A Novel Preoperative Scoring System to Accurately Predict Cord-Level Intraoperative Neuromonitoring Data Loss During Spinal Deformity Surgery: A Machine-Learning Approach.

Background: An accurate knowledge of a patient's risk of cord-level intraoperative neuromonitoring (IONM) data loss is important for an informed decision-making process prior to deformity correction, but no prediction tool currently exists.

Methods: A total of 1,106 patients with spinal deformity and 205 perioperative variables were included. A stepwise machine-learning (ML) approach using random forest (RF) analysis and multivariable logistic regression was performed.

Comparison of clinical and radiological outcomes of three-column lumbar osteotomies with and without interbody cages for adult spinal deformity.

Background Context: Correcting sagittal malalignment in adult spinal deformity (ASD) is a challenging task, often requiring complex surgical interventions like pedicle subtraction osteotomies (PSOs). Different types of three-column osteotomies (3COs), including Schwab 3, Schwab 4, Schwab 4 with interbody cages, and the "sandwich" technique, aim to optimize alignment and fusion outcomes. The role of interbody cages in enhancing fusion and segmental correction remains unclear.

Comparative Analysis of Outcomes in Adult Spinal Deformity Patients with Proximal Junctional Kyphosis or Failure Initially Fused to Upper Versus Lower Thoracic Spine.

Patients with proximal junctional kyphosis (PJK) or failure (PJF) may demonstrate disparate outcomes and recovery when fused to the upper (UT) versus lower (LT) thoracic spine. Few studies have distinguished the reoperation and recovery abilities of patients with PJK or PJF when fused to the upper (UT) versus lower (LT) thoracic spine. Adult spine deformity patients ≥ 18 yrs with preoperative and 5-year (5Y) data fused to the sacrum/pelvis were included.

The gap between surgeon goal and achieved sagittal alignment in adult cervical spine deformity surgery.

Objective: Malalignment following cervical spine deformity (CSD) surgery can negatively impact outcomes and increase complications. Despite the growing ability to plan alignment, it remains unclear whether preoperative goals are achieved with surgery. The objective of this study was to assess how good surgeons are at achieving their preoperative goal alignment following CSD surgery.

Maintaining stability at the lumbosacral-pelvic region in adult spinal deformity surgery without sacroiliac joint fusion: are 4 pelvic screws superior to 2 pelvic screws?

Objective: The objective of this study was to compare a multiple pelvic screw fixation strategy (dual bilateral 4 pelvic screw fixation [4PvS]) with the use of single bilateral 2 pelvic screw fixation (2PvS), with the aim of addressing lumbosacral junction stability.

Methods: This analysis is a single-center, retrospective review of ASD patients treated between 2015 and 2021. All patients had a minimum 2-year follow-up and spinal fusion to the sacrum without sacroiliac fusion and met at least one radiographic and procedural criterion: pelvic incidence-lumbar lordosis ≥ 20°, T1 pelvic angle ≥ 20°, sagittal vertical axis ≥ 7.

Redefining Clinically Significant Blood Loss in Complex Adult Spine Deformity Surgery.

Study Design: Retrospective analysis of prospectively-collected data.

Objective: This study aims to define clinically relevant blood loss in adult spinal deformity (ASD) surgery.

Background: Current definitions of excessive blood loss following spine surgery are highly variable and may be suboptimal in predicting adverse events (AE).

Adolescent vs. Young Adult Idiopathic Scoliosis patients: how different are their two year postoperative radiographic and clinical outcomes?

Purpose: To compare the long-term outcomes among AIS (10-18 years) and young AdIS (YAdIS) (19-40 years) patients with minimum 2 year follow up.

Methods: A retrospective review of AIS and YAdIS patients who underwent primary corrective surgery at a single center was conducted. Demographic, radiographic, operative data, patient reported outcome measures (PROMs), including the ODI and SRS-22r, and long-term complications were collected.

The benefits of touched vertebra concept for the selection of the lowest instrumented vertebra in thoracic curves of adolescent idiopathic scoliosis.

Purpose: To assess the benefits of using the touched vertebra (TV) rule in Lenke classification for thoracic curves of adolescent idiopathic scoliosis (AIS).

Methods: A total of 141 AIS patients with thoracic curves determined by Suk classification were divided based on whether the lowest instrumented vertebra (LIV) matched the TV into groups of mTV (n = 84, LIV = TV), TV- (n = 21, LIV above TV), and TV+ (n = 36, LIV below TV) for 5-year follow-up. The radiological parameters were the central sacral vertical line (CSVL)-LIV distance, distal end vertebra rotation, coronal, and sagittal parameters.

When is staging complex adult spinal deformity advantageous? Identifying subsets of patients who benefit from staged interventions.

Objective: The objective of this study was to identify baseline patient and surgical factors predictive of optimal outcomes in staged versus same-day combined-approach surgery.

Methods: Adult spinal deformity (ASD) patients with baseline and perioperative (by 6 weeks) data were stratified based on single-stage (same-day) or multistage (staged) surgery, excluding planned multiple hospitalizations. Means comparison analyses were used to assess baseline demographic, radiographic, and surgical differences between cohorts.

Making wrong site surgery a "never event" in spinal deformity surgery by use of a "landmark vertebra" to eliminate variability in identifying a target vertebral level.

Purpose: Despite the introduction of "standardized counting" methods, errors in counting spinal levels and subsequent wrong-level surgery (WLS) remain critically important patient safety concerns. Previous work by our group has documented inconsistency in the identification of T12 despite the use of these systems including the Spinal Deformity Study Group (SDSG) conventions. To assist with consistent and repeatable identification of proposed preoperative surgical levels, the current study investigates a new strategy: utilization of a "landmark vertebra".

Fractional curve following adult idiopathic scoliosis correction: impact of curve magnitude on postoperative outcomes.

Objective: The goal of this study was to assess the impact of fractional curve (FC) severity on curve progression and postoperative outcomes in patients undergoing adult idiopathic scoliosis (AdIS) correction.

Methods: Patients with AdIS who had preoperative coronal plane deformity and who had undergone thoracolumbar fusion with a lowermost instrumented vertebra (LIV) between L1 and L4 were included. Patients were stratified by 6-week postoperative FC severity (small FC, ≤ 40th percentile, large FC, ≥ 60th percentile of the entire cohort; calculated as the Cobb angle between LIV and S1) and age groups.

The Variability of the Cervicothoracic Inflection Point: A Cohort Analysis of the Multi-Ethnic Asymptomatic Normative Study (MEANS).

Study Design: Cross-sectional Cohort Study.

Objective: To determine the cervicothoracic inflection point in an asymptomatic, adult population.

Introduction: The cervicothoracic inflection point (CTIP) is an important sagittal marker to understand for patients with cervical deformities.

Impact of Knee Osteoarthritis and Arthroplasty on Full Body Sagittal Alignment in Adult Spinal Deformity Patients.

Study Design: Retrospective analysis of prospectively collected data.

Objective: This study evaluates the impact of knee osteoarthritis (OA) and knee arthroplasty on alignments and patient-reported outcomes measures (PROMS) of patients undergoing adult spinal deformity (ASD) corrective surgery.

Background: The relationship between knee OA and spinal alignment in patients with ASD is incompletely understood.

The T4-L1-Hip Axis: Sagittal Spinal Realignment Targets in Long-Construct Adult Spinal Deformity Surgery: Early Impact.

Background: Our understanding of the relationship between sagittal alignment and mechanical complications is evolving. In normal spines, the L1-pelvic angle (L1PA) accounts for the magnitude and distribution of lordosis and is strongly associated with pelvic incidence (PI), and the T4-pelvic angle (T4PA) is within 4° of the L1PA. We aimed to examine the clinical implications of realignment to a normal L1PA and T4-L1PA mismatch.

Intraoperative fluid management in adult spinal deformity surgery: variation analysis and association with outcomes.

Purpose: To evaluate the variability in intraoperative fluid management during adult spinal deformity (ASD) surgery, and analyze the association with complications, intensive care unit (ICU) requirement, and length of hospital stay (LOS).

Methods: Multicenter comparative cohort study. Patients ≥ 18 years old and with ASD were included.

Patient-Specific Rods in Adolescent and Adult Spinal Deformity Surgery: A Narrative Review.

Spinal deformity surgery often requires complex surgical interventions that can have a drastic effect on both patient quality of life and functional capacity. Modern-day corrective solutions for these deformities include spinal osteotomies, pedicle screw instrumentation, and dual/multirod constructs. These solutions are efficacious and are currently considered standard practice for spinal surgeons, but they lack individualization.

Cranial sagittal vertical axis to the hip as the best sagittal alignment predictor of patient-reported outcomes at 2 years postoperatively in adult spinal deformity surgery.

Objective: The objective was to discern whether the cranial sagittal vertical axis (CrSVA) can best predict the trajectory of patient-reported outcome measures (PROMs) at 2 years postoperatively.

Methods: This was a retrospective cohort study of prospectively collected adult spinal deformity patient data. CrSVA relative to the sacrum, hip (CrSVA-H), knee, and ankle was measured as the horizontal distance to the vertical plumb line from the nasion-inion midpoint, with positive values indicating an anterior cranium.

Use of the kickstand rod improves coronal alignment and maintains correction compared to control at 2 year follow-up.

Purpose: To assess and compare coronal alignment correction at 2 year follow-up in adult spinal deformity (ASD) patients treated with and without the kickstand rod (KSR) construct.

Methods: ASD patients who underwent posterior spinal fusion at a single-center with a preoperative coronal vertical axis (CVA) ≥ 3 cm and a minimum of 2 year clinical and radiographic follow-up were identified. Patients were divided into two groups: those treated with a KSR and those who were not.