Fear Avoidance Beliefs in Upper-Extremity Musculoskeletal Pain Conditions: Secondary Analysis of a Prospective Clinical Study on Digital Care Programs.

BACKGROUND: Fear-avoidance beliefs (FAB) have been associated with poorer prognosis and decreased adherence to exercise-based treatments in musculoskeletal (MSK) pain. However, the impact of high FAB on adherence and outcomes in upper extremity MSK (UEMSK) pain is poorly explored, particularly through exercise-based digital care programs (DCP). OBJECTIVE: Assess the adherence levels, clinical outcomes and satisfaction in patients with UEMSK pain and elevated FAB after a fully remote multimodal DCP. Associations between FABQ-PA and clinical outcomes were conducted. METHODS: Secondary analysis of an ongoing clinical trial. Participants with UEMSK pain (shoulder, elbow, and wrist/hand) and elevated FAB-physical activity (FABQ-PA ≥ 15) were included. Adherence (completion rate, sessions/week, total exercise time) and mean change in clinical outcomes-disability (QuickDASH), numerical pain score, FABQ-PA, anxiety (GAD-7), and depression (PHQ-9)-between baseline and end-of-program were assessed. Associations between FABQ-PA and clinical outcomes were conducted. RESULTS: 520 participants were included, with mean baseline FABQ-PA of 18.02 (SD 2.77). Patients performed on average 29.3 exercise sessions (2.8 sessions/week), totalizing 338.2 exercise minutes. Mean satisfaction was 8.5/10 (SD 1.7). Significant improvements were observed in all clinical outcomes. Higher baseline FAB were associated with higher baseline disability (P < .001), and smaller improvements in disability (P < .001) and pain (P = .001). Higher engagement was associated with greater improvements in FABQ-PA (P = .043) and pain (P = 0.009). CONCLUSIONS: This study provides evidence of the potential benefits of a structured and multimodal home-based DCP in the management of UEMSK pain conditions in patients with elevated FAB in a real-world context.

Distal junctional kyphosis in adult cervical deformity patients: where does it occur?

PURPOSE: To evaluate the impact of the lowest instrumented vertebra (LIV) on Distal Junctional kyphosis (DJK) incidence in adult cervical deformity (ACD) surgery. METHODS: Prospectively collected data from ACD patients undergoing posterior or anterior-posterior reconstruction at 13 US sites was reviewed up to 2-years postoperatively (n = 140). Data was stratified into five groups by level of LIV: C6-C7, T1-T2, T3-Apex, Apex-T10, and T11-L2. DJK was defined as a kyphotic increase > 10° in Cobb angle from LIV to LIV-1. Analysis included DJK-free survival, covariate-controlled cox regression, and DJK incidence at 1-year follow-up. RESULTS: 25/27 cases of DJK developed within 1-year post-op. In patients with a minimum follow-up of 1-year (n = 102), the incidence of DJK by level of LIV was: C6-7 (3/12, 25.00%), T1-T2 (3/29, 10.34%), T3-Apex (7/41, 17.07%), Apex-T10 (8/11, 72.73%), and T11-L2 (4/8, 50.00%) (p < 0.001). DJK incidence was significantly lower in the T1-T2 LIV group (adjusted residual = -2.13), and significantly higher in the Apex-T10 LIV group (adjusted residual = 3.91). In covariate-controlled regression using the T11-L2 LIV group as reference, LIV selected at the T1-T2 level (HR = 0.054, p = 0.008) or T3-Apex level (HR = 0.081, p = 0.010) was associated with significantly lower risk of DJK. However, there was no difference in DJK risk when LIV was selected at the C6-C7 level (HR = 0.239, p = 0.214). CONCLUSION: DJK risk is lower when the LIV is at the upper thoracic segment than the lower cervical segment. DJK incidence is highest with LIV level in the lower thoracic or thoracolumbar junction.

Prospective multi-centric evaluation of upper cervical and infra-cervical sagittal compensatory alignment in patients with adult cervical deformity.

PURPOSE: Reciprocal mechanisms for standing alignment have been described in thoraco-lumbar deformity but have not been studied in patients with primary cervical deformity (CD). The purpose of this study is to report upper- and infra-cervical sagittal compensatory mechanisms in patients with CD and evaluate their changes post-operatively. METHODS: Global spinal alignment was studied in a prospective database of operative CD patients. Inclusion criteria were any of the following: cervical kyphosis (CK) > 10°, cervical scoliosis > 10°, cSVA (C2-C7 Sagittal vertical axis) > 4 cm or CBVA (Chin Brow Vertical Angle) > 25°. For this study, patients who had previous fusion outside C2 to T4 segments were excluded. Patients were sub-classified by increasing severity of cervical kyphosis [CL (cervical lordosis): < 0°, CK-low 0°-10°, CK-high > 10°] and cSVA (cSVA-low 0-4 cm, cSVA-mid 4-6 cm, cSVA-high > 6 cm) and were compared for pre- and 3-month post-operative regional and global sagittal alignment to determine compensatory recruitment. RESULTS: 75 CD patients (mean age 61.3 years, 56% women) were included. Patients with progressively larger CK had a progressive increase in C0-C2 (CL = 34°, CK-low = 37°, CK-high = 44°, p = 0.004), C2Slope and T1Slope-CL (p < 0.05). As the cSVA increased, there was progressive increase in C2Slope, T1Slope and TS-CL (p < 0.05) and patients compensated through increasing C0-C2 (cSVA-low = 33°, cSVA-mid = 40°, cSVA-high = 43°, p = 0.007) and pelvic tilt (cSVA-low = 14.9°, cSVA-mid = 24.1°, cSVA-high = 24.9°, p = 0.02). At 3 months post-op, with significant improvement in cervical alignment, there was relaxation of C0-C2 (39°-35°, p = 0.01) which positively correlated with magnitude of deformity correction. CONCLUSIONS: Patients with cervical malalignment compensate with upper cervical hyper-lordosis, presumably for the maintenance of horizontal gaze. As cSVA increases, patients also tend to exhibit increased pelvic retroversion. Following surgical treatment, there was relaxation of upper cervical compensation.

External validation of the adult spinal deformity (ASD) frailty index (ASD-FI).

PURPOSE: To assess the ability of the recently developed adult spinal deformity frailty index (ASD-FI) to predict odds of perioperative complications, odds of reoperation, and length of hospital stay after adult spinal deformity (ASD) surgery using a database other than the one used to create the index. METHODS: We used the ASD-FI to calculate frailty scores for 266 ASD patients who had minimum postoperative follow-up of 2 years in the European Spine Study Group (ESSG) database. Patients were enrolled from 2012 through 2013. Using ASD-FI scores, we categorized patients as not frail (NF) (< 0.3 points), frail (0.3-0.5 points), or severely frail (SF) (> 0.5 points). Multivariable logistic regression, adjusted for preoperative and surgical factors such as operative time and blood loss, was performed to determine the relationship between ASD-FI category and odds of major complications, odds of reoperation, and length of hospital stay. RESULTS: We categorized 135 patients (51%) as NF, 90 patients (34%) as frail, and 41 patients (15%) as SF. Overall mean ASD-FI score was 0.29 (range 0-0.8). The adjusted odds of experiencing a major intraoperative or postoperative complication (OR 4.5, 95% CI 2.0-10) or having a reoperation (OR 3.9, 95% CI 1.7-8.9) were higher for SF patients compared with NF patients. Mean hospital stay was 2.1 times longer (95% CI 1.8-2.4) for SF patients compared with NF patients. CONCLUSIONS: Greater patient frailty, as measured by the ASD-FI, is associated with longer hospital stays and greater odds of major complications and reoperation. These slides can be retrieved under Electronic Supplementary Material.

Development of a validated computer-based preoperative predictive model for pseudarthrosis with 91% accuracy in 336 adult spinal deformity patients.

OBJECTIVEPseudarthrosis can occur following adult spinal deformity (ASD) surgery and can lead to instrumentation failure, recurrent pain, and ultimately revision surgery. In addition, it is one of the most expensive complications of ASD surgery. Risk factors contributing to pseudarthrosis in ASD have been described; however, a preoperative model predicting the development of pseudarthrosis does not exist. The goal of this study was to create a preoperative predictive model for pseudarthrosis based on demographic, radiographic, and surgical factors.METHODSA retrospective review of a prospectively maintained, multicenter ASD database was conducted. Study inclusion criteria consisted of adult patients (age ≥ 18 years) with spinal deformity and surgery for the ASD. From among 82 variables assessed, 21 were used for model building after applying collinearity testing, redundancy, and univariable predictor importance ≥ 0.90. Variables included demographic data along with comorbidities, modifiable surgical variables, baseline coronal and sagittal radiographic parameters, and baseline scores for health-related quality of life measures. Patients groups were determined according to their Lenke radiographic fusion type at the 2-year follow-up: bilateral or unilateral fusion (union) or pseudarthrosis (nonunion). A decision tree was constructed, and internal validation was accomplished via bootstrapped training and testing data sets. Accuracy and the area under the receiver operating characteristic curve (AUC) were calculated to evaluate the model.RESULTSA total of 336 patients were included in the study (nonunion: 105, union: 231). The model was 91.3% accurate with an AUC of 0.94. From 82 initial variables, the top 21 covered a wide range of areas including preoperative alignment, comorbidities, patient demographics, and surgical use of graft material.CONCLUSIONSA model for predicting the development of pseudarthrosis at the 2-year follow-up was successfully created. This model is the first of its kind for complex predictive analytics in the development of pseudarthrosis for patients with ASD undergoing surgical correction and can aid in clinical decision-making for potential preventative strategies.

Three-column osteotomy for correction of cervical and cervicothoracic deformities: alignment changes and early complications in a multicenter prospective series of 23 patients.

PURPOSE: Three-column osteotomy (3CO), including pedicle subtraction osteotomy (PSO) and vertebral column resection (VCR), can provide powerful alignment correction for adult cervical deformity (ACD). Our objective was to assess alignment changes and early complications associated with 3CO for ACD. METHODS: ACD patients treated with 3CO with minimum 90-day follow-up were identified from a prospectively collected multicenter ACD database. Complications within 90-days of surgery and pre- and postoperative radiographs were collected. RESULTS: All 23 ACD patients treated with 3CO (14 PSO/9 VCR) had minimum 90-day follow-up (mean age 62.3 years, previous cervical/cervicothoracic instrumentation in 52.2% and thoracic/thoracolumbar instrumentation in 47.8%). The primary diagnosis was kyphosis in 91.3% and coronal deformity in 8.7%. The mean number of fusion levels was 12 (range 6-18). The most common 3CO levels were T1 (39.1%), T2 (30.4%) and T3 (21.7%). Eighteen (12 major/6 minor) complications affected 13 (56.5%) patients. The most common complications were neurologic deficit (17.4%), wound infection (8.7%), distal junctional kyphosis (DJK 8.7%), and cardiorespiratory failure (8.7%). Three (13.0%) patients required re-operation within 90-days (1 each for nerve root motor deficit, DJK, and implant pain/prominence). Cervical alignment improved significantly following 3CO, including cervical lordosis (-2.8° to -12.9°, p = 0.036), C2-7 sagittal vertical axis (64.6-42.3 mm, p < 0.001), and T1 slope minus cervical lordosis (46.4°-27.0°, p < 0.001). CONCLUSIONS: Among 23 ACD patients treated with 3CO, cervical alignment improved significantly following surgery. Thirteen (56.5%) patients had at least one complication. The most common complications were neurologic deficit, infection, DJK, and cardiorespiratory failure.

Potential of predictive computer models for preoperative patient selection to enhance overall quality-adjusted life years gained at 2-year follow-up: a simulation in 234 patients with adult spinal deformity.

OBJECTIVE Patients with adult spinal deformity (ASD) experience significant quality of life improvements after surgery. Treatment, however, is expensive and complication rates are high. Predictive analytics has the potential to use many variables to make accurate predictions in large data sets. A validated minimum clinically important difference (MCID) model has the potential to assist in patient selection, thereby improving outcomes and, potentially, cost-effectiveness. METHODS The present study was a retrospective analysis of a multiinstitutional database of patients with ASD. Inclusion criteria were as follows: age ≥ 18 years, radiographic evidence of ASD, 2-year follow-up, and preoperative Oswestry Disability Index (ODI) > 15. Forty-six variables were used for model training: demographic data, radiographic parameters, surgical variables, and results on the health-related quality of life questionnaire. Patients were grouped as reaching a 2-year ODI MCID (+MCID) or not (-MCID). An ensemble of 5 different bootstrapped decision trees was constructed using the C5.0 algorithm. Internal validation was performed via 70:30 data split for training/testing. Model accuracy and area under the curve (AUC) were calculated. The mean quality-adjusted life years (QALYs) and QALYs gained at 2 years were calculated and discounted at 3.5% per year. The QALYs were compared between patients in the +MCID and -MCID groups. RESULTS A total of 234 patients met inclusion criteria (+MCID 129, -MCID 105). Sixty-nine patients (29.5%) were included for model testing. Predicted versus actual results were 50 versus 40 for +MCID and 19 versus 29 for -MCID (i.e., 10 patients were misclassified). Model accuracy was 85.5%, with 0.96 AUC. Predicted results showed that patients in the +MCID group had significantly greater 2-year mean QALYs (p = 0.0057) and QALYs gained (p = 0.0002). CONCLUSIONS A successful model with 85.5% accuracy and 0.96 AUC was constructed to predict which patients would reach ODI MCID. The patients in the +MCID group had significantly higher mean 2-year QALYs and QALYs gained. This study provides proof of concept for using predictive modeling techniques to optimize patient selection in complex spine surgery.

An assessment of frailty as a tool for risk stratification in adult spinal deformity surgery.

OBJECTIVE The goal of this study was to analyze the value of an adult spinal deformity frailty index (ASD-FI) in preoperative risk stratification. Preoperative risk assessment is imperative before procedures known to have high complication rates, such as ASD surgery. Frailty has been associated with risk of complications in trauma surgery, and preoperative frailty assessments could improve the accuracy of risk stratification by providing a comprehensive analysis of patient factors that contribute to an increased risk of complications. METHODS Using 40 variables, the authors calculated frailty scores with a validated method for 417 patients (enrolled between 2010 and 2014) with a minimum 2-year follow-up in an ASD database. On the basis of these scores, the authors categorized patients as not frail (NF) (< 0.3 points), frail (0.3-0.5 points), or severely frail (SF) (> 0.5 points). The correlation between frailty category and incidence of complications was analyzed. RESULTS The overall mean ASD-FI score was 0.33 (range 0.0-0.8). Compared with NF patients (n = 183), frail patients (n = 158) and SF patients (n = 109) had longer mean hospital stays (1.2 and 1.6 times longer, respectively; p < 0.001). The adjusted odds of experiencing a major intraoperative or postoperative complication were higher for frail patients (OR 2.8) and SF patients ( 4.1) compared with NF patients (p < 0.01). For frail and SF patients, respectively, the adjusted odds of developing proximal junctional kyphosis (OR 2.8 and 3.1) were higher than those for NF patients. The SF patients had higher odds of developing pseudarthrosis (OR 13.0), deep wound infection (OR 8.0), and wound dehiscence (OR 13.4) than NF patients (p < 0.05), and they had 2.1 times greater odds of reoperation (p < 0.05). CONCLUSIONS Greater patient frailty, as measured by the ASD-FI, was associated with worse outcome in many common quality and value metrics, including greater risk of major complications, proximal junctional kyphosis, pseudarthrosis, deep wound infection, wound dehiscence, reoperation, and longer hospital stay.

A comparative analysis of the prevalence and characteristics of cervical malalignment in adults presenting with thoracolumbar spine deformity based on variations in treatment approach over 2 years.

PURPOSE: Characteristics specific to cervical deformity (CD) concomitant with adult thoracolumbar deformity (TLD) remains uncertain, particularly regarding treatment. This study identifies cervical malalignment prevalence following surgical and conservative TLD treatment through 2 years. METHODS: Retrospective analysis of a prospective, multicenter adult spinal deformity (ASD) database. CD was defined in operative and non-operative ASD patients according to the following criteria: T1 Slope minus Cervical Lordosis (T1S-CL) ≥20°, C2-C7 Cervical Sagittal Vertical Axis (cSVA) ≥40 mm, C2-C7 kyphosis >10°. Differences in rates, demographics, health-related quality of life (HRQoL) scores for Oswestry Disability Index (ODI) and Scoliosis Research Society Questionnaire (SRS-22r), and radiographic variables were assessed between treatment groups (Op vs. Non-Op) and follow-up periods (baseline, 1-year, 2-year). RESULTS: Three hundred and nineteen (200 Op, 199 Non-Op) ASD patients were analyzed. Op patients' CD rates at 1 and 2 years were 78.9, and 63.0 %, respectively. Non-Op CD rates were 21.1 and 37.0 % at 1 and 2 years, respectively. T1S-CL mismatch and cSVA malalignment characterized Op CD at 1 and 2 years (p < 0.05). Op and Non-Op CD groups had similar cervical/global alignment at 1 year (p > 0.05 for all), but at 2 years, Op CD patients had worse thoracic kyphosis (TK), T1S-CL, CL, cSVA, C2-T3 SVA, and global SVA compared to Non-Ops (p < 0.05). Op CD patients had worse ODI, and SRS Activity at 1 and 2 years post-operative (p < 0.05), but had greater 2-year SRS Satisfaction scores (p = 0.019). CONCLUSIONS: In the first study to compare cervical malalignment at extended follow-up between ASD treatments, CD rates rose overall through 2 years. TLD surgery, resulting in higher CD rates characterized by T1S-CL and cSVA malalignment, produced poorer HRQoL. This information can aid in treatment method decision-making when cervical deformity is present concomitant with TLD.

Recovery following adult spinal deformity surgery: the effect of complications and reoperation in 149 patients with 2-year follow-up.

PURPOSE: To identify the effect of complications and reoperation on the recovery process following adult spinal deformity (ASD) surgery by examining health-related quality of life (HRQOL) measures over time via an integrated health state analysis (IHS). METHODS: A retrospective review of a multicenter, prospective ASD database was conducted. Complication number, type, and need for reoperation (REOP) or not (NOREOP) were recorded. Patients were stratified as having no complication (NOCOMP), any complication (COMP), only minor complications (MINOR) and any major complications (MAJOR). HRQOL measures included Oswestry Disability Index (ODI), Short Form-36 (SF-36), and Scoliosis Research Society-22 (SRS22) at baseline, 6 weeks, 1 and 2 years postoperatively. All HRQOL scores were normalized to each patient's baseline scores and an IHS was then calculated. RESULTS: 149 patients were included. COMP, MINOR, and MAJOR had significantly lower normalized SRS mental scores at 1 and 2 years than NOCOMP (p < 0.05). REOP had significantly worse normalized 1 and 2 year mental component score (MCS), SRS mental, and total score than NOCOMP (p < 0.05). COMP, MINOR, and MAJOR all had significantly lower SRS mental IHSs than NOCOMP (p < 0.05). REOP had significantly lower IHSs for MCS and SRS satisfaction than NOREOP (p < 0.05). REOP had a significantly lower MCS and SRS mental IHS than NOCOMP (p < 0.05). CONCLUSION: An IHS analysis suggests there was a significantly protracted mental recovery phase associated with patients that had at least one complication, as well as either a minor and major complication. The addition of a reoperation also adversely affected the mental recovery as well as overall satisfaction.

Patients with spinal deformity over the age of 75: a retrospective analysis of operative versus non-operative management.

PURPOSE: The goal of the present study was to compare the outcomes of operative and non-operative patients with adult spinal deformity (ASD) over 75 years of age. METHODS: A retrospective review of a multicenter prospective adult spinal deformity database was conducted examining patients with ASD over the age of 75 years. Demographics, comorbidities, operation-related variables, complications, radiographs, and Health-related quality of life (HRQOL) measures collected included Oswestry Disability Index, Short Form-36, and Scoliosis Research Society-22 preoperatively, and at 1 and 2 years later. Minimum clinically important difference (MCID) was calculated and also compared. RESULTS: 27 patients (12 operative, 15 non-operative) were studied. There were no significant differences (p > 0.05) between operative and non-operative patients for age, body mass-index, and comorbidities, but operative patients had worse baseline HRQOL than non-operative patients. Operative patients had a significant improvement in radiographic parameters in 2-year HRQOL, whereas non-operative patients did not (p > 0.05). Operative patients were significantly more likely to reach MCID (range 41.7-81.8 vs. 0-33.3 %, p < 0.05). In the surgical group, 9 (75 %) patients had at least 1 complication (24 total complications). CONCLUSIONS: In the largest series to date comparing operative and non-operative management of adult spinal deformity in elderly patients greater than 75 years of age, reconstructive surgery provides significant improvements in pain and disability over a 2-year period. Furthermore, operative patients were more likely to reach MCID than non-operative patients. When counseling elderly patients with ASD, such data may be helpful in the decision-making process regarding treatment.

Maintenance of radiographic correction at 2 years following lumbar pedicle subtraction osteotomy is superior with upper thoracic compared with thoracolumbar junction upper instrumented vertebra.

PURPOSE: The goal of this study was to characterize the spino-pelvic realignment and the maintenance of that realignment by the upper-most instrumented vertebra (UIV) for adult deformity spinal (ASD) patients treated with lumbar pedicle subtraction osteotomy (PSO). METHODS: ASD patients were divided by UIV, classified as upper thoracic (UT: T1-T6) or Thoracolumbar (TL: T9-L1). Complications were recorded and radiographic parameters included thoracic kyphosis (TK, T2-T12), lumbar lordosis (LL, L1-S1), sagittal vertical axis (SVA), pelvic tilt, and the mismatch between pelvic incidence and LL. Patients were also classified by the Scoliosis Research Society (SRS)-Schwab modifier grades. Changes in radiographic parameters and SRS-Schwab grades were evaluated between the two groups. Additional analyses were performed on patients with pre-operative SVA ≥ 15 cm. RESULTS: 165 patients were included (UT: 81 and TL: 84); 124 women, 41 men, with average age 59.9 ± 11.1 years (range 25-81). UT had a lower percentage of patients above the radiographic thresholds for disability than TL. UT had a significantly higher percentage of patients that improved in SRS-Schwab global alignment grade than the TL group at 2 years. Within the patients with pre-operative SVA ≥ 15 cm, TL developed significantly increased SVA and had a significantly higher percentage of patients above the SVA threshold at 3 months, and 1 and 2 years than UT. CONCLUSIONS: Patients undergoing a single-level PSO for ASD who have fixation extending to the UT region (T1-T6) are more likely to maintain sagittal spino-pelvic alignment, lower overall revision rates and revision rate for proximal junctional kyphosis than those with fixation terminating in the TL region (T9-L1).

Anatomy and biomechanics of the craniovertebral junction.

The craniovertebral junction (CVJ) has unique anatomical structures that separate it from the subaxial cervical spine. In addition to housing vital neural and vascular structures, the majority of cranial flexion, extension, and axial rotation is accomplished at the CVJ. A complex combination of osseous and ligamentous supports allow for stability despite a large degree of motion. An understanding of anatomy and biomechanics is essential to effectively evaluate and address the various pathological processes that may affect this region. Therefore, the authors present an up-to-date narrative review of CVJ anatomy, normal and pathological biomechanics, and fixation techniques.

Evidence-based management of traumatic thoracolumbar burst fractures: a systematic review of nonoperative management.

OBJECT: The overall evidence for nonoperative management of patients with traumatic thoracolumbar burst fractures is unknown. There is no agreement on the optimal method of conservative treatment. Recent randomized controlled trials that have compared nonoperative to operative treatment of thoracolumbar burst fractures without neurological deficits yielded conflicting results. By assessing the level of evidence on conservative management through validated methodologies, clinicians can assess the availability of critically appraised literature. The purpose of this study was to examine the level of evidence for the use of conservative management in traumatic thoracolumbar burst fractures. METHODS: A comprehensive search of the English literature over the past 20 years was conducted using PubMed (MEDLINE). The inclusion criteria consisted of burst fractures resulting from a traumatic mechanism, and fractures of the thoracic or lumbar spine. The exclusion criteria consisted of osteoporotic burst fractures, pathological burst fractures, and fractures located in the cervical spine. Of the studies meeting the inclusion/exclusion criteria, any study in which nonoperative treatment was used was included in this review. RESULTS: One thousand ninety-eight abstracts were reviewed and 447 papers met inclusion/exclusion criteria, of which 45 were included in this review. In total, there were 2 Level-I, 7 Level-II, 9 Level-III, 25 Level-IV, and 2 Level-V studies. Of the 45 studies, 16 investigated conservative management techniques, 20 studies compared operative to nonoperative treatments, and 9 papers investigated the prognosis of conservative management. CONCLUSIONS: There are 9 high-level studies (Levels I-II) that have investigated the conservative management of traumatic thoracolumbar burst fractures. In neurologically intact patients, there is no superior conservative management technique over another as supported by a high level of evidence. The conservative technique can be based on patient and surgeon preference, comfort, and access to resources. A high level of evidence demonstrated similar functional outcomes with conservative management when compared with open surgical operative management in patients who were neurologically intact. The presence of a neurological deficit is not an absolute contraindication for conservative treatment as supported by a high level of evidence. However, the majority of the literature excluded patients with neurological deficits. More evidence is needed to further classify the appropriate burst fractures for conservative management to decrease variables that may impact the prognosis.

Artificial Intelligence in Spine Surgery.

The amount and quality of data being used in our everyday lives continue to advance in an unprecedented pace. This digital revolution has permeated healthcare, specifically spine surgery, allowing for very advanced and complex computational analytics, such as artificial intelligence (AI) and machine learning (ML). The integration of these methods into clinical practice has just begun, and the following review article will describe AI/ML, demonstrate how it has been applied in adult spinal deformity surgery, and show its potential to improve patient care touching on future directions.

Acute hyponatremia post craniotomy resulting in a unilateral fixed and dilated pupil: A case study on diagnosis and management.

Background: Postoperative hyponatremia is a known complication of intracranial surgery, which can present with depressed mental status. Hyponatremia resulting in focal neurologic deficits is less frequently described. Case Description: We describe a patient who, after a bifrontal craniotomy for olfactory groove meningioma, developed acute hyponatremia overnight with a decline in mental status from Glasgow coma scale (GCS) score 15 to GCS 7 and a unilateral fixed dilated pupil. Head computed tomography showed expected postoperative changes without new acute or localizing findings, such as unilateral uncal herniation. The patient's mental status and pupil immediately improved with the administration of mannitol; however, there was a subsequent decline in mental status with a preserved pupil later that morning. Hypertonic saline reversed the neurologic change, and the patient was eventually discharged without a neurologic deficit. Focal neurologic deficits need not always arise following a craniotomy from a postoperative hematoma, stroke, or other finding with radiographic correlate. Conclusion: Post-craniotomy hyponatremia should now be seen as a postoperative complication that can result in both a general neurologic decline in mental status, as well as with focal neurologic signs such as a fixed, dilated pupil, which can be reversed with hyperosmolar therapy and correction of the hyponatremia.

Completely Minimally Invasive Implant Removal and Transforaminal Lumbar Interbody Fusion for Adjacent Segment Disease: Case Series and Operative Video.

BACKGROUND AND OBJECTIVES: Adjacent segment disease is a relatively common late complication after lumbar fusion. If symptomatic, certain patients require fusion of the degenerated adjacent segment. Currently, there are no posterior completely minimally invasive techniques described for fusion of the adjacent segment above or below a previous fusion. We describe here a novel minimally invasive technique for both implant removal (MIS-IR) and adjacent level transforaminal lumbar interbody fusion (MIS-TLIF) for lumbar stenosis. METHODS: Demographic, surgical, and radiographic outcome data were collected for patients with lumbar stenosis and previous lumbar fusion, who were treated with MIS-IR and MIS-TLIF through the same incision. Radiographic outcomes were assessed postoperatively and complications were assessed at the primary end point of 3 months. RESULTS: A total of 14 patients (7 female and 7 male), with average age 64.6 years (SD 13.4), were included in this case series. Nine patients had single-level MIS-IR with single-level MIS-TLIF. Three patients had 2-level MIS-IR with single-level MIS-TLIF. Two patients had single-level MIS-IR with 2-level MIS-TLIF. Only 1 patient had a postoperative complication-hematoma requiring same-day evacuation. There were no other complications at the primary end point and no fusion failure at the hardware removal levels to date (average follow-up, 11 months). Average increases in posterior disk height and foraminal height after MIS-TLIF were 4.44, and 2.18 mm, respectively. CONCLUSION: Minimally invasive spinal IR can be successfully completed along with adjacent level TLIF through the same incisions, via an all-posterior approach.

Epigenetic age biomarkers and risk assessment in adult spinal deformity: a novel association of biological age with frailty and disability.

OBJECTIVE: Surgery for spinal deformity has the potential to improve pain, disability, function, self-image, and mental health. These surgical procedures carry significant risk and require careful selection, optimization, and risk assessment. Epigenetic clocks are age estimation tools derived by measuring the methylation patterns of specific DNA regions. The study of biological age in the adult deformity population has the potential to shed insight onto the molecular basis of frailty and to improve current risk assessment tools. METHODS: Adult patients who underwent deformity surgery were prospectively enrolled. Preoperative whole blood samples were used to assess epigenetic age and telomere length. DNA methylation patterns were quantified and processed to extract 4 principal component (PC)-based epigenetic age clocks (PC Horvath, PC Hannum, PC PhenoAge, and PC GrimAge) and the instantaneous pace of aging (DunedinPACE). Telomere length was assessed using both quantitative polymerase chain reaction (telomere to single gene [T/S] ratio) and a methylation-based telomere estimator (PC DNAmTL). Patient demographic and surgical data included age, BMI, American Society of Anesthesiologists Physical Status Classification System class, and scores on the Charlson Comorbidity Index, adult spinal deformity frailty index (ASD-FI), Edmonton Frail Scale (EFS), Oswestry Disability Index, and Scoliosis Research Society-22r questionnaire (SRS-22r). Medical or surgical complications within 90 days of surgery were collected. Spearman correlations and beta coefficients (ß) from linear regression, adjusted for BMI and sex, were calculated. RESULTS: Eighty-three patients were enrolled with a mean age of 65 years, and 45 were women (54%). All patients underwent posterior fusion with a mean of 11 levels fused and 33 (40%) 3-column osteotomies were performed. Among the epigenetic clocks adjusted for BMI and sex, DunedinPACE showed a significant association with ASD-FI (ß = 0.041, p = 0.002), EFS (ß = 0.696, p = 0.026), and SRS-22r (ß = 0.174, p = 0.013) scores. PC PhenoAge showed associations with ASD-FI (ß = 0.029, p = 0.028) and SRS-22r (ß = 0.159, p = 0.018) scores. PC GrimAge showed associations with ASD-FI (ß = 0.029, p = 0.037) and SRS-22r (ß = 0.161, p = 0.025) scores. Patients with postoperative complications were noted to have shorter telomere length (T/S 0.790 vs 0.858, p = 0.049), even when the analysis controlled for BMI and sex (OR = 1.71, 95% CI 1.07-2.87, p = 0.031). CONCLUSIONS: Epigenetic clocks showed significant associations with markers of frailty and disability, while patients with postoperative complications had shorter telomere length. These data suggest a potential role for aging biomarkers as components of surgical risk assessment. Integrating biological age into current risk calculators may improve their accuracy and provide valuable information for patients, surgeons, and payers.

Patient-specific Cervical Deformity Corrections With Consideration of Associated Risk: Establishment of Risk Benefit Thresholds for Invasiveness Based on Deformity and Frailty Severity.

STUDY DESIGN/SETTING: This was a retrospective cohort study. BACKGROUND: Little is known of the intersection between surgical invasiveness, cervical deformity (CD) severity, and frailty. OBJECTIVE: The aim of this study was to investigate the outcomes of CD surgery by invasiveness, frailty status, and baseline magnitude of deformity. METHODS: This study included CD patients with 1-year follow-up. Patients stratified in high deformity if severe in the following criteria: T1 slope minus cervical lordosis, McGregor's slope, C2-C7, C2-T3, and C2 slope. Frailty scores categorized patients into not frail and frail. Patients are categorized by frailty and deformity (not frail/low deformity; not frail/high deformity; frail/low deformity; frail/high deformity). Logistic regression assessed increasing invasiveness and outcomes [distal junctional failure (DJF), reoperation]. Within frailty/deformity groups, decision tree analysis assessed thresholds for an invasiveness cutoff above which experiencing a reoperation, DJF or not achieving Good Clinical Outcome was more likely. RESULTS: A total of 115 patients were included. Frailty/deformity groups: 27% not frail/low deformity, 27% not frail/high deformity, 23.5% frail/low deformity, and 22.5% frail/high deformity. Logistic regression analysis found increasing invasiveness and occurrence of DJF [odds ratio (OR): 1.03, 95% CI: 1.01-1.05, P =0.002], and invasiveness increased with deformity severity ( P <0.05). Not frail/low deformity patients more often met Optimal Outcome with an invasiveness index <63 (OR: 27.2, 95% CI: 2.7-272.8, P =0.005). An invasiveness index <54 for the frail/low deformity group led to a higher likelihood of meeting the Optimal Outcome (OR: 9.6, 95% CI: 1.5-62.2, P =0.018). For the frail/high deformity group, patients with a score <63 had a higher likelihood of achieving Optimal Outcome (OR: 4.8, 95% CI: 1.1-25.8, P =0.033). There was no significant cutoff of invasiveness for the not frail/high deformity group. CONCLUSIONS: Our study correlated increased invasiveness in CD surgery to the risk of DJF, reoperation, and poor clinical success. The thresholds derived for deformity severity and frailty may enable surgeons to individualize the invasiveness of their procedures during surgical planning to account for the heightened risk of adverse events and minimize unfavorable outcomes.

Contemporary utilization of three-column osteotomy techniques in a prospective complex spinal deformity multicenter database: implications on full-body alignment and perioperative course.

BACKGROUND: Research has focused on the increased correction from a three-column osteotomy (3CO) during adult spinal deformity (ASD) surgery. However, an in-depth analysis on the performance of a 3CO in a cohort of complex spinal deformity cases has not been described. STUDY DESIGN/SETTING: This is a retrospective study on a prospectively enrolled, complex ASD database. PURPOSE: This study aimed to determine if three-column osteotomies demonstrate superior benefit in correction of complex sagittal deformity at the cost of increased perioperative complications. METHODS: Surgical complex adult spinal deformity patients were included and grouped into thoracolumbar 3COs compared to those who did not have a 3CO (No 3CO) (remaining cohort). Rigid deformity was defined as ΔLL less than 33% from standing to supine. Severe deformity was defined as global (SVA > 70 mm) or C7-PL > 70 mm, or lumbopelvic (PI-LL > 30°). Means comparison tests assessed correction by 3CO grade/location. Multivariate analysis controlling for baseline deformity evaluated outcomes up to six weeks compared to No 3CO. RESULTS: 648 patients were included (Mean age 61 ± 14.6 years, BMI 27.55 ± 5.8 kg/m2, levels fused: 12.6 ± 3.8). 126 underwent 3CO, a 20% higher usage than historical cohorts. 3COs were older, frail, and more likely to undergo revision (OR 5.2, 95% CI [2.6-10.6]; p < .001). 3COs were more likely to present with both severe global/lumbopelvic deformity (OR 4), 62.4% being rigid. 3COs had greater use of secondary rods (OR 4st) and incurred 4 times greater risk for: massive blood loss (> 3500 mL), longer LOS, SICU admission, perioperative wound and spine-related complications, and neurologic complications when performed below L3. 3COs had similar HRQL benefit, but higher perioperative opioid use. Mean segmental correction increased by grade (G3-21; G4-24; G5-27) and was 4 × greater than low-grade osteotomies, especially below L3 (OR 12). 3COs achieved 2 × greater spinopelvic correction. Higher grades properly distributed lordosis 50% of the time except L5. Pelvic compensation and non-response were relieved more often with increasing grade, with greater correction in all lower extremity parameters (p < .01). Due to the increased rate of complications, 3COs trended toward higher perioperative cost ($42,806 vs. $40,046, p = .086). CONCLUSION: Three-column osteotomy usage in contemporary complex spinal deformities is generally limited to more disabled individuals undergoing the most severe sagittal and coronal realignment procedures. While there is an increased perioperative cost and prolongation of length of stay with usage, these techniques represent the most powerful realignment techniques available with a dramatic impact on normalization at operative levels and reciprocal changes.