Faculty Bibliography

BACKGROUND CONTEXT: Prior adolescent idiopathic scoliosis (AIS) literature has demonstrated that patient satisfaction correlated weakly with individual SRS-22r domains and did not correlate with specific radiographic parameters. PURPOSE: The purpose of this study is to demonstrate the effect of residual deformity on patient satisfaction. We hypothesize that in patients with AIS, residual deformity maybe associated with worse satisfaction. STUDY DESIGN/SETTING: Retrospective analysis of a prospective AIS registry. PATIENT SAMPLE: A total of 1,229 Lenke 1 and 2 AIS patients with available radiographic data and SRS scores at the 2-year follow-up were included. OUTCOME MEASURES: Patient satisfaction using the SRS-22r satisfaction domain, categorized into 2 groups: Complete satisfaction (5/5) and incomplete satisfaction/dissatisfaction (<5).
METHOD(S): A total of 1,229 Lenke 1 and 2 AIS patients with available radiographic data and SRS scores at the 2-year follow-up were included. A score of 5 on the SRS-22r satisfaction domain at 2 years was considered "complete satisfaction," and anything below a score of 5 was considered "incomplete satisfaction/dissatisfaction." Radiographic parameters that were 2 standard deviations below the mean were deemed to have a "residual deformity." Univariate and binary logistic analyses were performed to assess the association of residual deformity with patient satisfaction.
RESULT(S): At the 2-year follow-up, 689 (60%) patients reported complete satisfaction, while 455 (40%) reported incomplete satisfaction/dissatisfaction. Radiographic factors associated with incomplete satisfaction/dissatisfaction were: residual trunk shift (OR 3.32, p=0.001) and residual major curve (OR 1.7, p=0.036). Patients with residual trunk shift and major curve also had worse SRS-22r self-image domain scores at the 2-year follow-up. Residual differences in shoulder height (p=0.534), T1 tilt angle (p=0.062), Apex to CSVL distance (p=0.969), and percent correction of the major curve (p=0.102) did not reach statistical significance for predicting incomplete satisfaction/dissatisfaction.
CONCLUSION(S): Residual curve (>34) and truncal shift (>2.2cm) impact patient satisfaction after surgery for AIS. These factors ought to be taken into account during surgical planning. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Prior literature in patients with adult spine deformity has found that poor mental health at baseline is associated with worse postoperative outcomes. PURPOSE: The purpose of this study is to demonstrate that adolescent idiopathic scoliosis (AIS) patients with poor mental health at baseline can experience significant improvements with surgery. We hypothesize that in AIS, low SRS-22r mental health scores are largely due to the presence of deformity. The purpose of this study is determine if the correction of the deformity would potentially improve mental health scores. STUDY DESIGN/SETTING: Retrospective review of prospective AIS registry. PATIENT SAMPLE: Adolescents with idiopathic scoliosis. OUTCOME MEASURES: Mental health scores and percent of patients reaching minimum clinically important difference (MCID) at 2 years postoperative.
METHOD(S): A total of 1,532 (1,261 girls, 271 boys) with available baseline and 2-years follow-up SRS-22r scores were included. Patients with baseline mental health domain scores who were 1 standard deviation below the mean (< 3.3) were classified as "low mental health" score (LMH) group, and patients who were 1 standard deviation above the mean (> 4.7) were classified as "high mental health" score (HMH) group. The remaining patients were classified as "intermediate mental health" score (IMH). A minimal clinically important difference (MCID) of 0.6 was used for SRS-22r for analysis RESULTS: There were 247 patients in the LMH group, 1,015 in the MMH group, and 270 in the HMH group. Compared to baseline, all 3 groups demonstrated significant improvements in the overall SRS-22r scores at the 2-year follow-up: 0.8 +/-0.5 in the LMH group, 0.5 +/-0.4 in the IMH group, and 0.29 +/-0.35 in the HMH group (P<0.001 each). Further, at the 2-year follow-up, 72% of patients in the LMH group, 40% of patients in the IMH group, and 17% of patients in the HMH group reached MCID for SRS-22r. At the 2-year follow-up, there was no significant difference in the final SRS-22r score of the 3 groups.
CONCLUSION(S): In distinction from adult deformity patients, in the AIS population, alterations in normal body image may results in low mental health at baseline. These patients can experience significant benefit with surgery, and majority of these patients achieve MCID for the SRS-22r at the 2-year follow-up. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT: Surgical correction of adolescent idiopathic scoliosis is advocated for severe curves to preserve or improve pulmonary function, prevent progressive deformity and pain, and improve self-appearance. Restoration of sagittal and 3D alignment, in particular thoracic kyphosis (TK), has become increasingly emphasized in efforts to improve pulmonary function, thoracic volumes, provide improved sagittal balance, and prevent adjacent segment degeneration and deformity. PURPOSE: To study the effects of thoracic kyphosis restoration in AIS type 1 and 2 curves on postoperative thoracic volume and pulmonary function. STUDY DESIGN/SETTING: Retrospective review of prospective multicenter database. PATIENT SAMPLE: Thirty-nine AIS patients with Type 1 and 2 curves with 5Y postoperative stereo-radiographic data and pulmonary function tests (PFTs). OUTCOME MEASURES: Five-year spinal and rib cage measures and PFTs.
METHOD(S): A multicenter prospective registry of patients undergoing surgical correction of Type 1- and 2- AIS curves was queried for patients with 5-year postoperative visits including stereoradiographic assessment and PFTs. 3-dimensional (3D) radiographic analysis was performed to assess spinal alignment and chest wall dimensions at preoperative, first erect and 5 year postoperative time points. Variables were analyzed between time points with a one-way ANOVA and post-hoc Tukey analysis, and between variables with linear regression analysis.
RESULT(S): A total of 39 patients met the inclusion criteria (37F, age 14.4+/-2.2). 3D spine alignment analyses demonstrated significant reduction in pre-op to 1st erect upper thoracic (41.3degree to 11.6degree), mid-thoracic (48.6degree to 9.55degree) and lumbar Cobb angles (19.7degree to 8.9degree), an increase in TK:T2-12 (20.0degree to 39.8degree) and TK:T5-12 (9.8 to 28.2degree), and reduction in proximal and mid-thoracic apical vertebral rotation (9.5degree to 2.1degree) from preoperative to 1st erect postoperative (p<0.001 for all). 3D spinal alignment remained stable from 1st erect to 5 years (p>0.05 for all). 3D rib cage analysis demonstrated there was a small reduction in maximal depth (144 mm to 138 mm), maximum width (235 mm to 232 mm), and increase in thoracic height (220 mm to 230 mm, p<0.01 for all), but no significant change in rib cage volume (5136 to 5202 cm³ p=0.184). There was no correlation between change in coronal or sagittal alignment parameters and perioperative change in rib cage volume. From first erect to 5-year a significant increase in max depth (138 mm to 144 mm), width (232 mm to 242 mm), thoracic height (230 mm to 233 mm) and rib cage volume (5202 cm to 5912 cm, p<0.001 for all) occurred. Pulmonary function analysis showed significant improvement in FEV1 (2.73 to 2.98 L, p=0.003) and FVC (3.22 to 3.46 L, p=0.006) from preoperative to 5-year, however, TLC did not change (4.54 to 4.59 L, p=0.517). Percent predicted TLC was reduced (Pre:101.3% to 5Y:89.1%, p<0.001), however, % predicted FEV and FVC did not (89% to 86.4%, p=0.227 & 92.5% to 87.7%, p=0.10 respectively). PFTs at 5-year follow-up correlated most closely with rib cage volume at 5-year follow-up (FEV r=0.643, FVC r=0.800, TLC r=0.73, p<0.001).
CONCLUSION(S): While thoracic kyphosis increases, coronal Cobb and apical vertebral rotation decrease postoperatively, these do not directly influence chest wall volume. Chest wall volume continues to increase between from first erect to 5 years due to presumed growth, which corresponds with an improvement in FEV1 and FVC at 5 year follow-up. FDA DEVICE/DRUG STATUS: This abstract does not discuss or include any applicable devices or drugs.
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BACKGROUND CONTEXT/BACKGROUND:The minimal clinically important difference (MCID) is the smallest change in an outcomes instrument deemed relevant to a patient. MCID values proposed in spine research are limited by poor discriminative abilities to accurately classify patients as "improved" or "not improved." Furthermore, the MCID should not compare relative effectiveness between two groups of patients, though it is frequently used for this. The minimum detectable measurement difference (MDMD) is an alternative to the MCID in outcomes research. The MDMD must be greater than the MCID for the latter to be of value and the MDMD can compare change between groups. PURPOSE/OBJECTIVE:The purpose of this study was to determine the MDMD for the scoliosis research society-22r (SRS-22r) in adolescent idiopathic scoliosis (AIS) patients treated with surgery. STUDY DESIGN/METHODS:Retrospective cohort study from multi-center registry. PATIENT SAMPLE/METHODS:Patients treated surgically for AIS. OUTCOME MEASURES/METHODS:Self-reported SRS-22r. METHODS:An observational cohort of surgically treated AIS patients was queried for patients with complete baseline, 1-year, and 2-year SRS-22r data. The MDMD was calculated for SRS-22r domain and subscores. Effect size (ES) and standardized response mean were calculated to measure responsiveness of the SRS-22r to change. MDMD values were compared with MCID values. Research grants were received from DePuy Synthes Spine, EOS imaging, K2M, Medtronic, NuVasive, and Zimmer Biomet to Setting Scoliosis Straight Foundation. RESULTS:One thousand two hundred and eighty-one AIS patients (1,034 female, 247 male, mean age 14.6 years) were analyzed. MDMD values were between 0.23 and 0.31. SRS-Pain MDMD was 0.3, greater than the MCID of 0.2. SRS-Activity MDMD was 0.24, greater than the MCID of 0.08. SRS-self-image MDMD was 0.3, less than the MCID of 0.98. Sixty-four percent of those with baseline SRS-self-image>4.0 improved MDMD or more, whereas only 14% improved beyond the MCID. ES and standardized response mean were highest for subscore and self-image. CONCLUSIONS:The MDMD can compare the relevance of change in SRS-22r scores between groups of AIS patients. SRS-pain and SRS-activity MDMD values are greater than the MCID and should serve as the threshold for clinically relevant improvement. MDMD may help evaluate change in patients with baseline self-image>4.0.

BACKGROUND:Selective fusions of the structural curve remain a common treatment strategy for adolescent idiopathic scoliosis, yet long-term outcomes are not well-understood. The purpose of this study was to report 10-year prospective radiographic and patient-rated outcomes of selective fusions of the main thoracic (MT) or thoracolumbar/lumbar (TL/L) curve, with particular attention to the behavior of the uninstrumented, compensatory curve. METHODS:A prospectively collected multicenter database was used to identify patients who had been followed regularly for least 10 years after a selective MT or TL/L fusion for adolescent idiopathic scoliosis. Interval radiographs were evaluated for coronal and sagittal Cobb angles as well as overall coronal balance. Scores on the Scoliosis Research Society Questionnaire (SRS-24) were catalogued and evaluated. Radiographic outcomes and SRS-24 scores were compared between preoperative and postoperative time points using repeated-measures analysis of variance. Individual patient records were screened for recent curve progression of >5°, and these cases were methodically evaluated. RESULTS:Fifty-one patients with selective fusions (21 MT and 30 TL/L) for adolescent idiopathic scoliosis who had been followed for at least 10 years were identified. The instrumented MT and TL/L curves were corrected by an average of 51% and 60%, respectively, at 10 years. The uninstrumented, compensatory curves had gradual spontaneous correction that approached the magnitude of the fused curve at 5 years postoperatively, with the correction maintained at 10 years. This led to excellent coronal balance. A subgroup of patients had recent progression of the primary curve adjacent to the prior fusion or within the instrumented segments, resulting in a compensatory progression of the uninstrumented curve. On the whole, SRS scores did not decrease during follow-up, and no patient had secondary operations. CONCLUSIONS:Selective fusion of a primary thoracic or lumbar curve in properly selected patients with adolescent idiopathic scoliosis will result in spontaneous correction of the uninstrumented curve and a durable result for at least 10 years. LEVEL OF EVIDENCE/METHODS:Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

BACKGROUND:At academic medical centers, residents and fellows play an integral role as surgical first assistants in spinal deformity surgery. However, limited data exist on whether the experience level of the surgical assistant affects outcomes. METHODS:We conducted a multicenter, multisurgeon study comparing perioperative and postoperative outcomes after adolescent idiopathic scoliosis (AIS) surgery for the same 11 surgeons who performed cases that were assisted by residents compared with cases that were assisted by fellows. Blood loss, operative time, duration of hospitalization, complication rates, Scoliosis Research Society (SRS)-22 questionnaire scores, and radiographic outcomes were compared between the 2 groups. RESULTS:We evaluated outcomes for 347 surgical procedures; 118 cases were assisted by residents and 229 were assisted by fellows. Preoperative radiographic and demographic parameters were not different between the groups. The resident group had significantly more estimated blood loss than the fellow group (939 compared with 762 mL, p = 0.02). Otherwise, the perioperative characteristics were similar between the groups, including the volume of the autologous blood recovery system product that was transfused, the operative time, and the occurrence of intraoperative neuromonitoring changes. Postoperatively, the percentage correction of the Cobb angle, the number of levels that had been fused, the number of days until the discharge criteria had been met, and the rate of major complications were similar between the groups. At the 2-year follow-up, the overall and subdomain SRS-22 questionnaire scores were not different between the groups, except that patients in the resident-assisted group had slightly worse pain scores than those in the fellow-assisted group (4.3 compared with 4.5, p = 0.01). CONCLUSIONS:The first assistant's level of training did not affect clinical or radiographic outcomes following AIS surgery. LEVEL OF EVIDENCE/METHODS:Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

STUDY DESIGN/METHODS:Cost-utility analysis OBJECTIVE.: To compare the cost utility of operative versus nonoperative treatment of adolescent idiopathic scoliosis (AIS) and identity factors that influence cost-utility estimates. SUMMARY OF BACKGROUND DATA/BACKGROUND:AIS affects 1% to 3% of children aged 10 to 16 years. When the major coronal curve reaches 50°, operative treatment may be considered. The cost utility of operative treatment of AIS is unknown. METHODS:A decision-analysis model comparing operative versus nonoperative treatment was developed for a hypothetical 15-year-old skeletally mature girl with a 55° right thoracic (Lenke 1) curve. The AIS literature was reviewed to estimate the probability, health utility, and quality-adjusted life years (QALYs) for each event. For the conservative model, we assumed that operative treatment did not result directly in any QALYs gained, and the health utility in AIS patients was the same as the age-matched US population mean. Costs were inflation-adjusted at 3.22% per year to 2015 US dollars. Costs and benefits were discounted at 3%. Probabilistic sensitivity analysis was performed using mixed first-order and second-order Monte Carlo simulations. Incremental cost utility ratio (ICUR) and incremental net monetary benefit were calculated. One-way sensitivity analyses were performed by varying cost, probability, and QALY estimates. RESULTS:Operative treatment was favored in 98.5% of simulations, with a median ICUR of $20,600/QALY (95% confidence interval, $20,500-$21,900) below the societal willingness-to-pay threshold (WTPT) of $50,000/QALY. The median incremental net monetary benefit associated with operative treatment was $15,100 (95% confidence interval, $14,800-$15,700). Operative treatment produced net monetary benefit across various WTPTs. Factors that most affected the ICUR were net costs associated with uncomplicated operative treatment, undergoing surgery during adulthood, and development of pulmonary complications. CONCLUSION/CONCLUSIONS:Cost-utility analysis suggests that operative treatment of AIS is favored over nonoperative treatment and falls below the $50,000/QALY WTPT for patients with Lenke 1 curves. LEVEL OF EVIDENCE/METHODS:2.

The corresponding author regret that co-author name was incorrectly published as "Elias C. Papadopoulus" in the article. The correct name of the author should be displayed as "Elias C. Papadopoulos".

STUDY DESIGN/METHODS:Observational cohort study of prospective database registry. OBJECTIVE:To determine the incidence of neurological complications in AIS patients undergoing surgical treatment with PO. SUMMARY OF BACKGROUND DATA/BACKGROUND:Despite the widespread use of Ponte Osteotomies (PO) in adolescent idiopathic scoliosis (AIS) correction, outcomes and complications in patients treated with this technique have not been well characterized. METHODS:A multicenter prospective registry of patients undergoing surgical correction of AIS was queried at 2-year follow up for patient demographics, surgical data, deformity characteristics and peri-operative complications. A neurological complication was defined as perioperative nerve root or spinal cord injury as identified by the surgeon. Patients were divided into those that underwent peri-apical PO and those without, and further stratified by Lenke curve classification into 3 groups (I-types 1 & 2, II- types 3, 4, 6, and III-type 5). Patients with- and without neurological complications were compared with respect to baseline demographics, surgical variables, curve types, fusion construct types (screws vs. hybrid), curve magnitude (coronal and sagittal Cobb), apical vertebral translation, and coronal- deformity angular ratios (C-DAR). RESULTS:Of 2210 patients included in the study, 1611 underwent PO. Peri-operative neurological complications occurred in 7 patients, with 6 in the PO group (0.37%) and 1 in non-PO group (0.17%) though this was not a statistically significant risk factor for peri-operative neurological injury (p = 0.45). Neuromonitoring alerts were recorded in 168 patients (7.6%: 9.3% PO group; 4.2% no-PO group (p < 0.001). Multivariate logistic regression analysis found PO and curve magnitude to be independent risk factors for intra-operative neuromonitoring alerts (p < 0.01). CONCLUSIONS:PO and curve magnitude were independent risk factors for intra-operative neuromonitoring alerts in surgical AIS correction. The effect of Ponte osteotomy on neurological complications remains unknown due to the low incidence of these complications. LEVEL OF EVIDENCE/METHODS:3.