parameters, and medical comorbidities on EOSQ scores to differentiate quality of life in this heterogeneous patient population. We hypothesized that baseline EOSQ scores for patients with EOS would be strongly affected by the C-EOS etiology designation.

METHODS

The analysis included prospectively enrolled patients with EOSQ scores recorded in a multicenter EOS database prior to intervention for the EOS. EOSQ scores were compared across C-EOS etiologies, severity of disease based on radiographic measurements, and patient comorbidities prior to scoliosis intervention.

RESULTS

Six hundred and ten patients with EOS were available for analysis; 119 had congenital, 201 had idiopathic, 156 had neuromuscular, and 134 had syndromic EOS. In multivariate analysis, neuromuscular and syndromic etiologies were associated with lower scores than congenital and idiopathic etiologies in many EOSQ domains including general health, transfer, daily living, fatigue/energy level, and emotion. Patients with neuromuscular EOS had the lowest EOSQ scores in general. Congenital and idiopathic EOS did not differ from each other in any EOSQ domain. Coronal Cobb and kyphosis angles had significant inverse but generally weak correlations with EOSQ domains. Individual medical comorbidities had a minor effect on certain domains while American Society of Anesthesiologists (ASA) class and total number of comorbidities had inverse correlations with most domains.

CONCLUSIONS

The underlying etiology of EOS appears to have a significant influence on the parent-reported HRQOL outcomes of the disease. Specifically, syndromic and neuromuscular C-EOS diagnoses are associated with lower EOSQ scores before treatment compared with congenital and idiopathic diagnoses. Radiographic measurements of severity have a relatively small influence on EOSQ scores. These baseline differences in C-EOS-designated etiology should be accounted for in studies comparing outcomes of treatment for this heterogeneous patient population.

LEVEL OF EVIDENCE

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

Expert Consensus for Early Onset Scoliosis Surgery

BACKGROUND

Despite a validated classification system, high-quality multicenter research databases (CSSG/GSSG), and a recent proliferation in publications, early-onset scoliosis (EOS) surgeons have no consensus on standards for surgical treatment. The 21st-century revolution in EOS care has only accelerated, with the arrival of a classification system, magnetically controlled growing rod, nusinersen, and improved nonoperative care (Mehta or Risser casting and compliance-monitored braces). This dizzying pace of change may have outstripped our ability to develop best-practice standards for EOS surgical indications. To learn where consensus is best (and worst) at this moment, we surveyed EOS world thought-leaders on a collection of representative cases.

METHODS

A 6-case survey was constructed and sent to 20 EOS world thought-leaders. The cases were selected to be representative of the major treatment categories: idiopathic, neuromuscular, syndromic, congenital, thoracic dysplasia, and spinal muscular atrophy (specifically to assess the impact of nusinersen and parasol deformity on surgical planning). Respondents were queried regarding treatment with specific attention to instrumentation and construct when surgery was selected. Responses regarding surgical timing and technique were analyzed for consensus (defined as >80%). χ analysis was performed to evaluate for differences in treatment preferences based on years of experience.

RESULTS

The survey response was 100%. Clinical experience ranged from 8 to 40 years (average 23.9 y). There was no consensus on any case. The greatest variability was on the congenital case; the closest to consensus was on the spinal muscular atrophy case. Three or more approaches were selected for all 6 cases; >4 approaches were selected for 5 cases. There is a trend towards screw fixation for proximal anchors. The management of thoracic dysplasia and parasol deformity is far from consensus.

CONCLUSION

The lack of consensus for surgical treatment of 6 representative EOS cases demands a renewed effort and commitment to develop best-practice guidelines based on multicenter outcome data.

LEVEL OF EVIDENCE

Level V-Expert Opinion.

Agreement Between Manual and Computerized Designation of Neutral Vertebra in Idiopathic Scoliosis

STUDY DESIGN

Survey-based cross-sectional study.

OBJECTIVES

To describe interobserver agreement among experienced spine surgeons in choosing neutral vertebra (NV) based on manual measurements from radiographs. Secondarily, to use axial vertebral rotation (AVR) values obtained from low-dose stereoradiography (SR) post-processing software (SterEOS 2D/3D) to separately designate the NV in subject cases and to compare manually derived and software-derived NV designations.

SUMMARY OF BACKGROUND DATA

Investigators have previously suggested that parameters such as Lenke classification, stable vertebra level, end vertebra level, and NV level be used to decide on fusion levels in adolescent idiopathic scoliosis (AIS). Studies have revealed suboptimal interobserver reliability in these vertebral designations. SR post-processing software may represent a useful tool for standardizing NV designation.

METHODS

Thirty-two subjects with idiopathic scoliosis and Lenke 1-4 curves were assessed. Experienced surgeons (range of 7-35 years in practice) assigned NV based on preoperative radiographs. Interobserver reliability was quantified using the Fleiss Kappa statistic. Surgeon responses were compared with NV designations made using AVR values provided by SR postprocessing software. Agreement between these values was quantified using percentage agreement.

RESULTS

Surgeons exhibited moderate agreement in choosing NV based on radiographs (Kappa 0.444). Surgeon responses agreed with the SR-derived NV in 26.9% of cases, lay within 1 level in 82.1% of cases, and lay within 2 levels in 97.5% of cases. Surgeons were more likely to choose distal to the SR NV rather than proximal.

CONCLUSIONS

Variability in instrumented level selection and outcomes in idiopathic scoliosis may be partially related to inconsistency in selection of the NV. The use of SR post-processing software may provide a more reliable method for choosing NV.

LEVEL OF EVIDENCE

Level II.

Evaluation of degenerative disease of the lumbar spine: MR/MR myelography versus conventional myelography/post-myelography CT

BACKGROUND

To compare the use of magnetic resonance (MR)/MR myelography (MRM) with conventional myelography/post-myelography CT (convM) for detailed surgery planning in degenerative lumbar disease.

METHODS

Twenty-six patients with suspected complex lumbar degenerative disease underwent MRM in addition to convM as preoperative workup. Surgery was planned based on convM-as usual at our department. Post hoc, surgical planning was repeated planned again-now based on MRM. Furthermore, the MRM-based planning was performed by six independent neurosurgeons (three groups) of different degrees of specialisation.

RESULTS

In only 31 % of the patients, post hoc MRM-based planning resulted in the same surgical decision as originally performed, whereas in 69 % (n = 18) a different procedure was indicated. In patients with non-concurring convM- and MRM-based surgical plans, a less extended procedure was the result of MRM in six patients (23 %), a more extended one in five (19 %), and a related to side/level of decompression or nucleotomy different plan in six patients (23 %). In one patient (4 %), the MRM-based planning would have led to a completely different surgery compared to convM. Overall interobserver agreement on the MRM-based planning was substantial.

CONCLUSIONS

Detailed planning of operative procedures for complex lumbar degenerative disease is highly dependent on the image modality used.

Case-Matched Comparison of Spinal Fusion Versus Growing Rods for Progressive Idiopathic Scoliosis in Skeletally Immature Patients

STUDY DESIGN

Multicenter study of retrospectively and prospectively collected data.

OBJECTIVES

To compare outcomes of spinal fusion (SF) versus growing rod (GR) surgery using a case-matched series.

SUMMARY OF BACKGROUND DATA

Scoliosis surgeons face two distinct treatment options for progressive idiopathic scoliosis in skeletally immature patients: definitive SF or growth-friendly surgery such as GR. No previous studies have directly compared outcomes between these two techniques.

METHODS

A multicenter database identified 11 GR patients who met the following criteria: (1) idiopathic etiology; (2) 9 years to 11 years old at initial surgery; (3) major thoracic curve; (4) had "final" SF. A second multicenter database was used to identify SF patient matches. A one-to-one patient match was performed based on age, major curve size, and curve apex.

RESULTS

Preoperative age was 10.1 years for GR and 10.8 years for SF (P = 0.003). GR had a mean 2.8 lengthenings before final fusion. Follow-up time after spinal fusion (3.8 vs. 4.5 years; P = 0.51) and age at latest follow-up (16.4 vs. 15.3 years; P = 0.28) were similar between GR and SF groups. Initial curve correction was significantly greater for SF compared with GR after initial GR surgery (71% vs. 38%; P < 0.001). SF patients had better overall curve correction at latest follow-up (63% vs. 44%; P = 0.08). Overall increase in T1-S1 was 23% for GR and 19% for SF (P = 0.42). Overall increase in T1-T12 was 19% for GR and 17% for SF (P = 0.76). Complications requiring unplanned surgery occurred in one GR patient and two SF patients. Number of surgeries was significantly higher in GR (54) compared with SF (13).

CONCLUSION

SF patients had greater curve correction and marginally less spinal and thoracic height gain compared with GR patients. GR patients underwent significantly more surgical procedures. These findings suggest GR treatment does not benefit older patients with juvenile idiopathic scoliosis.

LEVEL OF EVIDENCE

4.

Effect of Preoperative Indications Conference on Procedural Planning for Treatment of Scoliosis

STUDY DESIGN

This study determines the rate of change in the scoliosis surgery plan in cases presented in preoperative indications conference.

OBJECTIVES

To determine the effect of preoperative indications conference on the plan of surgery and to identify characteristics that increased the likelihood of change.

SUMMARY OF BACKGROUND DATA

Preoperative indications conferences are used as a teaching and planning tool. Levels of fusion, construct options, and necessity for osteotomies are often debated in the planning of scoliosis surgery.

METHODS

Scoliosis surgeries were presented at preoperative indications conference with four attending pediatric orthopedic surgeons present. The operative surgeon committed to a surgical plan before conference. A consensus-based plan was made without knowledge of the operative surgeon's preconference plan. Changes of plan were classified as major, minor, or no change.

RESULTS

Of the 107 surgical plans, 50 were index surgeries, 13 were revisions, and 44 were scheduled growing rod lengthenings. There were two major changes, including a change to a growing construct from planned fusion, and a change in fusion levels in an adolescent idiopathic scoliosis (AIS) patient. There were 13 minor changes, which included changes in fusion levels (1 to 3; mean = 1.23) and the addition of an osteotomy. The rate of change was 28% for index surgeries and 7.69% for revisions. Of the 14 changes in the 50 index surgeries, there were 8 AIS, 3 cerebral palsy, 1 congenital scoliosis, 1 Ehlers-Danlos, and 1 patient with an undetermined neuromuscular condition. There was 1 change in 13 revision surgeries. There were no changes for growing rod lengthenings and no cancellations as a result of indications conference.

CONCLUSIONS

Although revision scoliosis surgery is complex, index AIS/JIS surgery was most subject to the influence of indications conference. This likely reflects controversy around choosing levels of fusion.

LEVEL OF EVIDENCE

IV.

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.

Low rate of surgery in juvenile idiopathic scoliosis treated with a complete and tailored conservative approach: end-growth results from a retrospective cohort

BACKGROUND CONTEXT

The main distinctive aspect of Juvenile Idiopathic Scoliosis (JIS) with respect to Adolescent Idiopathic Scoliosis (AIS) is the high risk of severe deformity and surgery. Approximately 70% of curves in patients with JIS progress and ultimately require surgery. There are presently very few studies with long-term follow-up of JIS and even fewer looking specifically at bracing Purpose To verify the effectiveness of a complete conservative treatment, including bracing and exercises, for JIS.

STUDY DESIGN/SETTING

Retrospective cohort observational study nested in a clinical prospective database of consecutive outpatients. Patient Sample Inclusion criteria: JIS, no previous treatment, all consecutive radiographies available from treatment start to end of growth (Risser sign 3). We found 30 patients, 27 females, 10 JIS type 1; mean age at first diagnosis was 7.8 +/-1.5 and mean treatment lasted 5.8 years. Cobb degrees 24.4+/-10 degrees, with 7 cases >30 degrees, and 2 > 45degrees. Outcome Measures Physiological measures. Radiographic and clinical data.

METHODS

Treatment (exercises alone, or elastic-rigid-highly rigid braces plus exercises) was tailored and continuously changed according to Cobb degrees, individual preferences, anthropometric characteristics, pubertal spurt, remaining growth, rotation, hump, lumbar curve take-off, and imbalance. The SOSORT Guidelines for patients' management have been followed. Funding and Conflict of Interest: no.

RESULTS

33.3% (95% Confidence Interval 16.4-50.2%) of patients worsened over the years. At the end of growth, 6.6% (0-15.5%) had surgical deformities (>45degrees). We observed a good correction in the first years of treatment until pubertal growth spurt, when progression was usually noted and treatment changed increasing corrective forces (hours or rigidity of bracing). 23 cases were followed up until they had two consecutive radiographies showing Risser sign 5 and showed stability.

CONCLUSIONS

Conservative treatment initiated already in childhood may favorably change the natural history of JIS with the aim of reaching a curve as far as possible from surgical thresholds. Observation, physical exercises, braces can be useful tools in the hand of physicians, but they must be carefully utilized by a deep knowledge of JIS.

Bilateral rib-to-pelvis Eiffel Tower VEPTR construct for children with neuromuscular scoliosis: a preliminary report

BACKGROUND CONTEXT

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

PURPOSE

To demonstrate the preliminary results of the use of VEPTR in an Eiffel Tower construct in children with neuromuscular scoliosis in regard to coronal and sagittal profiles, space available for the lungs (SAL), and spinal growth. The report lists the complications we faced during the follow-up of 1.33 years after the index procedure.

STUDY DESIGN

A retrospective analysis of prospectively collected data of a case series.

PATIENT SAMPLE

Twenty nonambulatory children (mean 8.9 years) with neuromuscular scoliosis. Their primary diagnoses were myelomeningocele in seven, cerebral palsy in three, spinal muscular atrophy in two, myopathies in three, arthrogryposis in one, and syndromic scoliosis in four patients.

METHODS

All 20 patients received percutaneous rib-to-pelvis VEPTR implantation. Mean operative time was 2 hours, and mean hospital stay was 12 days. None of them needed blood transfusion. They underwent 20 primary implantations and 39 lengthenings.

OUTCOME MEASURES

The patients were assessed based on physiologic measures, that is, the radiographic improvement of their scoliosis, SAL, pelvic tilt, spinal height, and sagittal and coronal decompensation.

RESULTS

At the latest follow-up, thoracolumbar curvature improved significantly (65.7°±20.5° to 49.9°±15.7°), as did lumbar curvature (61.6°±19.5° to 35°±21.2°), thoracic (17.2±2.3 to 20±2.3 cm) and lumbar spinal height (9.9±1.7 to 11.9±1.8 cm), SAL (86.5±8.9 to 97±10), pelvic obliquity (12.5°±8° to 5.2°± 5.2°), and the iliolumbar angle (15°±8° to 10.06°±7.1°). Nine patients suffered complications in the form of proximal cradle migration (five), implant breakage (five), deep wound infection (three), and dislodged iliac hooks (two).

CONCLUSIONS

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

[Early onset scoliosis. What are the options?]

The prognosis of children with progressive early onset scoliosis has improved considerably due to recent advances in surgical and non-surgical techniques and the understanding of the importance of preserving the thoracic space. Improvements in existing techniques and development of new methods have considerably improved the management of this condition. Derotational casting can be considered in children with documented progression of a <60° curve without previous surgical treatment. Both single and dual growing rods are effective, but the latter seem to offer better results. Hybrid constructs may be a better option in children who require a low-profile proximal anchor. The vertical expandable prosthetic titanium rib (VEPTR(®)) appears to be beneficial for patients with congenital scoliosis and fused ribs, and thoracic Insufficiency Syndrome. Children with medical comorbidities who may not tolerate repeated lengthenings should be considered for Shilla or Luque Trolley technique. Growth modulation using shape memory alloy staples or other tethers seem promising for mild curves, although more research is required to define their precise indications.