Curve progression following selective and nonselective spinal fusion for adolescent idiopathic scoliosis: are selective fusions stable?

PURPOSE: The purpose of this study is to compare postoperative outcomes between selective and non-selective fusions longitudinally over the first five postoperative years. METHODS: Patient parameters were retrieved from a multicenter, prospective, database. Patients with Lenke 1-6, B and C deformities were included. Patients were stratified into 2 groups: selective fusion (SF), if the last instrumented vertebra (LIV) was at or cranial to the lumbar apex, or non-selective fusion (NSF). Differences in coronal and sagittal radiographic outcomes were assessed with generalized linear models (GLMs) at 1-, 2- and 5- year postoperative outcomes. Five-year postoperative categorical radiographic outcomes, flexibility, scoliosis research society scores (SRS), and reoperation rates were compared between groups. Matched cohorts were created for subgroup analysis. RESULTS: 416 (SF:261, NF:155) patients, including 353 females were included in this study. The mean preoperative thoracic and lumbar Cobb angles were 57.3 ± 8.9 and 45.3 ± 8.0, respectively. GLMs demonstrated greater postoperative coronal deformity in the SF group (p < 0.01); however, the difference between groups did not change overtime (p > 0.05) indicating a relatively stable postoperative deformity correction. The SF group had a greater incidence of lumbar Cobb ≥ 26 degrees (p < 0.01). The NSF group demonstrated worse forward and lateral flexibility at 5-year postoperative outcome (p < 0.05). There was no difference in postoperative SRS scores between the SF and NSF groups. Reoperation rates were similar between groups. CONCLUSION: Selective fusion results in greater coronal plane deformity; however, this deformity does not progress significantly over time compared to non-selective fusion. Selective spinal fusion may be a beneficial option for a larger subset of patients than previously identified. LEVEL OF EVIDENCE: III.

Proximal foundation anchor variations and their correlation with unplanned return to the operating room (UPROR) in children with EOS treated with magnetically controlled growing rods (MCGR).

INTRODUCTION: The evolution of MCGR technique has led to modifications in the configuration of the proximal construct to decrease the incidence of implant-related complications (IRC) and revision surgeries. However, there is no data characterizing the performance of the most used configurations reducing the risk of complications. METHODS: 487 patients were identified from an international multicenter EOS database. INCLUSION CRITERIA: EOS patients, primary dual MCGR, complete radiographs, and minimum of 2-year follow-up. 76 patients had incomplete X-rays, 5 had apical fusions, and 18 had inconclusive complications, leaving 388 patients for review. A digital spine template was created to document UIV; number of levels; number, type, and location of anchors; as well as implant configuration. First available postoperative and latest follow-up radiographs were reviewed by two senior surgeons and two spine fellows. UPROR due to IRC was defined as any change in proximal anchors between the postoperative and final follow-up radiographs. RESULTS: The most common proximal construct configuration: UIV at T2 (50.0%) with 17.5% UPROR, followed by T3 (34.0%) with 12.1% UPROR; number of levels was three (57.1%) with 16.8% UPROR and two (26.0%) with 17.0% UPROR; number of proximal anchors was six (49.9%) with 14.1% UPROR and four (27.0%) with 18.3% UPROR. The most common anchors were all screws (42.0%) with 9.9% UPROR, and all hooks (26.4%) with 31.4% UPROR (P < 0.001). The construct with the lowest rate of UPROR was a UIV at T2, with six anchors (all screws) across three levels (42 cases), with 0% UPROR. Other construct combinations that yielded 0% UPROR rates were UIV of T3, six anchors (all screws) across three levels (25 cases), and a UIV of T3 with six anchors (screws and hooks) across three3 levels (9 cases). CONCLUSION: Proximal anchor configuration impacts the incidence of UPROR due to IRC in MCGR. UIV at T2 and T3 compared to T4, and the use of all screws or combination of screws and hooks compared to all hooks were associated with a lower UPROR rate. The most common construct configuration was T2 UIV, three levels, six anchors, and all screws. The use of a combination of six anchors (screws or screws and hooks) across three levels with a UIV at T2 or T3 was associated with a lower UPROR rate. Additional research is needed to further evaluate the variables contributing to configuration selection and their association with IRC.

The Utility of the Surgical Apgar Score in Assessing the Risk of Perioperative Complications Following Spinal Fusion Surgery for Pediatric Patients with Scoliosis and Cerebral Palsy.

STUDY DESIGN: Cohort study. OBJECTIVE: Validate the Surgical Apgar Score (SAS) as a means of predicting perioperative major complications occurring within 30 days after scoliosis surgery in pediatric patients with cerebral palsy (CP). SUMMARY OF BACKGROUND DATA: A patient's SAS, which is composed of three commonly recorded intraoperative variables, predicts postoperative complications after various types of spine surgery. This has not; however, been studied in pediatric patients with scoliosis and CP, a population that experiences a high incidence of complications after corrective spinal surgery. METHODS: Pediatric CP patients who underwent spinal correction surgery were included in this study. Patient background, surgical variables, and perioperative complications occurring within 30 days after surgery were collected. Patients were divided into 4 groups based on their SAS: SAS 0-4, SAS 5-6, SAS 7-8, SAS 9-10. The incidences of perioperative complications for each group were compared using a receiver operating characteristic analysis. Area under curve (AUC) is reported. RESULTS: A total of 111 patients met the inclusion criteria. There were no death cases. There were 44 (39.6%) perioperative major complications in 37 (33.3%) patients that occurred within 30 days after spine surgery. The most frequent perioperative complications were pulmonary issues (13.5%). The incidence of perioperative major complication in each SAS group was as follows: SAS 0-4; 51.6%, SAS 5-6; 30.2%, SAS 7-8; 18.5%, SAS 9-10; 0/0. When the SAS 7-8 group was set as the reference, there was no significant difference compared to SAS 5-6 (P=0.34), while the incidence rate was significantly increased in SAS 0-4 (P=0.02). The AUC was 0.65 (95% Confidence Interval: 0.54-0.75). CONCLUSIONS: Overall, there were 37 (33.3%) patients with CP who had a major complication within 30 days after spinal surgery. Lower SAS, with the 0-4 group being the cutoff, were associated with significantly higher complication rates than higher SAS groups.

Representation and Race in Adolescent Idiopathic Scoliosis Research: Disparities in Curve Magnitude and Follow-Up.

STUDY DESIGN: Prospective Cohort Study. OBJECTIVE: The present study aims to determine if the racial representation of patients enrolled in a large prospective scoliosis registry is reflective of the general United States population. Further, we studied whether there was an association between race, pre-operative parameters, outcomes and loss to follow-up. METHODS: Prospectively collected data for patients who underwent spinal fusion for adolescent idiopathic scoliosis (AIS) was reviewed, including self-reported race/ethnicity. The U.S. pediatric population and U.S. patients enrolled in the prospective registry were compared. The data obtained was analyzed for variations between races, for pre-operative variables and follow-up. RESULTS: Of the 2210 included patients in the registry 66% of patients reported as White, while 52% of the 2018 U.S. pediatric population reported as White. 15% of the registry reported as Hispanic/Latino compared to 22% of the U.S. pediatric population, 13% Black compared to 14% of the U.S. pediatric population, and 4% Asian compared to 5% of the U.S. pediatric population. Asian and White patients had statistically significant higher 2-year follow-up in all but one of six enrollment sites (P < 0.001). Native American, Other, and Hispanic/Latino patients had the highest BMIs. Native American and Black patients had the highest pre-op thoracic Cobb angles. Pre-op ages of Black, Hispanic, and Native American patients were statistically lower (P < 0.01). CONCLUSION: This study demonstrates the association between race and patient follow-up and pre-operative factors in patients who underwent surgery for AIS. Black, Native American, and Hispanic populations were underrepresented both at pre-op and follow-up when compared to their relative proportion in the U.S. pediatric population.

Growth modulation response in vertebral body tethering depends primarily on magnitude of concave vertebral body growth.

PURPOSE: There is variability in clinical outcomes with vertebral body tethering (VBT) partly due to a limited understanding of the growth modulation (GM) response. We used the largest sample of patients with 3D spine reconstructions to characterize the vertebra and disc morphologic changes that accompany growth modulation during the first two years following VBT. METHODS: A multicenter registry was used to identify idiopathic scoliosis patients who underwent VBT with 2 years of follow-up. Calibrated biplanar X-rays obtained at longitudinal timepoints underwent 3D reconstruction to obtain precision morphological measurements. GM was defined as change in instrumented coronal angulation from post-op to 2-years. RESULTS: Fifty patients (mean age: 12.5 ± 1.3yrs) were analyzed over a mean of 27.7 months. GM was positively correlated with concave vertebra height growth (r = 0.57, p < 0.001), 3D spine length growth (r = 0.36, p = 0.008), and decreased convex disc height (r = - 0.42, p = 0.002). High modulators (patients experiencing GM > 10°) experienced an additional 1.6 mm (229% increase) of mean concave vertebra growth during study period compared to the Poor Modulators (GM < - 10°) group, (2.3 vs. 0.7 mm, p = 0.039), while convex vertebra height growth was similar (1.3 vs. 1.4 mm, p = 0.91). CONCLUSION: When successful, VBT enables asymmetric vertebra body growth, leading to continued postoperative coronal angulation correction (GM). A strong GM response is correlated with concave vertebral body height growth and overall instrumented spine growth. A poor GM response is associated with an increase in convex disc height (suspected tether rupture). Future studies will investigate the patient and technique-specific factors that influence increased growth remodeling.

Severe (>100 Degrees) Thoracic Adolescent Idiopathic Scoliosis - A Comparison of Surgical Approaches.

STUDY DESIGN: Retrospective. OBJECTIVE: Severe curves >100° in adolescent idiopathic scoliosis (AIS) are rare and require careful operative planning. The aim of this study was to assess baseline, perioperative, and 2-year differences between anterior release with posterior instrumentation (AP), posterior instrumentation with posterior column osteotomies (P), and posterior instrumentation with 3-column vertebral osteotomies (VCR). METHODS: Two scoliosis datasets were queried for primary cases of severe thoracic AIS (≥100°) with 2-year follow-up. Pre- and 2-year postoperative radiographic measures (2D and estimated 3D kyphosis), clinical measurements, and SRS-22 outcomes were compared between three approaches. RESULTS: Sixty-one patients were included: 16 AP (26%), 38 P (62%), 7 VCR (11%). Average age was 14.4 ± 2.0 years; 75.4% were female. Preoperative thoracic curve magnitude (AP: 112°, P: 115°, VCR: 126°, P = 0.09) and T5-T12 kyphosis (AP: 38°, P: 59°, VCR: 70°, P = 0.057) were similar between groups. Estimated 3D kyphosis was less in AP vs P (-12° vs 4°, P = 0.016). Main thoracic curves corrected to 36° in AP vs 49° and 48° for P and VCR, respectively (P = 0.02). Change in estimated 3D kyphosis was greater in AP vs P and VCR (34° vs 13°, P = 0.009; 34° vs 7°, P = 0.046). One incomplete spinal cord injury had residual deficits (P; 1/61, 1.6%). All SRS-22 domains improved postoperatively. CONCLUSION: All approaches obtained satisfactory coronal and sagittal correction, but AP had smaller residual coronal deformity and greater kyphosis restoration than the other approaches. This information may help inform the decision of whether to include an anterior release for large thoracic AIS curves.

Disparities in Indications and Outcomes Reporting for Spinal Column Shortening for Tethered Cord Syndrome: The Need for a Standardized Approach.

STUDY DESIGN: Systematic review. OBJECTIVE: To identify commonly reported indications and outcomes in spinal column shortening (SCS) procedures. BACKGROUND: SCS is a surgical procedure used in patients with tethered cord syndrome-characterized by abnormal attachment of neural components to surrounding tissues-to shorten the vertebral column, release tension on the spinal cord/neural elements, and alleviate associated symptoms. PATIENTS AND METHODS: PubMed and EMBASE searches captured SCS literature published between 1950 and 2023. Prospective/retrospective cohort studies and case series were included without age limit or required follow-up period. Review articles without new patient presentations, meta-analyses, systematic reviews, conference abstracts, and letters were excluded. Studies included adult and pediatric patients. RESULTS: The 29 identified studies represented 278 patients (aged 5-76 yr). In 24.1% of studies, patients underwent primary tethered cord syndrome intervention through SCS. In 41.4% of studies, patients underwent SCS after failed previous primary detethering (24.1% of studies were mixed and 10.3% were unspecified). The most commonly reported nongenitourinary/bowel surgical indications were back pain (55.2%), lower-extremity pain (48.3%), lower-extremity weakness (48.3%), lower-extremity numbness (34.5%), and lower-extremity motor dysfunction (34.5%). Genitourinary/bowel symptoms were most often described as nonspecific bladder dysfunction (58.6%), bladder incontinence (34.5%), and bowel dysfunction (31.0%). After SCS, nongenitourinary/bowel outcomes included lower-extremity pain (44.8%), back pain (31.0%), and lower-extremity sensory and motor function (both 31.0%). Bladder dysfunction (79.3%), bowel dysfunction (34.5%), and bladder incontinence (13.8%) were commonly reported genitourinary/bowel outcomes. In total, 40 presenting surgical indication categories and 33 unique outcome measures were reported across studies. Seventeen of the 278 patients (6.1%) experienced a complication. CONCLUSION: The SCS surgical literature displays variability in operative indications and postoperative outcomes. The lack of common reporting mechanisms impedes higher-level analysis. A standardized outcomes measurement tool, encompassing both patient-reported outcome measures and objective metrics, is necessary. LEVEL OF EVIDENCE: Level IV.

Three-dimensional vertebral shape changes confirm growth modulation after anterior vertebral body tethering for idiopathic scoliosis.

PURPOSE: To evaluate three-dimensional (3D) vertebra and disk shape changes over 2 years following anterior vertebral body tether (AVBT) placement in patients with idiopathic scoliosis (IS). METHODS: Patients with right thoracic IS treated with AVBT were retrospectively evaluated. 3D reconstructions were created from biplanar radiographs. Vertebral body and disk height (anterior, posterior, left and right) and shape (wedging angle) were recorded over the three apical segments in the local vertebral reference planes. Changes in height and wedging were measured through 2 years postoperatively. Change in patient height was correlated with changes in the spine dimensions. RESULTS: Forty-nine patients (Risser 0-3, Sanders 2-4) were included. The mean age was 12.2 ± 1.4 years (range 8-14). The mean coronal curve was 51 ± 10° preoperatively, 31 ± 9° at first postoperative time point and 27 ± 11° at 2-year follow-up (p < 0.001). The mean patient height increased 8 cm by 2 years (p < 0.001). The left side of the spine (vertebra + disc) grew in height by 2.2 mm/level versus 0.7 mm/level on the right side (p < 0.001). This differential growth was composed of 0.5 mm/vertebral level and 1.0 mm/disk level. Evaluation of the change in disk heights showed significantly decreased height anteriorly (- 0.4 mm), posteriorly (- 0.3 mm) and on the right (- 0.5 mm) from FE to 2 years. Coronal wedging reduced 2.3°/level with 1.1°/vertebral level change and 1.2°/disk level. There was no differential growth in the sagittal plane (anterior/posterior height). Patient height change moderately correlated with 3D measures of vertebra + disk shape changes. CONCLUSIONS: Three-dimensional analysis confirms AVBT in skeletally immature patients results in asymmetric growth of the apical spine segments. The left (untethered) side length increased more than 3 × than the right (tethered) side length with differential effects observed within the vertebral bodies and disks, each correlating with overall patient height change.

Intrawound Vancomycin Powder Reduces Delayed Deep Surgical Site Infections Following Posterior Spinal Fusion for Adolescent Idiopathic Scoliosis.

STUDY DESIGN: Retrospective. OBJECTIVE: Evaluate whether the use of vancomycin powder (VP) placed in the surgical site before wound closure prevents delayed deep surgical site infections (DDI). SUMMARY OF BACKGROUND DATA: DDI after posterior spinal fusion (PSF) in adolescent idiopathic scoliosis (AIS) patients remains a significant and major complication. The use of VP to prevent acute surgical site infection has been reported, but the impact on DDI is unknown. MATERIALS AND METHODS: AIS patients treated over the past 20 years with PSF or instrumentation from a large multicenter registry were reviewed. Patients were divided into two groups: intraoperative vancomycin powder placed in the wound (VP) or no antibiotics placed in the wound (NVP). DDI was defined as an infection that occurred >90 days after surgery and required surgical intervention in the operating room. Patients who developed a DDI had secondary verification of VP use or not. χ 2 and Kaplan-Meier (K-M) survivorship analyses were used to compare demographics and the incident rate of DDI between groups. RESULTS: Totally, 4145 cases met the inclusion criteria for this study. A total of 43 DDI cases were identified (1.0%). The incidence of DDI for the VP group was 0.2% (4/2111), and 1.9% (39/2034) in the NVP group ( P <0.001). Given the difference in follow-up for the two groups, a cumulative survival and Kaplan-Meier analysis revealed the VP group had significantly better "survival" (no DDI) than the NVP group ( P <0.001). CONCLUSION: DDIs are significant adverse events that can greatly complicate patient recovery after PSF for AIS, including rehospitalization. This study found that patients who received VP intraoperatively were 10 times less likely to develop a DDI than those who did not receive VP. Although other advances and changes in surgical techniques may contribute to the significant decrease in infections found in the more recent VP cohort, VP should be considered as a prophylactic measure. LEVEL OF EVIDENCE: 4.

Scoliosis Research Society-22r and Ceiling Effects: Limited Capabilities for Precision-Medicine with Adolescent Idiopathic Scoliosis.

STUDY DESIGN: Retrospective registry analysis. OBJECTIVE: To examine predictions of individual Scoliosis Research Society-22r (SRS-22r) questions one year after surgery for adolescent idiopathic scoliosis (AIS). SUMMARY OF BACKGROUND DATA: A precision-medicine approach to AIS surgery will inform patients of the likelihood of achieving particular results from surgery, specifically individual responses to the SRS-22r questionnaire. METHODS: A multi-center AIS registry was queried for surgical AIS patients treated between 2002-2020. Preoperative data collected included standard demographic data, deformity descriptive data, and SRS-22r scores. Postoperative 1yr SRS-22r scores were modeled using ordinal logistic regression. . The highest probability was the most likely response. Model performance was examined by c-statistics, where c>.8 was considered excellent. Ceiling effects were measured by the proportion of patients reporting "5" to each question. RESULTS: 3251 patients contributed data to the study; mean age 14.4 (±2.2) yrs, female 2631 (81%), major thoracic coronal curve 53°, mean lumbar 41°. C-statistic values ranged from .6 (poor) to .8 (excellent) evidence of varied predictive capabilities. Q17 ("days off work/school", c = .84, ceiling achieved 75%) and Q15 ("financial difficulties", c = .86, ceiling achieved 82%) had the greatest predictive capabilities while Q11 ("pain medication", c=.73, ceiling achieved 67%), Q10 ("appearance", c=.72, ceiling achieved 35%), and Q19 ("attractive", c=.69, ceiling achieved 37%) performed poorly. CONCLUSION: Prediction of individual SRS-22r item responses perhaps most germane to AIS treatment was poor. Prediction of less relevant outcomes, where ceiling effects are present, was greater as the models chose "5" for all responses. These ceiling effects may limit discrimination and hamper efforts at personalized outcome predictions. LEVEL OF EVIDENCE: 3.

Vertebral body tethering for Lenke 1A curves: the lumbar modifier predicts less optimal outcomes.

INTRODUCTION: The addition of the L4 "AR" and "AL" lumbar modifier for Lenke 1A idiopathic scoliosis (IS) has been shown to direct treatment in posterior spinal fusion; however, its utility in vertebral body tethering (VBT) has yet to be evaluated. METHODS: A review of a prospective, multicenter database for VBT in IS was performed for patients with Lenke 1A deformities and a minimum of 2 years follow-up. Patients were categorized by their lumbar modifier (AR vs AL). Less optimal VBT outcome (LOVO) was defined as a final coronal curve > 35°, lumbar adding-on, or revision surgery for deformity progression or adding-on. RESULTS: Ninety-nine patients met inclusion criteria (81% female, mean 12.6 years), with 55.6% being AL curves. Overall, there were 23 instances of tether breakage (23.3%) and 20 instances of LOVO (20.2%). There was a higher rate of LOVO in AR curves (31.8% vs 10.9%, P = 0.01). Patients with LOVO had greater preoperative deformity, greater apical translation, larger coronal deformity on first erect radiographs, and less coronal deformity correction. Failure to correct the deformity < 30° on first erect was associated with LOVO, as was LIV selection short of the last touch vertebra (TV). Independent risk factors for LOVO included AR curves (OR 3.4; P = 0.04) and first erect curve magnitudes > 30 degrees (OR 6.0; P = 0.002). DISCUSSION: There is a 20.2% rate of less optimal VBT following VBT for Lenke 1A curves. AR curves are independently predictive of less optimal outcomes following VBT and require close attention to LIV selection. Surgeons should consider achieving an initial coronal correction < 30 degrees and extending the LIV to at least the TV to minimize the risk of LOVO.

Prospectively Collected Comparison of Outcomes Between Surgically and Conservatively Treated Patients With Adolescent Idiopathic Scoliosis.

STUDY DESIGN: Retrospective review of a prospectively collected multicenter registry. OBJECTIVE: To evaluate health-related quality of life (HRQOL) measures in an operative cohort of patients (OP) and compare them with a matched nonoperative cohort (NON). SUMMARY OF BACKGROUND DATA: Historically, the surgical outcomes of adolescent idiopathic scoliosis (AIS) have been radiographically evaluated. However, the importance of HRQOL measures and their impact on surgical outcomes are increasingly being understood. MATERIALS AND METHODS: We identified 90 NON patients with curves in the operative range who were observed for at least two years. These patients were matched with an OP cohort of 689 patients. All patients completed the Scoliosis Research Society-22 (SRS-22) questionnaire at the initial evaluation and at a minimum of two-year follow-up. Subgroup comparisons were based on curve type: primary thoracic (Th), primary thoracolumbar/lumbar (TL/L), and double major (DM) curves. RESULTS: The preoperative major curves in the Th, TL/L, and DM OP subgroups averaged 50.4°, 45.4°, and 51.5°, respectively, and 49.4°, 43.7°, and 48.9° in the NON cohort ( P >0.05). At two years postoperatively, the major curve in the Th, TL/L, and DM OP subgroups improved to 19.0°, 19.2°, and 19.3°, respectively, compared with the progression to 51.3°, 44.5°, and 49.7° in the NON group at two-year follow-up ( P <0.05). The SRS-22 self-image, mental health, satisfaction, and total scores at the two-year follow-up were significantly better in all OP subgroups ( P <0.001) but remained largely unchanged in the NON group. A significant percentage of patients ( P <0.001) in the OP cohort reported better SRS-22 scores at the two-year follow-up in the self-image, mental health, and satisfaction domains than the NON group at two years. CONCLUSIONS: Surgically treated patients with AIS have improved HRQOL outcomes in several domains compared with age-matched and curve magnitude-matched nonoperatively treated patients at two-year follow-up.

Depression Screening in Pediatric Orthopedic Surgery Clinics and Identifying Patients At-Risk.

BACKGROUND: Up to 25% of youth experience a depressive episode by 18 years of age, leading the US Preventive Services Task Force to recommend depression screening within this population. This study aimed to understand the prevalence of depression identified within pediatric orthopedic clinics compared with primary care clinics after the implementation of a screening program and present data on the prevalence of moderate-severe depression across specific pediatric orthopedic clinics, characterizing and identifying specific populations at higher risk. METHODS: A retrospective review was performed to identify all patients screened using the 2-item and 9-item versions of the Patient Health Questionnaire (PHQ-2/PHQ-9) and the Columbia-Suicide Severity Rating Scale over a 2-year period (October 2018 to January 2021) within pediatric primary care and orthopaedic clinics. Demographic and clinical characteristics were collected. Statistical analysis was performed to compare scores between orthopedic and primary care clinics, as well as between the different pediatric orthopedic subspecialties and included χ 2 test, ANOVA, and logistic regression. RESULTS: There were 32,787 unique adolescent patients screened in primary care clinics, with an additional 14,078 unique adolescent patients screened in orthopaedic clinics, leading to a 30% increase in the overall number of patients receiving depression screening. 5.2% of patients in primary care pediatric clinics screened positive for moderate-severe depression versus 2.0% in pediatric orthopaedic clinics ( P <0.001). 2.7% of primary care patients were at risk of self-harm compared with 0.8% of orthopedic patients ( P <0.001). Within orthopaedic subspecialty clinics, the spine patients were at the highest risk of moderate-severe depression (3.5%), significantly higher than both the sports (1.4%, P =0.006) and patients with acute fracture (1.3%, P <0.001). CONCLUSIONS: This study demonstrates the high incidence of patients screening positive for depression in pediatric and adolescent orthopaedic clinics. By identifying high-risk clinics and patient groups, health care systems can apply a more practical approach and appropriately deploy behavioral health specialists for timely counseling and treatment discussions. LEVEL OF EVIDENCE: Level-III.

3D analysis of the preoperative deformity in AIS can be used to guide surgical treatment decisions for selective thoracic fusion.

PURPOSE: To identify 3D measures of scoliosis from preoperative imaging that are associated with optimal radiographic outcomes after selective thoracic fusion (STF) for adolescent idiopathic scoliosis (AIS). METHODS: Subjects with primary thoracic curves (Lenke 1-4, B or C modifiers) fused selectively (L1 or above) who had preoperative 3D reconstructions and minimum 2 years of follow-up were included. An optimal outcome at 2 years was defined as having 4 of 5 parameters previously defined in the literature: (1) lumbar curve < 26º, (2) deformity flexibility quotient < 4, (3) C7-CSVL < 2 cm, (4) lumbar prominence < 5º and (5) trunk shift < 1.5 cm. Univariate and CART analyses were performed to identify preoperative variables associated with achieving an optimal outcome 2 years postoperatively. RESULTS: Ninety-nine (88F, 11 M) patients met inclusion. Mean age was 15 ± 2 years. Fifty-one subjects (52%) had an optimal outcome. Seven preoperative deformity measures representing smaller thoracolumbar/lumbar deformity in the optimal group were found to be significant on univariate analysis. CART analysis identified the following variables associated with optimal outcomes: difference in apical rotation > 30° = 27% optimal outcomes, difference in apical rotation ≤ 30° and coronal vertebral wedging of lumbar apex > 3° = 46% optimal outcomes, and difference in apical rotation ≤ 30° and coronal vertebral wedging of lumbar apex ≤ 3° = 80% optimal outcomes (p < 0.05). CONCLUSION: Optimal outcomes after STF were associated with a preoperative difference in apical vertebral rotation in the axial plane less than 30° between thoracic and lumbar curves as well as coronal plane vertebral wedging of the lumbar apical vertebra less than 3°.

Incidence of Tether Breakage in Anterior Vertebral Body Tethering.

BACKGROUND: Thoracic anterior vertebral body tethering (TAVBT) is an emerging treatment for adolescent idiopathic scoliosis. Tether breakage is a known complication of TAVBT with incompletely known incidence. We aim to define the incidence of tether breakage in patients with adolescent idiopathic scoliosis who undergo TAVBT. The incidence of tether breakage in TAVBT is hypothesized to be high and increase with time postoperatively. METHODS: All patients with right-sided, thoracic curves who underwent TAVBT with at least 2 and up to 3 years of radiographic follow-up were included. Tether breakage between 2 vertebrae was defined a priori as any increase in adjacent screw angle >5 degrees from the minimum over the follow-up period. The presence and timing of tether breakage were noted for each patient. A Kaplan-Meier survival analysis was performed to calculate expected tether breakage up to 36 months. χ 2 analysis was performed to examine the relationship between tether breakage and reoperations. Independent t test was used to compare the average final Cobb angle between cohorts. RESULTS: In total, 208 patients from 10 centers were included in our review. Radiographically identified tether breakage occurred in 75 patients (36%). The initial break occurred at or beyond 24 months in 66 patients (88%). Kaplan-Meier survival analysis estimated the cumulative rate of expected tether breakage to be 19% at 24 months, increasing to 50% at 36 months. Twenty-one patients (28%) with a radiographically identified tether breakage went on to require reoperation, with 9 patients (12%) requiring conversion to posterior spinal fusion. Patients with a radiographically identified tether breakage went on to require conversion to posterior spinal fusion more often than those patients without identified tether breakage (12% vs. 2%; P =0.004). The average major coronal curve angle at final follow-up was significantly larger for patients with radiographically identified tether breakage than for those without tether breakage (31 deg±12 deg vs. 26 deg±12 deg; P =0.002). CONCLUSIONS: The incidence of tether breakage in TAVBT is high, and it is expected to occur in 50% of patients by 36 months postoperatively. LEVEL OF EVIDENCE: Level IV.

Breaking the Rules in Three Dimensions: What to Expect After a Thoracic-only Fusion With Structural Thoracic and Thoracolumbar Curves.

OBJECTIVE: Despite guidelines to fuse both thoracic and thoracolumbar/lumbar (TH/L) curves in patients with structural curves in both regions, a thoracic-only fusion allows preservation of lumbar motion segments. The purpose of this study was to assess the 2-year postoperative three-dimensional (3D) radiographic and clinical outcomes of patients with double or triple major (thoracic curves >TH/L curves) structural curves who underwent a thoracic-only fusion. METHODS: A prospective adolescent idiopathic scoliosis registry was queried for double or triple major curves undergoing thoracic-only posterior fusion and a minimum 2-year follow-up. 3D reconstructions were generated from bi-planar radiographs. Paired sample t tests were used to assess differences in the coronal, sagittal, and axial planes pre and postoperatively, as well as Scoliosis Research Society Questionnaire-22 scores. Pearson correlations were utilized to identify variables related to spontaneous lumbar derotation. RESULTS: Twenty-two patients met the inclusion criteria. Both thoracic [61 ± 10 degrees to 20 ± 9 degrees ( P < 0.001)] and lumbar curves [41 ± 7 degrees to 22±7 degrees ( P < 0.001)] had significant coronal improvement and T5 to T12 kyphosis improved from 7 ± 14 degrees to 23 ± 8 degrees ( P < 0.001). The thoracic apical translation was significantly improved postoperatively (4.7 ± 1.5 to 0.5 ± 1 cm, P < 0.001), but the lumbar apical translation was unchanged (-1.7 ± 0.6 to -1.7±0.8 cm, P = 0.94). Scoliosis Research Society Questionnaire-22 scores significantly improved by 2 years postoperative. CONCLUSIONS: Unlike the 3D correction observed in nonstructural TH/L curves after thoracic-only fusion, patients with double or triple major curves demonstrated only spontaneous coronal correction of the lumbar curve, whereas the sagittal and axial planes were not significantly improved. These radiographic parameters did not negatively affect subjective or clinical outcomes at minimum 2-year follow-up. LEVEL OF EVIDENCE: Level IV-therapeutic.

Non-Fusion Versus Fusion Surgery in Pediatric Idiopathic Scoliosis: What Trade-Offs in Outcomes Are Acceptable for the Patient and Family?

BACKGROUND: Vertebral body tethering and other non-fusion techniques for the treatment of pediatric idiopathic scoliosis are increasing in popularity. There is limited physician consensus on this topic as the result of a paucity of published data regarding which patients most benefit from non-fusion strategies. Thus, much of the decision-making is left to patients and parents, who must select a treatment based on their goals and values and the information available from health-care providers, the internet, and social media. We sought to understand patient and family preferences regarding the attributes of fusion versus non-fusion surgery that drive these choices. METHODS: Patients and families were recruited from 7 pediatric spine centers and were asked to complete a survey-based choice experiment that had been jointly developed with the U.S. Food and Drug Administration (FDA) to evaluate patient preferences. Choices between experimentally designed alternatives were analyzed to estimate the relative importance of outcomes and requirements associated with the choice options (attributes). The attributes included appearance, confidence in the planned correction, spinal motion, device failure, reoperation, and recovery period. The inclusion criteria were (1) an age of 10 to 21 years and (2) a diagnosis of adolescent idiopathic scoliosis in patients who were considering, or who had already undergone, treatment with fusion or non-fusion surgery. Preference weights were estimated from the expected changes in choice given changes in the attributes. RESULTS: A total of 344 respondents (124 patients, 92 parents, and 128 parent/patient dyads) completed the survey. One hundred and seventy-three patients were enrolled prior to surgery, and 171 were enrolled after surgery. Appearance and motion were found to be the most important drivers of choice. For the entire cohort, fusion was preferred over non-fusion. For patients who were considering surgery, the most important attributes were preservation of spinal motion and appearance. CONCLUSIONS: Patients and families seeking treatment for idiopathic scoliosis value appearance and preservation of spinal motion and, to a lesser extent, reoperation rates when considering fusion versus non-fusion surgery.

Intraoperative neuromonitoring predicts postoperative deficits in severe pediatric spinal deformity patients.

PURPOSE: To evaluate intraoperative monitoring (IOM) alerts and neurologic deficits during severe pediatric spinal deformity surgery. METHODS: Patients with a minimum Cobb angle of 100° in any plane or a scheduled vertebral column resection (VCR) with minimum 2-year follow-up were prospectively evaluated (n = 243). Preoperative, immediate postoperative, and 2-year postoperative neurologic status were reported. Radiographic data included preoperative and 2-year postoperative coronal and sagittal Cobb angles and deformity angular ratios (DAR). IOM alert type and triggering event were recorded. SRS-22r scores were collected preoperatively and 2-years postoperatively. RESULTS: IOM alerts occurred in 37% of procedures with three-column osteotomy (n = 36) and correction maneuver (n = 32) as most common triggering events. Patients with IOM alerts had greater maximum kyphosis (101.4° vs. 87.5°) and sagittal DAR (16.8 vs. 12.7) (p < 0.01). Multivariate regression demonstrated that sagittal DAR independently predicted IOM alerts (OR 1.05, 95% CI 1.02-1.08) with moderate sensitivity (60.2%) and specificity (64.8%) using a threshold value of 14.3 (p < 0.01). IOM alerts occurred more frequently in procedures with new postoperative neurologic deficits (17/24), and alerts with both SSEP and TCeMEP signals were associated with new postoperative deficits (p < 0.01). Most patients with new deficits experienced resolution at 2 years (16/20) and had equivalent postoperative SRS-22r scores. However, patients with persistent deficits had worse SRS-22r total score (3.8 vs. 4.2), self-image subscore (3.5 vs. 4.1), and function subscore (3.8 vs. 4.3) (p ≤ 0.04). CONCLUSION: Multimodal IOM alerts are associated with sagittal kyphosis, and predict postoperative neurologic deficits. Most patients with new deficits experience resolution of their symptoms and have equivalent 2-year outcomes. LEVEL OF EVIDENCE: II.

From PHQ-2 to SRS-22: how a depression screening tool relates to SRS scores in patients with adolescent idiopathic scoliosis.

PURPOSE: The aim of our study was to determine the relationship between Patient Health Questionnaire (PHQ) scores-a simple, validated depression screening tool-and Scoliosis Research Society (SRS)-22 questionnaire scores in patients with idiopathic scoliosis (IS). METHODS: IS patients screened for depression with the PHQ-2 who completed the SRS-22 over a 2-year period were reviewed. If PHQ-2 scores were positive (> 3), the more comprehensive PHQ-9 was administered. Median SRS-22 scores between positive and negative PHQ screens were compared. Nonparametric correlation between PHQ and SRS-22 Mental Health (MH) domain was performed. The ability of the MH domain to discriminate between patients with positive versus negative screens and patients with moderate-severe depression risk versus no-mild risk was evaluated with ROC analysis. RESULTS: 521 patients were included. Patients with + PHQ-2 screens had significantly lower total and individual domain SRS scores, especially within the MH domain (4.0 vs. 3.2). For those with moderate-severe depression risk, total and individual domain scores were also significantly lower (MH domain, 4.0 vs. 3.0, p < 0.05). A weak, but significant correlation was observed between the PHQ and MH domain scores (rho = 0.32, p < 0.001). A cut-off of ≥ 3.6 on the MH domain demonstrated sensitivity of 0.75 and specificity of 0.86 for identifying patients at no-mild risk for depression. CONCLUSION: Recognizing mental health conditions is critical to successful IS treatment as psychosocial conditions can negatively affect treatment outcomes. IS patients scoring < 3.6 on the SRS-22 MH domain should be considered for depression screening due to an increased risk of moderate-severe depression.

BrAIST-Calc: Prediction of Individualized Benefit From Bracing for Adolescent Idiopathic Scoliosis.

STUDY DESIGN: Prospective multicenter study data were used for model derivation and externally validated using retrospective cohort data. OBJECTIVE: Derive and validate a prognostic model of benefit from bracing for adolescent idiopathic scoliosis (AIS). SUMMARY OF BACKGROUND DATA: The Bracing in Adolescent Idiopathic Scoliosis Trial (BrAIST) demonstrated the superiority of bracing over observation to prevent curve progression to the surgical threshold; 42% of untreated subjects had a good outcome, and 28% progressed to the surgical threshold despite bracing, likely due to poor adherence. To avoid over-treatment and to promote patient goal setting and adherence, bracing decisions (who and how much) should be based on physician and patient discussions informed by individual-level data from high-quality predictive models. MATERIALS AND METHODS: Logistic regression was used to predict curve progression to <45° at skeletal maturity (good prognosis) in 269 BrAIST subjects who were observed or braced. Predictors included age, sex, body mass index, Risser stage, Cobb angle, curve pattern, and treatment characteristics (hours of brace wear and in-brace correction). Internal and external validity were evaluated using jackknifed samples of the BrAIST data set and an independent cohort (n=299) through estimates of discrimination and calibration. RESULTS: The final model included age, sex, body mass index, Risser stage, Cobb angle, and hours of brace wear per day. The model demonstrated strong discrimination ( c -statistics 0.83-0.87) and calibration in all data sets. Classifying patients as low risk (high probability of a good prognosis) at the probability cut point of 70% resulted in a specificity of 92% and a positive predictive value of 89%. CONCLUSION: This externally validated model can be used by clinicians and families to make informed, individualized decisions about when and how much to brace to avoid progression to surgery. If widely adopted, this model could decrease overbracing of AIS, improve adherence, and, most importantly, decrease the likelihood of spinal fusion in this population.