Clinical and radiological outcomes of gradual reduction and circumferential fusion of high-grade spondylolisthesis in adolescents: a prospective cohort study of 29 young patients.

AIM: The objective of this study was to evaluate the safety and efficacy of a novel technique of formal reduction and circumferential fusion for pediatric high-grade spondylolisthesis (HGS). PURPOSE: The safety and efficacy of formal reduction for high-grade spondylolisthesis (HGS) has never been thoroughly examined. This study reports the outcomes of 29 children with HGS who underwent a procedure of gradual reduction and circumferential fusion. METHODS: 29 children (13 males, 16 females) were recruited between 2006 and 2010. Radiographic measurements (including % of slip, lumbosacral angle-LSA, pelvic incidence-PI, pelvic tilt-PT, sacral slope-SS, and proximal femoral angle-PFA) and quality of life assessment (SRS-22 questionnaire) were prospectively obtained at baseline and at the last post-operative follow-up (> 2 years post-op). Radiological measurements were used to classify patients according to the Spine Deformity Study Group (SDSG) classification. RESULTS: Mean baseline slip % was 69.9 ± 16.5%. There were 13 patients with a balanced pelvic (SDSG Type 4) and 16 with an unbalanced pelvis (SDSG Type 5 and 6). On average, a reduction of 45.5 ± 15.3% (range 20-86%) was achieved safely with no major complication. In particular, of the 29 patients, only 3 had a L5 radiculopathy postoperatively that was self-resolved at follow-up. From a radiological standpoint, we observed a mean improvement of LSA from 80.3 ± 17.9° to 91.7 ± 13.6°. We also observed a statistically significant improvement in global HRQOL, and in the function and body image domains. CONCLUSION: This prospective study suggests that formal reduction of HGS followed by circumferential fusion is safe when using a standardized surgical technique based on gradual reduction. Performing this intervention could also help improve QOL in some patients.

Clinical Relevance of Painful Congenital Early-onset Scoliosis: A Magnetic Resonance Image-based Study.

BACKGROUND: Back pain, as a clinical marker in scoliosis, has been associated with underlying pathology for many years, warranting further magnetic resonance imaging (MRI). Failures of segmentation, mixed defects, female gender, rib anomalies, congenital thoracic anomalies, and neurocutaneous markers are known risk factors for abnormal MRI pathology findings in patients with congenital early-onset scoliosis (Congenital-EOS). Yet, back pain has not been evaluated as a risk factor for underlying MRI pathology in patients with Congenital-EOS. This study aimed to assess back pain as a risk factor for underlying pathology in Congenital-EOS using MRI as a diagnostic tool. METHODS: A retrospective database review from the Pediatric Spine Study Group (PSSG) of all patients with Congenital-EOS who reported a back pain complaint, and underwent a spinal MRI study before surgical intervention was performed. Patients were divided into those with an underlying MRI pathology and those without. Demographics were compared between groups. RESULTS: From a total of 2355 patients with Congenital-EOS registered in PSSG, 107 patients reported a back pain complaint, with only 42 patients fulfilling the inclusion criteria (being evaluated with an MRI study). Overall group mean age was 8.1±4.5 years, with 25 of the 42 patients (60%) being females. Twenty-four of 42 patients (57%) had a comorbidity reported such as cardiac problems, musculoskeletal complaints, neurological deficits/myelopathy, gastrointestinal symptoms, developmental delay, respiratory problems, craniofacial abnormalities, and chromosomal conditions. An underlying MRI pathology was found in 21 of 42 patients with Congenital-EOS (50%) with back pain. The underlying MRI pathologies found were tethered spinal cord, spinal canal stenosis, syringomyelia, Arnold-Chiari malformation, and arachnoid cyst. CONCLUSIONS: Abnormal MRI findings are common in patients with Congenital-EOS who report back pain. Gender, age, major coronal curve angle, thoracic or lumbar predominance deformity, and comorbidities type or amount were not associated with abnormal MRI findings. LEVEL OF EVIDENCE: Level II-Prognostic study.

Is it safe to initiate activity-based therapy within days following traumatic spinal cord injury? Preliminary results from the PROMPT-SCI trial.

CONTEXT: Activity-based therapy initiated within days of the accident could prevent complications and improve neurofunctional outcomes in patients with traumatic spinal cord injury (TSCI). However, it has never been attempted in humans with TSCI because of practical obstacles and potential safety concerns. The PROMPT-SCI trial is the first attempt at implementing ABT within the first days following a TSCI (i.e. very early ABT; VE-ABT). The objective is to determine if VE-ABT can be initiated safely in the intensive care unit (ICU) within 48 h of early decompressive surgery. DESIGN: As part of the PROMPT-SCI trial, 15 adult patients with severe TSCI were enrolled between April and November of 2021. The intervention consisted of 30-minute sessions of motor-assisted in-bed leg cycling starting within 48 h of early spinal surgery. Safety was assessed through continuous monitoring of vital signs and recording of adverse events during and after sessions. The main outcome measure was the achievement (yes or no) of a full and safe session within 48 h of early surgery. FINDINGS: Out of the 15 participants, 10 (66.6%) achieved this outcome. Out of the remaining 5, 2 were not cleared to engage in cycling within 48 h of surgery and 3 initiated cycling within 48 h but stopped prematurely. All 5 eventually completed a full and safe session within the next 1-2 days. In all 15 participants, there were no neurological deteriorations after the first completed session. CONCLUSION: Our results suggest that it is safe and feasible to perform a first session of VE-ABT within days of a severe TSCI with no serious adverse events and excellent completion rates.

A Surgical Treatment Algorithm for Restoring Pelvic Balance and Health-related Quality of Life in High-grade Lumbosacral Spondylolisthesis: Prospective Multicenter Cohort of 61 Young Patients.

STUDY DESIGN: Retrospective multicenter cohort-study. OBJECTIVE: We propose an evidence-based surgical algorithm for achieving normal pelvic balance while optimizing health-related quality of life (HRQoL) in high-grade spondylolisthesis. SUMMARY OF BACKGROUND DATA: The principles of surgical treatment for young patients with high-grade L5-S1 spondylolisthesis remain unclear. There is a growing body of evidence supporting the central role of pelvic balance in the postural control and biomechanics of subjects with high-grade spondylolisthesis. METHODS: This retrospective study assessed a multicenter cohort of 61 patients with high-grade L5-S1 spondylolisthesis. Classification and regression tree analysis was used to identify objective criteria associated with pelvic balance and HRQoL after surgery. RESULTS: The most important predictor of a postoperative balanced pelvis was a postoperative L5 incidence ≤63.5 degrees. With postoperative L5 incidence ≤63.5 degrees,a residual slip percentage 9% and performing an L5-S1 posterior lumbar interbody fusion (PLIF)/transforaminal lumbar interbody fusion (TLIF) increased the likelihood of achieving a balanced pelvis postoperatively. When L5 incidence was 63.5 degrees,a balanced pelvis was most likely achieved with fusion limited to L5 proximally, residual slip percentage ≤40%, and residual lumbosacral angle 98 degrees. Predictors of postoperative HRQoL were the preoperative HRQoL score, L5 incidence and slip percentage. CONCLUSIONS: A surgical algorithm is proposed to achieve normal pelvic balance, while optimizing HRQoL. The first step during surgery is to assess L5 incidence and if L5 incidence is <65 degrees, the next step depends on the pelvic balance. With a preoperative balanced pelvis, it is important not to reduce completely the slip percentage by leaving a slip percentage ≥10%. When the preoperative pelvis is unbalanced, a TLIF/PLIF at L5-S1 is recommended to facilitate correcting the angular deformity at L5-S1. If L5 incidence is ≥65 degrees,a TLIF/PLIF at L5-S1 should be performed to correct the angular deformity at L5-S1, and fusion should ideally end at L5 proximally, in addition to performing gradual reduction of the slip percentage. If fusion up to L4 is required, a lumbosacral angle ≥100 degrees is key.

How do early perioperative changes in AIS grade correlate with long-term neurological recovery? A retrospective cohort study.

CONTEXT/OBJECTIVE: Providing accurate counseling on neurological recovery is crucial after traumatic spinal cord injury (TSCI). The early neurological changes that occur in the subacute phase of the injury (i.e. within 14 days of early decompressive surgery) have never been documented. The objective of this study was to assess peri-operative neurological improvements after acute TSCI and determine their relationship with long-term neurological outcomes, measured 6-12 months following the injury. METHODS: A retrospective cohort study of 142 adult TSCI patients was conducted. Early peri-operative improvement was defined as improvement of at least 1 AIS grade between the pre-operative and follow-up (6-12 months post-TSCI) assessment. neurological improvement of at least 1 AIS grade. RESULTS: Out of the 142 patients, 18 achieved a peri-operative improvement of at least 1 AIS grade. Presenting a pre-operative AIS grade B and having shorter surgical delays were the main factors associated with stronger odds of achieving this outcome. Out of the 140 patients who still had potential for improvement at the time of the post-operative assessment, 44 achieved late neurological recovery (improvement of at least 1 AIS grade between the post-operative assessment and follow-up). Patients who presented a perioperative improvement seemed more likely to achieve later neurological improvement as well, although this was not statistically significant. CONCLUSION: Our results suggest that it is important to assess early perioperative neurological changes within 14 days of surgery because it can provide beneficial insight on long-term neurological outcomes for some patients. In addition, earlier surgery may promote early neurological recovery.

Is quality of life after surgery for adolescent idiopathic scoliosis affected by the presence of a concomitant low-grade isthmic spondylolisthesis non-surgically treated? A retrospective cohort study.

PURPOSE: The HRQoL after surgery for adolescent idiopathic scoliosis (AIS) is not affected by the presence of concomitant isthmic spondylolisthesis non-surgically treated. Improvement in QoL after surgery was similar for AIS patients with and without concomitant spondylolisthesis. The purpose is to compare preoperative and postoperative Health-Related Quality of Life (HRQoL) scores in operated AIS patients with and without concomitant isthmic spondylolisthesis. METHODS: A retrospective study of a prospective cohort of 464 individuals undergoing AIS surgery between 2008 and 2018 was performed. All patients undergoing surgery for AIS with a minimum 2-year follow-up were included. We excluded patients with prior or concomitant surgery for spondylolisthesis. HRQoL scores were measured using the SRS-22 questionnaire. Comparisons were performed between AIS patients with versus without concomitant spondylolisthesis treated non-surgically. RESULTS: AIS surgery was performed for 36 patients (15.2 ± 2.5 y.o) with concomitant isthmic spondylolisthesis, and 428 patients (15.5 ± 2.4 y.o) without concomitant spondylolisthesis. The two groups were similar in terms of age, sex, preoperative and postoperative Cobb angles. Preoperative and postoperative HRQoL scores were similar between the two groups. HRQoL improved significantly for all domains in both groups, except for pain in patients with spondylolisthesis. There was no need for surgical treatment of the spondylolisthesis and no slip progression during the follow-up duration after AIS surgery. CONCLUSION: Patients undergoing surgical treatment of AIS with non-surgical management of a concomitant isthmic grade I spondylolisthesis can expect improvement in HRQoL scores, similar to that observed in patients without concomitant spondylolisthesis.

A Dangerous Curve: Impact of the COVID-19 Pandemic on Brace Treatment in Adolescent Idiopathic Scoliosis.

STUDY DESIGN: Observational Cohort study. OBJECTIVES: We aim to document the abandon and irregular compliance rate towards brace treatment during the COVID-19 pandemic and its impact on AIS progression. METHODS: We reviewed a database of AIS patients recruited between March and September 2020. We included AIS patients under brace treatment according to SRS criteria. The patients were divided in 2 cohorts: those with self-reported Good-Compliance (GC) to treatment and those who had a Bad-Compliance (BC). Data analysis included biometric and radiographic data at first visit and last follow-up and percentage of progression. Unpaired student-t tests and Chi2 were used for comparison. RESULTS: 152 patients met inclusion criteria. 89 patients (age:12.1y.o.±1.4) reported good adherence to treatment, while 63 patients (age:12.7y.o.±1.8) were not compliant. Within the BC group, 18 patients reported irregular brace wear, while 45 had completely abandoned treatment (abandon rate of 29%). The GC cohort started treatment with a mean main thoracic (MT) curve of 26° and finished with 27°. The mean difference between measurements was +.65°±7.5; mean progression rate was -4.6%. However, the BC cohort started with a mean MT curve of 27° and finished with 32°, with a mean increase of +5°±8 and a mean progression rate of -13%. The differences between the 2 cohorts were statistically significant (P = .0002). Six patients from the BC group progressed and were offered surgery. CONCLUSION: The abandon rate of brace treatment in AIS significantly increased during the first wave of COVID-19 pandemic. Patients who voluntarily discontinued treatment had significant increases in curve progression and surgical indication rates. LEVEL OF EVIDENCE: III.

Protocol for rapid onset of mobilisation in patients with traumatic spinal cord injury (PROMPT-SCI) study: a single-arm proof-of-concept trial of early in-bed leg cycling following acute traumatic spinal cord injury.

INTRODUCTION: Activity-based therapy (ABT) is an important aspect of rehabilitation following traumatic spinal cord injury (SCI). Unfortunately, it has never been adapted to acute care despite compelling preclinical evidence showing that it is safe and effective for promoting neurological recovery when started within days after SCI. This article provides the protocol for a study that will determine the feasibility and explore potential benefits of early ABT in the form of in-bed leg cycling initiated within 48 hours after the end of spinal surgery for SCI. METHODS AND ANALYSIS: PROMPT-SCI (protocol for rapid onset of mobilisation in patients with traumatic SCI) is a single-site single-arm proof-of-concept trial. Forty-five patients aged 18 years or older with a severe traumatic SCI (American Spinal Injury Association Impairment Scale grade A, B or C) from C0 to L2 undergoing spinal surgery within 48 hours of the injury will be included. Participants will receive daily 30 min continuous sessions of in-bed leg cycling for 14 consecutive days, initiated within 48 hours of the end of spinal surgery. The feasibility outcomes are: (1) absence of serious adverse events associated with cycling, (2) completion of 1 full session within 48 hours of spinal surgery for 90% of participants and (3) completion of 11 sessions for 80% of participants. Patient outcomes 6 weeks and 6 months after the injury will be measured using neurofunctional assessments, quality of life questionnaires and inpatient length of stay. Feasibility and patient outcomes will be analysed with descriptive statistics. Patient outcomes will also be compared with a matched historical cohort that has not undergone in-bed cycling using McNemar and Student's t-tests for binary and continuous outcomes, respectively. ETHICS AND DISSEMINATION: PROMPT-SCI is approved by the Research Ethics Board of the CIUSSS NIM. Recruitment began in April 2021. Dissemination strategies include publications in scientific journals and presentations at conferences. TRIAL REGISTRATION NUMBER: NCT04699474.

Early Predictors of Neurological Outcomes After Traumatic Spinal Cord Injury: A Systematic Review and Proposal of a Conceptual Framework.

BACKGROUND: Neurological outcomes after traumatic spinal cord injury are variable and depend on patient-, trauma-, and treatment-related factors as well as on spinal cord injury characteristics, imaging, and biomarkers. OBJECTIVE: The aims of the study were to identify and classify the early predictors of neurological outcomes after traumatic spinal cord injury. DATA SOURCES: The Medline, PubMed, Embase, and the Cochrane Central Database were searched using medical subject headings. The search was extended to the reference lists of identified studies. STUDY ELIGIBILITY CRITERIA: The study eligibility criteria were assessment of neurological outcomes as primary or secondary outcome, predictors collected during the acute phase after traumatic spinal cord injury, and multivariate design. PARTICIPANTS: The participants were adult patients with traumatic spinal cord injury followed at least 3 mos after injury. STUDY APPRAISAL AND SYNTHESIS METHODS: The quality of studies was assessed by two independent reviewers using the Study Quality Assessment Tools for Observational Cohort and Cross-sectional Studies. The studies' narrative synthesis relied on a classification of the predictors according to quantity, quality, and consistency of the evidence. Results were summarized in a conceptual framework. RESULTS: Forty-nine articles were included. The initial severity of traumatic spinal cord injury (American Spinal Injury Association Impairment Scale, motor score, and neurological level of injury) was the strongest predictor of neurological outcomes: patients with more severe injury at admission presented poor neurological outcomes. Intramedullary magnetic resonance imaging signal abnormalities were also associated with neurological outcomes, as the presence of intramedullary hemorrhage was a factor of poor prognosis. Other largely studied predictors, such as age and surgical timing, showed some inconsistency in results depending on cutoffs. Younger age and early surgery were generally associated with good outcomes. Although widely studied, other factors, such as vertebral and associated injuries, failed to show association with outcomes. Cerebrospinal fluid inflammatory biomarkers, as emerging factors, were significantly associated with outcomes. CONCLUSIONS: This study provides a comprehensive review of predictors of neurological outcomes after traumatic spinal cord injury. It also highlights the heterogeneity of outcomes used by studies to assess neurological recovery. The proposed conceptual framework classifies predictors and illustrates their relationships with outcomes.

Finite element assessment of a disc-replacement implant for treating scoliotic deformity.

BACKGROUND: Bracing and spinal fusion surgery have long been the primary methods for idiopathic scoliosis correction; however, there exist multiple limitations with both techniques. Growth modulation techniques have recently been attempted, but are typically performed across multiple vertebral elements. The aim of this study was to quantify the corrective abilities of a dual-angled, wedge shaped, rigid disc implant designed to correct spinal deformity. METHODS: The 3D spinal geometry of four patients was reconstructed using calibrated radiographs, from which personal finite element models were created. Coronal and sagittal Cobb angles and axial stress distribution were calculated pre- and post- simulation of device implantation at the apical vertebral element. FINDINGS: Insertion of a rigid wedged implant resulted in up to 90.1% coronal correction with kyphotic normalization, and reduced axial stress differential within adjacent vertebrae by up to 83.3%. This correction in axial stress differential was seen to propagate to subjacent vertebrae in both rostral and caudal directions. Insertion of two implants yielded greater correction with respect to all three measures. INTERPRETATION: Local Cobb angle correction, increased kyphotic angle, and a decrease in axial stress differential with adjacent and subjacent vertebral levels demonstrate a potential for deformity correction from within the disc space. The decrease in axial stress differential demonstrates a capacity for growth modulation and reversal of the Heuter-Volkmann principle. Based on qualitative views of spinal shape following device implantation, the wedged implant proved more efficacious in correcting single thoracic curves than double major curves.

Use of Regression Tree Analysis for Predicting the Functional Outcome after Traumatic Spinal Cord Injury.

Predicting the long-term functional outcome after traumatic spinal cord injury (TSCI) is needed to adapt medical strategies and plan an optimized rehabilitation. This study investigates the use of regression trees for the development of predictive models based on acute clinical and demographic predictors. This prospective study was performed on 172 patients hospitalized after TSCI. Functional outcome was quantified using the Spinal Cord Independence Measure (SCIM) collected within the first-year post-injury. Age, delay before surgery, and Injury Severity Score (ISS) were considered as continuous predictors whereas energy of injury, trauma mechanisms, neurological level of injury, injury severity, occurrence of early spasticity, urinary tract infection, pressure ulcer, and pneumonia were coded as categorical inputs. A simplified model was built using only American Spinal Injury Association Impairment Scale grade, neurological level, energy, and age as predictor and was compared to a more complex model considering all 11 predictors mentioned above. The models built using 4 and 11 predictors were found to explain 51.4% and 62.3% of the variance of the SCIM total score after validation, respectively. Severity of the neurological deficit at admission was found to be the most important predictor. Other important predictors were the ISS, age, neurological level, and delay before surgery. Regression trees offer promising performances for predicting the functional outcome after a TSCI. It could help to determine the number and type of predictors leading to a prediction model of the functional outcome that can be used clinically in the future.

Patient outcomes in idiopathic scoliosis are associated with biological endophenotypes: 2020 SOSORT award winner.

PURPOSE: Bracing is the treatment of choice for idiopathic scoliosis (IS), unfortunately factors underlying brace response remain unknown. Clinicians are currently unable to identify patients who may benefit from bracing, and therefore, better molecular stratification is critically needed. The aim of this study is to evaluate IS patient outcomes at skeletal maturity in relation to biological endophenotypes, and determine specific endophenotypes associated to differential bracing outcomes. This is a retrospective cohort with secondary cross-sectional comparative studies. METHODS: Clinical and radiological data were collected from 563 IS patients, stratified into biological endophenotypes (FG1, FG2, FG3) based on a cell-based test. Measured outcomes were maximum Cobb angle at skeletal maturity, and if severe, spinal deformity (≥ 45°) or surgery was attained. Treatment success/failure was determined by standard progression thresholds (Cobb ≥ 45° or surgery; Cobb angle progression ≥ 6°). Multivariable analyses were performed to evaluate associations between endophenotypes and clinical outcome. RESULTS: Higher Cobb angles at maturity for FG1 and FG2 patients were observed (p = 0.056 and p = 0.05), with increased likelihood of ≥ 45° and/or surgery for FG1 (OR = 2.181 [1.002-4.749] and FG2 (OR = 2.141 [1.038-4.413]) compared to FG3. FG3 was 9.31 [2.58-33.61] and 5.63 [2.11-15.05] times more likely for bracing success at treatment termination and based on the < 6° progression criterion, respectively, compared to FG1. CONCLUSION: Associations between biological endophenotypes and outcomes suggest differences in progression and/or bracing response among IS patients. Outcomes were most favorable in FG3 patients. The results pave the way for establishing personalized treatments, distinguishing who may benefit or not from treatment.

Clinical Protocol for Identifying and Managing Bladder Dysfunction during Acute Care after Traumatic Spinal Cord Injury.

Bladder dysfunction is widespread following traumatic spinal cord injury (TSCI). Early diagnosis of bladder dysfunction is crucial in preventing complications, determining prognosis, and planning rehabilitation. We aim to suggest the first clinical protocol specifically designed to evaluate and manage bladder dysfunction in TSCI patients during acute care. A retrospective cohort study was conducted on 101 patients admitted for an acute TSCI between C1 and T12. Following spinal surgery, presence of voluntary anal contraction (VAC) was used as a criterion for removal of indwelling catheter and initiating trial of void (TOV). Absence of bladder dysfunction was determined from three consecutive post-void bladder scan residuals ≤200 mL without incontinence. All patients were reassessed 3 months post-injury using the Spinal Cord Independence Measure (SCIM). A total of 74.3% were diagnosed with bladder dysfunction during acute care, while 57.4% had a motor-complete TSCI. Three months later, 94.7% of them reported impaired bladder function. None of the patients discharged from acute care after a functional bladder was diagnosed reported impaired bladder function at the 3-month follow-up. A total of 95.7% patients without VAC had persisting impaired bladder function at follow-up. The proposed protocol is specifically adapted to the dynamic nature of neurogenic bladder function following TSCI. The assessment of VAC into the protocol provides major insight on the potential for reaching adequate bladder function during the subacute phase. Conducting TOV using bladder scan residuals in patients with VAC is a non-invasive and easy method to discriminate between a functional and an impaired bladder following acute TSCI.

The use of classification and regression tree analysis to identify the optimal surgical timing for improving neurological outcomes following motor-complete thoracolumbar traumatic spinal cord injury.

STUDY DESIGN: Observational cohort study. OBJECTIVES: To identify the optimal surgical timing for improving neurological outcomes in patients that sustained a motor-complete traumatic spinal cord injury (TSCI) secondary to a thoracolumbar injury. SETTING: Level 1 trauma center specialized in TSCI care. METHODS: We prospectively analyzed clinical data of 35 patients admitted for motor-complete TSCI secondary to a thoracolumbar injury. We quantified neurological recovery with three different outcomes: the improvement of at least one grade on the American Spinal Injury Association Impairment Scale (AIS), of at least one neurological level of injury (NLI), and of at least 10-points on the motor score (MS). Classification and regression tree analysis was used to identify outcome predictors and to provide cutoff values of surgical timing associated with recovery. RESULTS: The proportion of the patients improving by at least one AIS grade was higher in the group undergoing early surgery within 25.7 h of the TSCI (46% vs 0%). The proportion of patients that improved by at least one NLI was also higher in the group undergoing early surgery within 21.5 h of the TSCI (71% vs 18%). Lastly, 25% of the AIS grade A patients undergoing early surgery within 25.6 h of the TSCI improved 10 MS points or more as compared with 0% in the other group. CONCLUSIONS: Earlier surgery was effective in improving neurological outcome in motor-complete TSCI at the thoracolumbar levels. Performing surgery within 21.5 h from the traumatic event in these patients increases the likelihood of improving the neurological recovery. SPONSORSHIP: This study was supported by the Fonds de Recherche du Québec-Santé (FRQS), Department of the Army-United States Army Medical Research Acquisition Activity, Rick Hansen Spinal Cord Injury Registry and Medtronic research chair in spinal trauma at Université de Montréal.

Defining criteria for optimal lumbar curve correction following the selective thoracic fusion surgery in Lenke 1 adolescent idiopathic scoliosis: developing a decision tree.

OBJECTIVE: The aim of this study was to identify the range of optimal versus suboptimal rates of spontaneous lumbar Cobb correction (SLCC%) and the factors predicting such outcomes in a cohort of Lenke 1 adolescent idiopathic scoliosis (AIS) after posterior spinal fusion surgery. METHODS: Seventy-one consecutive Lenke1 B and C AIS patients with a fusion level to L1 and higher with two-year follow-up were included. Thoracic kyphosis (T1-T4 and T4-T12 TK), lumbar lordosis (L1-S1 LL), thoracic and lumbar Cobb angles, thoracic and lumbar apical vertebral rotations and translations (AVR and AVT), pelvic incidence, sacral slope, and sagittal and frontal balances were measured at preoperative, early postoperative, and two-year follow-up. The SLCC% was calculated between preoperative and two-year follow-up. A clustering analysis determined the subgroups of patients with significantly higher and lower (optimal versus suboptimal) rate of SLCC% in the cohort at two-year follow-up. The cutoff values of the preoperative and early postoperative radiographic parameters that significantly predicted the optimal and suboptimal SLCC% were determined using a decision tree. RESULTS: The averages of the optimal versus suboptimal range of SLCC% in the cohort were 72% [55%, 105%] versus 39% [- 7%, 42%]. Preoperative and early postoperative spinal parameters predicted the optimal versus suboptimal SLCC% with an accuracy of 82%, 95%CI [0.73-0.94]. Preoperative AVTLumbar < 10 mm was a predictor of optimal SLCC%. In patients with a preoperative AVTLumbar > 10 mm, early postoperative T4-T12 TK < 24° (but not less than 17°) accompanied by - 5° < AVRThoracic < 5° were the main predictors of optimal SLCC% in our cohort. CONCLUSION: Quantitative clustering of the SLCC% into optimal and suboptimal groups allowed identifying the cutoff values of preoperative (AVTLumbar) and early postoperative (T4-T12 TK and AVRThoracic) spinal parameters that can predict the optimal range of SLCC% at two-year postoperative in our cohort of Lenke 1 AIS. LEVEL OF EVIDENCE: IV.

A Predictive Model of Progression for Adolescent Idiopathic Scoliosis Based on 3D Spine Parameters at First Visit.

MINI: The aim of this prospective cohort study was to improve the prediction of curve progression in AIS. By adding the 3D morphology parameters at first visit, the predictive model explains 65% of the variability. It is one of the greatest advances in the understanding of scoliosis progression in the last 30 years. STUDY DESIGN: Prospective cohort study. OBJECTIVE: The objective of the present study was to design a model of AIS progression to predict Cobb angle at full skeletal maturity, based on curve type, skeletal maturation, and 3D spine parameters available at first visit. SUMMARY OF BACKGROUND DATA: Adolescent idiopathic scoliosis (AIS) is a three-dimensional (3D) spinal deformity that affects 1% of adolescents. Curve severity is assessed using the Cobb angle. Prediction of scoliosis progression remains challenging for the treating physician and is currently based on curve type, severity, and maturity. The objective of this study was to develop a predictive model of final Cobb angle, based on 3D spine parameters at first visit, to optimize treatment. METHODS: A prospective cohort of AIS patients at first orthopedic visit was enrolled between 2006 and 2010, all with 3D reconstructions. Measurements of five types of descriptors were obtained: angle of plane of maximum curvature, Cobb angles, 3D wedging, rotation, and torsion. A general linear model analysis with backward selection was done with final Cobb angle (either just before surgery or at skeletal maturity) as outcome and 3D spine parameters and clinical parameters as predictors. RESULTS: Of 195 participants, 172 (88%) were analyzed; average age at presentation was 12.5 ±â€Š1.3 years and mean follow-up to outcome, 3.2 years. The final model includes significant predictors: initial skeletal maturation, curve type, frontal Cobb angle, angle of plane of maximal curvature, and 3D disk wedging (T3-T4, T8-T9) and achieved a determination coefficient (R) = 0.643. Positive and negative predictive values to identify a curve of 35 degrees are 79% and 94%. CONCLUSION: This study developed a predictive model of spinal curve progression in scoliosis based on first-visit information. The model will help the treating physician to initiate appropriate treatment at first visit. LEVEL OF EVIDENCE: 3.

Prospective cohort study. The objective of the present study was to design a model of AIS progression to predict Cobb angle at full skeletal maturity, based on curve type, skeletal maturation, and 3D spine parameters available at first visit. Adolescent idiopathic scoliosis (AIS) is a three-dimensional (3D) spinal deformity that affects 1% of adolescents. Curve severity is assessed using the Cobb angle. Prediction of scoliosis progression remains challenging for the treating physician and is currently based on curve type, severity, and maturity. The objective of this study was to develop a predictive model of final Cobb angle, based on 3D spine parameters at first visit, to optimize treatment. A prospective cohort of AIS patients at first orthopedic visit was enrolled between 2006 and 2010, all with 3D reconstructions. Measurements of five types of descriptors were obtained: angle of plane of maximum curvature, Cobb angles, 3D wedging, rotation, and torsion. A general linear model analysis with backward selection was done with final Cobb angle (either just before surgery or at skeletal maturity) as outcome and 3D spine parameters and clinical parameters as predictors. Of 195 participants, 172 (88%) were analyzed; average age at presentation was 12.5 ±â€Š1.3 years and mean follow-up to outcome, 3.2 years. The final model includes significant predictors: initial skeletal maturation, curve type, frontal Cobb angle, angle of plane of maximal curvature, and 3D disk wedging (T3-T4, T8-T9) and achieved a determination coefficient (R2) = 0.643. Positive and negative predictive values to identify a curve of 35 degrees are 79% and 94%. This study developed a predictive model of spinal curve progression in scoliosis based on first-visit information. The model will help the treating physician to initiate appropriate treatment at first visit. Level of Evidence: 3.

Restoration of normal pelvic balance from surgical reduction in high-grade spondylolisthesis.

PURPOSE: To investigate the effectiveness of surgical reduction in high-grade spondylolisthesis in maintaining or restoring a normal pelvic balance, as related to the QoL. METHODS: It is a retrospective analysis of prospectively collected data of 60 patients (17 males, 43 females) aged 15 ± 3.1 years who underwent surgery for high-grade spondylolisthesis and were followed for a minimum of 2 years after surgery. Patients with a residual high-grade slip following surgery were referred to the postoperative high-grade (PHG) group, while patients with a residual low-grade slip were referred to the postoperative low-grade (PLG) group. Pelvic balance was assessed from pelvic tilt and sacral slope, in order to identify patients with a balanced pelvis or unbalanced pelvis. The SRS-22 questionnaire was completed before surgery and at last follow-up. RESULTS: Postoperatively, there were 36 patients with a balanced pelvis and 24 patients with an unbalanced pelvis. The improvement in QoL was better in patients with a postoperative balanced pelvis. There were 14 patients in the PHG group and 46 patients in the PLG group. Four of seven patients (57%) in the PHG group and 21 of 26 patients (81%) in the PLG group with a preoperative balanced pelvis maintained a balanced pelvis postoperatively (P = 0.1). None of the patients in the PHG group and 11 of 20 patients (55%) in the PLG group improved from an unbalanced to a balanced pelvis postoperatively (P < 0.05). CONCLUSIONS: Surgical reduction in high- to low-grade slip is more effective in maintaining and restoring a normal pelvic balance postoperatively. These slides can be retrieved under Electronic Supplementary Material.

Criteria for surgical reduction in high-grade lumbosacral spondylolisthesis based on quality of life measures.

PURPOSE: Although surgical reduction in high-grade lumbosacral spondylolisthesis is often performed in young patients, criteria for defining adequate reduction leading to optimal outcomes have yet to be defined. The purpose of this study is to determine if surgical reduction in pelvic balance, slip grade, lumbosacral angle and L5 incidence are associated with quality of life after surgery, based on specific criteria proposed previously in the literature. METHODS: A prospective cohort of 61 patients (14.4 ± 2.7 years) with high-grade lumbosacral spondylolisthesis was followed for a minimum of 2 years after surgery. SRS-22 scores, slip grade, lumbosacral angle, pelvic balance and L5 incidence were assessed before surgery and at the latest follow-up. Multivariable regression analyses were performed using postoperative SRS domain and total scores as the dependent variables. Independent variables consisted of the preoperative SRS scores, and specific criteria of pelvic balance, slip grade, lumbosacral angle and L5 incidence. The influence of slip grade, lumbosacral angle and L5 incidence on pelvic balance was also assessed. RESULTS: Obtaining a balanced pelvis postoperatively was mainly predictive of improved satisfaction with surgery and self-image and also tended to be associated with higher scores for other domains. Improved mental health was associated with reduction to a low-grade slip. Reduction in lumbosacral angle was not predictive of quality of life. Postoperative pelvic balance was mainly associated with preoperative pelvic balance, but there was a tendency for achieving normal pelvic balance when the postoperative L5 incidence was 60° or smaller. CONCLUSIONS: When performing surgery in young patients with high-grade lumbosacral spondylolisthesis, achieving normal pelvic balance is the key because it is associated with improved quality of life. Reduction to a low-grade slip is predictive of improved mental health, but reduction in lumbosacral angle is not associated with postoperative quality of life. There was a tendency for obtaining normal postoperative balance in patients with postoperative L5 incidence 60° or smaller. These slides can be retrieved under Electronic Supplementary Material.

Predicting lowest hemoglobin level and risk of blood transfusion in spinal fusion surgery for adolescent idiopathic scoliosis.

PURPOSE: The aim of this study was to evaluate the factors associated with timing of lowest hemoglobin (Hb) level and the need for postoperative blood transfusion in posterior spinal fusion for adolescent idiopathic scoliosis. METHODS: We conducted a retrospective review of all adolescent scoliosis patients undergoing posterior spinal fusion at our institution, 2002-2014. Surgery consisted of segmental pedicle screw fixation using multi-level pedicle screws. Blood-saving techniques were used in all patients. Data included Cobb angle, pre- and postoperative Hb levels, preoperative autologous blood donation (PABD), surgery duration, and allogeneic or autologous transfusion. We used linear and logistic regressions for statistical analysis. RESULTS: There were 456 patients (402 female, 54 male), mean age 16 ± 5 years. Lowest Hb was observed on postoperative Days 2 (32.2%) and 3 (33.3%); 45.1% of postoperative transfusions occurred on Day 2. One hundred and eighty-eight (41%) patients who provided PABD had significantly lower preoperative Hb and received more transfusions intraoperatively (22.6% vs. 5.2%) and postoperatively (20% vs. 6.3%) than others. Probability of transfusion increased 49.6 (95% CI 17.40-141.37) times with preoperative Hb < 11 g/dL as compared to preoperative Hb > 14 g/dL. Probability of transfusion increased 4.3- and 9.8-fold when surgery duration exceeded 5 and 6 h, respectively. Probability of transfusion increased 3.3- and 5.3-fold with Cobb angle > 70° and 80°, respectively. CONCLUSIONS: We identified clear patient-specific perioperative parameters that affect risk of perioperative blood transfusion, including Cobb angle, PABD and preoperative Hb. Hb measurement beyond postoperative Day 3 is considered unnecessary unless clinically indicated. These slides can be retrieved under Electronic Supplementary Material.

Long-term follow-up after surgical treatment of adolescent idiopathic scoliosis using high-density pedicle screw constructs: Is 5-year routine visit required?

PURPOSE: The objective of this study is to determine whether routine follow-up 5 years after adolescent idiopathic scoliosis (AIS) surgery is likely to affect postoperative care for patients treated with high-density pedicle screw constructs, when routine 2-year follow-up has been performed. METHODS: We reviewed 80 patients undergoing surgery for AIS using high-density pedicle screw constructs and followed routinely 2 and 5 years after surgery. Quality of life (QOL) was assessed using the SRS-30 outcome questionnaire. Reoperations occurring between 2 and 5 years after surgery were identified. RESULTS: Curve correction and QOL were similar between 2- and 5-year visits. Two patients required revision surgery after presenting during unplanned visits between the 2- and 5-year follow-ups. One patient presented at the routine 5-year visit with an asymptomatic undisplaced rod fracture without loss of correction, and it was decided to follow-up only as needed. CONCLUSIONS: In AIS patients for whom routine follow-up 2 years after surgery using high-density pedicle screw constructs was uneventful, additional routine 5-year follow-up is not likely to affect postoperative care and revision rate. Patients developing complications and needing reoperation between 2 and 5 years after surgery will most likely present during unplanned visits rather than during routine follow-up appointments. Easy access to emergent visits on an as-needed basis is therefore important for this population if routine 5-year follow-up is not planned. These slides can be retrieved under Electronic Supplementary Material.