Preoperative Electrodiagnostic Study Findings Differ Between Patients With Double-crush Syndrome and Carpal Tunnel Syndrome: A Propensity Matched Analysis.

INTRODUCTION: Double-crush syndrome (DCS) represents a condition that involves peripheral nerve compression in combination with spinal nerve root impingement. The purpose of this study was to compare electrodiagnostic study (EDS) results in patients undergoing carpal tunnel release (CTR) for carpal tunnel syndrome with those undergoing both CTR and anterior cervical diskectomy and fusion for DCS. METHODS: Patients receiving an isolated CTR were compared with those undergoing CTR and anterior cervical diskectomy and fusion within two years of CTR. The latter group was defined as our DCS cohort. Electrodiagnostic study results were collected which included sensory and motor nerve conduction data as well as electromyogram (EMG) findings. All electrodiagnostic studies were done before CTR in both sets of patients. RESULTS: Fifty-four patients with DCS and 137 CTR-only patients were included. Patients with DCS were found to have decreased sensory onset latency (3.51 vs 4.01; P = 0.015) and peak latency (4.25 vs 5.17; P = 0.004) compared with the CTR-only patients. Patients with DCS had slower wrist motor velocity (30.5 vs 47.7; P = 0.012), decreased elbow motor latency (9.62 vs 10.6; P = 0.015), and faster elbow motor velocity (56.0 vs 49.4; P = 0.031). EMG results showed that patients with DCS were more likely to have positive findings in the biceps (31.9% vs 1.96%; P < 0.001) and triceps (24.4% vs 2.97%; P < 0.001), but not abductor pollicis brevis (APB) (45.7% vs 37.9%; P = 0.459). CONCLUSION: We identified changes on EDS between patients with and without DCS. In patients with DCS, sensory nerve studies showed shorter peak and onset latency than in CTR-only patients. Interestingly, DCS and CTR-only patients had different patterns of wrist and elbow motor nerve conduction. Providers observing positive EMG findings proximal to the APB should raise their suspicion for possible cervical radiculopathy and when present with carpal tunnel syndrome-like symptoms, should also consider DCS in their diagnostic differential.

Circulating microRNAs May Be Predictive of Degenerative Cervical Myelopathy.

STUDY DESIGN: Basic Science. OBJECTIVE: The objective of this study was to identify a unique serum profile of circulating miRNAs and inflammatory markers in patients with degenerative cervical myelopathy (DCM) compared to healthy controls (HC). SUMMARY OF BACKGROUND DATA: Currently, DCM is diagnosed with a combination of history, physical examination, and close correlation to advanced imaging. To date, no serum marker has been identified to be diagnostic of this condition. METHODS: Whole venous blood was collected from patients with DCM as well as healthy age- and sex-matched controls. miRNA was extracted from venous blood and a screening analysis was initially conducted to identify miRNA dysregulation in DCM patients. RT-qPCR was used to analyze the expression of 2 specific miRNAs based on screening analysis and literature review. Bioinformatics analysis was used to identify gene networks and potential targets of the miRNA. In addition, the serum inflammatory profile of DCM and HC groups was differentiated using a pro-inflammatory panel. RESULTS: Thirty-six patients were enrolled in the DCM group (36.1% male, 61.5±9.5 y) while 35 patients were enrolled in the HC group (31.4% male, 57.5±8.9 y). Of the 15 total miRNAs differentially expressed between DCM and HC groups, two were selected for further analysis: miR-223-3p (upregulated) and miR-451a (downregulated). Functional gene network analysis revealed the highest-ranking gene network was involved in neurological disease, while the most overexpressed miRNA in this network (miR-233-3p) was noted to have over 100 targets including CDKN1B and the insulin receptor. Serum cytokine analysis showed significant upregulation of several pro-inflammatory cytokines in the DCM cohort compared to the HC group. CONCLUSION: DCM patients demonstrated a set of unique circulating miRNAs in addition to a different serum inflammatory profile compared to HC. These miRNAs may potentially serve as targets for future therapeutic intervention or diagnostic/prognostic testing.

The Relationship Between Disc Herniation Morphology and Patient-Reported Outcomes after Microdiscectomy.

OBJECTIVE: Determine if herniation morphology based on the Michigan State University Classification is associated with differences in (1) patient-reported outcome measures (or (2) surgical outcomes after a microdiscectomy. METHODS: Adult patients undergoing single-level microdiscectomy between 2014 and 2021 were identified. Demographics and surgical characteristics were collected through a query search and manual chart review. The Michigan State University classification, which assesses disc herniation laterality (zone A was central, zone B/C was lateral) and degree of extrusion into the central canal (grade 1 was up to 50% of the distance to the intra-facet line, grade >1 was beyond this line), was identified on preoperative MRIs. patient-reported outcome measures were collected at preoperative, 3-month, and 1-year postoperative time points. RESULTS: Of 233 patients, 84 had zone A versus 149 zone B/C herniations while 76 had grade 1 disc extrusion and 157 had >1 grade. There was no difference in surgical outcomes between groups (P > 0.05). Patients with extrusion grade >1 were found to have lower Physical Component Score at baseline. On bivariate and multivariable logistic regression analysis, extrusion grade >1 was a significant independent predictor of greater improvement in Physical Component Score at three months (estimate = 7.957; CI: 4.443-11.471, P < 0.001), but not at 1 year. CONCLUSIONS: Although all patients were found to improve after microdiscectomy, patients with disc herniations extending further posteriorly reported lower preoperative physical function but experienced significantly greater improvement three months after surgery. However, improvement in Visual Analog Scale Leg and back, ODI, and MCS at three and twelve months was unrelated to laterality or depth of disc herniation.

Do Busier Surgeons Have Lower Intraoperative Costs? An Analysis of Anterior Cervical Discectomy and Fusion Using Time-Driven Activity-Based Costing.

STUDY DESIGN: The present study is a single-center, retrospective cohort study of patients undergoing neurosurgical anterior cervical discectomy and fusion (ACDF). OBJECTIVE: Our objective was to use time-driven activity-based costing (TDABC) methodology to determine whether surgeons' case volume influenced the true intraoperative costs of ACDFs performed at our institution. SUMMARY OF BACKGROUND DATA: Successful participation in emerging reimbursement models, such as bundled payments, requires an understanding of true intraoperative costs, as well as the modifiable drivers of those costs. Certain surgeons may have cost profiles that are favorable for these "at-risk" reimbursement models, while other surgeons may not. METHODS: Total cost was divided into direct and indirect costs. Individual costs were obtained by direct observation, electronic medical records, and through querying multiple departments (business operations, sterile processing, plant operations, and pharmacy). Timestamps for all involved personnel and material resources were documented. All surgeons performing ACDFs at our primary and affiliated hospital sites from 2017 to 2022 were divided into four volume-based cohorts: 1-9 cases (n=10 surgeons, 38 cases), 10-29 cases (n=7 surgeons, 126 cases), 30-100 cases (n=3 surgeons, 234 cases), and > 100 cases (n=2 surgeons, 561 cases). RESULTS: The average total intraoperative cost per case was $7,116 +/- $2,945. The major cost contributors were supply cost ($4,444, 62.5%) and personnel cost ($2,417, 34.0%). A generalized linear mixed model utilizing Poisson distribution was performed with the surgeon as a random effect. Surgeons performing 1-9 total cases, 10-29 cases, and 30-100 cases had increased total cost of surgery (P < 0.001; P < 0.001; and P<0.001, respectively) compared to high-volume surgeons (> 100 cases). Among all volume cohorts, high-volume surgeons also had the lowest mean supply cost, personnel cost, and operative times, while the opposite was true for the lowest-volume surgeons (1-9 cases). CONCLUSION: It is becoming increasingly important for hospitals to identify modifiable sources of variation in cost. We demonstrate a novel use of TDABC for this purpose. LEVEL OF EVIDENCE: Level-III.

Preoperative Hounsfield Units Predict Pedicle Screw Loosening in Osteoporotic Patients Following Short Segment Lumbar Fusion.

STUDY DESIGN: Retrospective Cohort. OBJECTIVE: (1) To determine if vertebral HU values obtained from preoperative CT predict postoperative outcomes following 1-3 level lumbar fusion and (2) to investigate whether decreased BMD values determined by HU predict cage subsidence and screw loosening. SUMMARY OF BACKGROUND DATA: In light of suboptimal screening for osteoporosis, vertebral computerized tomography(CT) Hounsfield Units(HU), have been investigated as a surrogate for bone mineral density(BMD). METHODS: In this retrospective study, adult patients who underwent 1-3 level posterior lumbar decompression and fusion(PLDF) or transforaminal lumbar interbody and fusion(TLIF) for degenerative disease between the years 2017-2022 were eligible for inclusion. Demographics and surgical characteristics were collected. Outcomes assessed included 90-day readmissions, 90-day complications, revisions, patient reported outcomes(PROMs), cage subsidence, and screw loosening. Osteoporosis was defined as HU of ≤110 on preoperative CT at L1. RESULTS: We assessed 119 patients with a mean age of 59.1, of whom 80.7% were white and 64.7% were nonsmokers. The majority underwent PLDF(63%) compared to TLIF(37%), with an average of 1.63 levels fused. Osteoporosis was diagnosed in 37.8% of the cohort with a mean HU in the osteoporotic group of 88.4 compared to 169 in non-osteoporotic patients. Although older in age, osteoporotic individuals did not exhibit increased 90-day readmissions, complications, or revisions compared to non-osteoporotic patients. A significant increase in the incidence of screw loosening was noted in the osteoporotic group with no differences observed in subsidence rates. On multivariable linear regression osteoporosis was independently associated with less improvement in visual analog scale(VAS) scores for back pain. CONCLUSIONS: Osteoporosis predicts screw loosening and increased back pain. Clinicians should be advised of the importance of preoperative BMD optimization as part of their surgical planning and the utility of vertebral CT HU as a tool for risk stratification. LEVEL OF EVIDENCE: 3.

The impact of robotic assistance for lumbar fusion surgery on 90-day surgical outcomes and 1-year revisions.

Objectives: To evaluate the (1) 90-day surgical outcomes and (2) 1-year revision rate of robotic versus nonrobotic lumbar fusion surgery. Methods: Patients >18 years of age who underwent primary lumbar fusion surgery at our institution were identified and propensity-matched in a 1:1 fashion based on robotic assistance during surgery. Patient demographics, surgical characteristics, and surgical outcomes, including 90-day surgical complications and 1-year revisions, were collected. Multivariable regression analysis was performed. Significance was set to P < 0.05. Results: Four hundred and fifteen patients were identified as having robotic lumbar fusion and were matched to a control group. Bivariant analysis revealed no significant difference in total 90-day surgical complications (P = 0.193) or 1-year revisions (P = 0.178). The operative duration was longer in robotic surgery (287 + 123 vs. 205 + 88.3, P ≤ 0.001). Multivariable analysis revealed that robotic fusion was not a significant predictor of 90-day surgical complications (odds ratio [OR] = 0.76 [0.32-1.67], P = 0.499) or 1-year revisions (OR = 0.58 [0.28-1.18], P = 0.142). Other variables identified as the positive predictors of 1-year revisions included levels fused (OR = 1.26 [1.08-1.48], P = 0.004) and current smokers (OR = 3.51 [1.46-8.15], P = 0.004). Conclusion: Our study suggests that robotic-assisted and nonrobotic-assisted lumbar fusions are associated with a similar risk of 90-day surgical complications and 1-year revision rates; however, robotic surgery does increase time under anesthesia.

Development and psychometric properties of appraisals of post traumatic spinal cord injury health scale in Iran.

STUDY DESIGN: Development and psychometrics study OBJECTIVE: To evaluate the reliability and validity of a new version of Appraisals of Post-Traumatic Spinal Cord Injury Health Scale (APTSCIHS) in the Persian language for persons with spinal cord injury (SCI). SETTING: The persons were selected from National Spinal Cord Injury Registry of Iran (NSCIR-IR) and Brain and Spinal Cord Injury Research center (BASIR). METHOD: This was a mixed sequential exploratory study that performed in two phases. In the qualitative phase, a systematic scoping review and 12 interviews with the participants were done. Finally, items were generated. In the quantitative phase, face, content, construct and convergent validity were assessed to evaluate validity. To evaluate construct validity, a cross-sectional study was conducted on 305 persons with TSCI along with internal consistency and stability assessments. All quantitative data analyses were conducted using SPSS 22 software. RESULTS: The content validity and reliability were indicated by Scale's Content Validity Ratio (S-CVR) = 0.73 and Scale's Content Validity Index (S-CVI) = 0.86, Cronbach's α = 0.9 and the Test re-test reliability using intra-class correlations were (ICC) = 0.97 to 0.98. Exploratory factor analysis determined eight factors which showed more than 52% of the variance. APTSCIHS had a significant and strong correlation with Appraisals of DisAbility Primary and Secondary Scale (ADAPSS) (r = 0.475, P < 0.001). CONCLUSION: Results showed the 36 items APTSCIHS tool had an acceptable validity and reliability in Iran, and it can help health care providers or even administrators improve the quality of the rehabilitation services and quality of life.

Postoperative C5 Palsy after Anterior or Posterior Decompression for Degenerative Cervical Myelopathy: A Subgroup Analysis of the Multicenter, Prospective, Randomized, Phase III, CSM-Protect Clinical Trial.

STUDY DESIGN: Retrospective cohort study of prospectively accrued data. OBJECTIVE: To evaluate a large, prospective, multicentre dataset of surgically-treated DCM cases on the contemporary risk of C5 palsy with surgical approach. SUMMARY OF BACKGROUND DATA: The influence of surgical technique on postoperative C5 palsy after decompression for degenerative cervical myelopathy (DCM) is intensely debated. Comprehensive analyses are needed using contemporary data and accounting for covariates. METHODS: Patients with moderate to severe DCM were prospectively enrolled in the multicenter, randomized CSM-Protect clinical trial and underwent either anterior or posterior decompression between Jan 31, 2012, to May 16, 2017. The primary outcome was the incidence of postoperative C5 palsy, defined as onset of muscle weakness by at least one grade in manual muscle test at the C5 myotome with slight or absent sensory disruption after cervical surgery. Two comparative cohorts were made based on anterior or posterior surgical approach. Multivariate hierarchical mixed-effects logistic regression was used to estimate odds ratios (OR) with 95% confidence intervals (CI) for C5 palsy. RESULTS: A total of 283 patients were included, and 53.4% underwent posterior decompression. The total incidence of postoperative C5 palsy was 7.4% and was significantly higher in patients that underwent posterior decompression compared to anterior decompression (11.26% vs. 3.03%, P=0.008). After multivariable regression, posterior approach was independently associated with greater than four times the likelihood of postoperative C5 palsy (P=0.017). Rates of C5 palsy recovery were comparable between the two surgical approaches. CONCLUSION: The odds of postoperative C5 palsy are significantly higher after posterior decompression compared to anterior decompression for DCM. This may influence surgical decision-making when there is equipoise in deciding between anterior and posterior treatment options for DCM. LEVEL OF EVIDENCE: Therapeutic Level II.

Relating preoperative MCS-12 to microdiscectomy outcomes.

PURPOSE: To determine the impact of poor mental health on patient-reported and surgical outcomes after microdiscectomy. METHODS: Patients ≥ 18 years who underwent a single-level lumbar microdiscectomy from 2014 to 2021 at a single academic institution were retrospectively identified. Patient-reported outcomes (PROMs) were collected at preoperative, three-month, and one-year postoperative time points. PROMs included the Oswestry Disability Index (ODI), Visual Analog Scale Back and Leg (VAS Back and VAS Leg, respectively), and the mental and physical component of the short form-12 survey (MCS and PCS). The minimum clinically important differences (MCID) were employed to compare scores for each PROM. Patients were categorized as having worse mental health or better mental health based on a MCS threshold of 50. RESULTS: Of 210 patients identified, 128 (61%) patients had a preoperative MCS score ≤ 50. There was no difference in 90-day surgical readmissions or spine reoperations within one year. At 3- and 12-month time points, both groups demonstrated improvements in all PROMs (p < 0.05). At three months postoperatively, patients with worse mental health had significantly lower PCS (42.1 vs. 46.4, p = 0.004) and higher ODI (20.5 vs. 13.3, p = 0.006) scores. Lower mental health scores were associated with lower 12-month PCS scores (43.3 vs. 48.8, p < 0.001), but greater improvements in 12-month ODI (- 28.36 vs. - 18.55, p = 0.040). CONCLUSION: While worse preoperative mental health was associated with lower baseline and postoperative PROMs, patients in both groups experienced similar improvements in PROMs. Rates of surgical readmissions and reoperations were similar among patients with varying preoperative mental health status.

Radiology Reports Do Not Accurately Portray the Severity of Cervical Neural Foraminal Stenosis.

STUDY DESIGN: Retrospective study. OBJECTIVE: (1) To compare cervical magnetic resonance imaging (MRI) radiology reports to a validated grading system for cervical foraminal stenosis (FS) and (2) to evaluate whether the severity of cervical neural FS on MRI correlates to motor weakness or patient-reported outcomes. BACKGROUND: Radiology reports of cervical spine MRI are often reviewed to assess the degree of neural FS. However, research looking at the association between these reports and objective MRI findings, as well as clinical symptoms, is lacking. PATIENTS AND METHODS: We retrospectively identified all adult patients undergoing primary 1 or 2-level anterior cervical discectomy and fusion at a single academic center for an indication of cervical radiculopathy. Preoperative MRI was assessed for neural FS severity using the grading system described by Kim and colleagues for each level of fusion, as well as adjacent levels. Neural FS severity was recorded from diagnostic radiologist MRI reports. Motor weakness was defined as an examination grade <4/5 on the final preoperative encounter. Regression analysis was conducted to evaluate whether the degree of FS by either classification was related to patient-reported outcome measure severity. RESULTS: A total of 283 patients were included in the study, and 998 total levels were assessed. There were significant differences between the MRI grading system and the assessment by radio-logists (P< 0.001). In levels with moderate stenosis, 28.9% were classified as having no stenosis by radiology. In levels with severe stenosis, 29.7% were classified as having mild-moderate stenosis or less. Motor weakness was found similarly often in levels of moderate or severe stenosis (6.9% and 9.2%, respectively). On regression analysis, no associations were found between baseline patient-reported outcome measures and stenosis severity assessed by radiologists or MRI grading systems. CONCLUSION: Radiology reports on the severity of cervical neural FS are not consistent with a validated MRI grading system. These radiology reports underestimated the severity of neural foraminal compression and may be inappropriate when used for clinical decision-making. LEVEL OF EVIDENCE: Level III.

Impact of Weekday on Short-term Surgical Outcomes After Lumbar Fusion Surgery.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: The purpose of this study is to investigate whether weekday lumbar spine fusion surgery has an impact on surgical and inpatient physical therapy (PT) outcomes. SUMMARY OF BACKGROUND DATA: Timing of surgery has been implicated as a factor that may impact outcomes after spine surgery. Previous literature suggests that there may be an adverse effect to having surgery on the weekend. METHODS: All patients ≥18 years who underwent primary lumbar spinal fusion from 2014 to 2020 were retrospectively identified. Patients were subdivided into an early subgroup (surgery between Monday and Wednesday) and a late subgroup (surgery between Thursday and Friday). Surgical outcome variables included inpatient complications, 90-day readmissions, and 1-year revisions. PT data from the first inpatient PT session included hours to PT session, AM-PAC Daily Activity or Basic Mobility scores, and total gait trial distance achieved. RESULTS: Of the 1239 patients identified, 839 had surgery between Monday and Wednesday and 400 had surgery between Thursday and Friday. Patients in the later surgery subgroup were more likely to experience a nonsurgical neurologic complication (3.08% vs. 0.86%, P=0.008); however, there was no difference in total complications. Patients in the early surgery subgroup had their first inpatient PT session earlier than patients in the late subgroup (15.7 vs. 18.9 h, P<0.001). However, patients in the late subgroup achieved a farther total gait distance (98.2 vs. 75.4, P=0.011). Late surgery was a significant predictor of more hours of PT (est.=0.256, P=0.016) and longer length of stay (est.=2.277, P=0.001). There were no significant differences in readmission and revision rates. CONCLUSIONS: Patients who undergo surgery later in the week may experience more nonsurgical neurologic complications, longer wait times for inpatient PT appointments, and longer lengths of stay. This analysis showed no adverse effect of later weekday surgery as it relates to total complications, readmissions, and reoperations. LEVEL OF EVIDENCE: Level III.

A Longitudinal Evaluation of Coronavirus Disease 2019 and Its Effects on Spinal Decompressions With or Without Fusion.

STUDY DESIGN: Retrospective cohort. OBJECTIVE: The objectives were to (1) compare the safety of spine surgery before and after the emergence of coronavirus disease 2019 (COVID-19) and (2) determine whether patients with a history of COVID-19 were at increased risk of adverse events. SUMMARY AND BACKGROUND DATA: The COVID-19 pandemic had a tremendous impact on several health care services. In spine surgery, elective cases were canceled and patients received delayed care due to the uncertainty of disease transmission and surgical outcomes. As new coronavirus variants arise, health care systems require guidance on how to provide optimal patient care to all those in need of our services. PATIENTS AND METHODS: A retrospective review of patients undergoing spine surgery between January 1, 2019 and June 30, 2021 was performed. Patients were split into pre-COVID or post-COVID cohorts based on local government guidelines. Inpatient complications, 90-day readmission, and 90-day mortality were compared between groups. Secondary analysis included multiple logistic regression to determine independent predictors of each outcome. RESULTS: A total of 2976 patients were included for analysis with 1701 patients designated as pre-COVID and 1275 as post-COVID. The pre-COVID cohort had fewer patients undergoing revision surgery (16.8% vs 21.9%, P < 0.001) and a lower home discharge rate (84.5% vs 88.2%, P = 0.008). Inpatient complication (9.9% vs 9.2%, P = 0.562), inpatient mortality (0.1% vs 0.2%, P = 0.193), 90-day readmission (3.4% vs 3.2%, P = 0.828), and 90-day mortality rates (0.8% vs 0.8%, P = 0.902) were similar between groups. Patients with positive COVID-19 tests before surgery had similar complication rates (7.7% vs 6.1%, P = 1.000) as those without a positive test documented. CONCLUSIONS: After the emergence of COVID-19, patients undergoing spine surgery had a greater number of medical comorbidities, but similar rates of inpatient complications, readmission, and mortality. Prior COVID-19 infection was not associated with an increased risk of postsurgical complications or mortality. LEVEL OF EVIDENCE: Level III.

Evaluation of perioperative care and drivers of cost in geriatric thoracolumbar trauma.

Introduction: As the population of elderly patients continues to rise, the number of these individuals presenting with thoracolumbar trauma is expected to increase. Research question: To investigate thoracolumbar fusion outcomes for patients with vertebral fractures as stratified by decade. Secondarily, we examined the variability of cost across age groups by identifying drivers of cost of care. Materials and methods: We queried the United States Nationwide Inpatient Sample(NIS) for adult patients undergoing spinal fusion for thoracolumbar fractures between 2012 and 2017. Patients were stratified by decade 60-69(sexagenarians), 70-79(septuagenarians) and 80-89(octogenarians). Bivariable analysis followed by multivariable regression was performed to assess independent predictors of length of stay(LOS), hospital cost, and discharge disposition. Results: A total of 2767 patients were included, of which 46%(N = 1268) were sexagenarians, 36% septuagenarians and 18%(N = 502) octogenarians. Septuagenarians and octogenarians had shorter LOS compared to sexagenarians(ß = -0.88 days; p = 0.012) and(ß = -1.78; p < 0.001), respectively. LOS was reduced with posterior approach(-2.46 days[95% CI: 3.73-1.19]; p < 0.001), while Hispanic patients had longer LOS(+1.97 [95% CI: 0.81-3.13]; p < 0.001). Septuagenarians had lower total charges $12,185.70(p = 0.040), while the decrease in charges in octogenarians was more significant, with a decrease of $26,016.30(p < 0.001) as compared to sexagenarians. Posterior approach was associated with a decrease of $24,337.90 in total charges(p = 0.026). Septuagenarians and octogenarians had 1.72 higher odds(p < 0.001) and 4.16 higher odds(p < 0.001), respectively, of discharge to a skilled nursing facility. Discussion and conclusions: Healthcare utilization in geriatric thoracolumbar trauma is complex. Cost reductions in the acute hospital setting may be offset by unaccounted costs after discharge. Further research into this phenomenon and observed racial/ethnic disparities must be pursued.

In-hospital mortality trends after surgery for traumatic thoracolumbar injury: A national inpatient sample database study.

Introduction: Given the increasing incidence of traumatic thoracolumbar injuries in recent years, studies have sought to investigate potential risk factors for outcomes in these patients. Research question: The aim of this study was to investigate trends and risk factors for in-hospital mortality after fusion for traumatic thoracolumbar injury. Materials and methods: Patients undergoing thoracolumbar fusion after traumatic injury were queried from the National Inpatient Sample (NIS) from 2012 to 2017. Analysis was performed to identify risk factors for inpatient mortality after surgery. Results: Patients in 2017 were on average older (51.0 vs. 48.5, P = 0.004), had more admitting diagnoses (15.5 vs. 10.7, p < 0.001), were less likely to be White (75.8% vs. 81.2%, p = 0.006), were from a ZIP code with a higher median income quartile (Quartile 1: 31.4% vs. 28.6%, p = 0.011), and were more likely to have Medicare as a primary payer (22.9% vs. 30.1%, p < 0.001). Bivariate analysis of demographics and surgical characteristics demonstrated that patients in the in-hospital mortality group (n = 90) were older (70.2 vs. 49.6, p < 0.001), more likely to be male (74.4% vs. 62.8%, p = 0.031), had a great number of admitted diagnoses (21.3 vs. 12.7, p < 0.001), and were more likely to be insured by Medicare (70.0% vs. 27.0%, p < 0.001). Multivariate regression analysis found age (OR 1.06, p < 0.001) and Black race (OR 3.71, p = 0.007) were independently associated with in-hospital mortality. Conclusion: Our study of nationwide, traumatic thoracolumbar fusion procedures from 2012 to 2017 in the NIS database found older, black patients were at increased risk for in-hospital mortality after surgery.

What is the Marginal Cost of Using Robot Assistance or Navigation for Transforaminal Lumbar Interbody Fusion? A Time-Driven Activity-Based Cost Analysis.

BACKGROUND AND OBJECTIVE: Our primary objective was to compare the marginal intraoperative cost of 3 different methods for pedicle screw placement as part of transforaminal lumbar interbody fusions (TLIFs). Specifically, we used time-driven activity-based costing to compare costs between robot-assisted TLIF (RA-TLIF), TLIF with intraoperative navigation (ION-TLIF), and freehand (non-navigated, nonrobotic) TLIF. METHODS: Total cost was divided into direct and indirect costs. We identified all instances of RA-TLIF (n = 20), ION-TLIF (n = 59), and freehand TLIF (n = 233) from 2020 to 2022 at our institution. Software was developed to automate the extraction of all intraoperatively used personnel and material resources from the electronic medical record. Total costs were determined through a combination of direct observation, electronic medical record extraction, and interdepartmental collaboration (business operations, sterile processing, pharmacy, and plant operation departments). Multivariable linear regression analysis was performed to compare costs between TLIF modalities, accounting for patient-specific factors as well as number of levels fused, surgeon, and hospital site. RESULTS: The average total intraoperative cost per case for the RA-TLIF, ION-TLIF, and freehand TLIF cohorts was $24 838 ± $10 748, $15 991 ± $6254, and $14 498 ± $6580, respectively. Regression analysis revealed that RA-TLIF had significantly higher intraoperative cost compared with both ION-TLIF (ß-coefficient: $7383 ± $1575, P < .001) and freehand TLIF (ß-coefficient: $8182 ± $1523, P < .001). These cost differences were primarily driven by supply cost. However, there were no significant differences in intraoperative cost between ION-TLIF and freehand TLIF (P = .32). CONCLUSION: We demonstrate a novel use of time-driven activity-based costing methodology to compare different modalities for executing the same type of lumbar fusion procedure. RA-TLIF entails significantly higher supply cost when compared with other modalities, which explains its association with higher total intraoperative cost. The use of ION, however, does not add extra expense compared with freehand TLIF when accounting for confounders. This might have implications as surgeons and hospitals move toward bundled payments.

Validation of the AO Spine CROST (Clinician Reported Outcome Spine Trauma) in the clinical setting.

PURPOSE: To evaluate feasibility, internal consistency, inter-rater reliability, and prospective validity of AO Spine CROST (Clinician Reported Outcome Spine Trauma) in the clinical setting. METHODS: Patients were included from four trauma centers. Two surgeons with substantial amount of experience in spine trauma care were included from each center. Two separate questionnaires were administered at baseline, 6-months and 1-year: one to surgeons (mainly CROST) and another to patients (AO Spine PROST-Patient Reported Outcome Spine Trauma). Descriptive statistics were used to analyze patient characteristics and feasibility, Cronbach's α for internal consistency. Inter-rater reliability through exact agreement, Kappa statistics and Intraclass Correlation Coefficient (ICC). Prospective analysis, and relationships between CROST and PROST were explored through descriptive statistics and Spearman correlations. RESULTS: In total, 92 patients were included. CROST showed excellent feasibility results. Internal consistency (α = 0.58-0.70) and reliability (ICC = 0.52 and 0.55) were moderate. Mean total scores between surgeons only differed 0.2-0.9 with exact agreement 48.9-57.6%. Exact agreement per CROST item showed good results (73.9-98.9%). Kappa statistics revealed moderate agreement for most CROST items. In the prospective analysis a trend was only seen when no concerns at all were expressed by the surgeon (CROST = 0), and moderate to strong positive Spearman correlations were found between CROST at baseline and the scores at follow-up (rs = 0.41-0.64). Comparing the CROST with PROST showed no specific association, nor any Spearman correlations (rs = -0.33-0.07). CONCLUSIONS: The AO Spine CROST showed moderate validity in a true clinical setting including patients from the daily clinical practice.

Using Oswestry Disability Index as a Preoperative Surgical Eligibility Criterion for Patients Requiring Lumbar Fusion for Degenerative Lumbar Spine Disease.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: To evaluate how preoperative Oswestry Disability Index (ODI) thresholds might affect minimal clinically important difference (MCID) achievement following lumbar fusion. SUMMARY OF BACKGROUND DATA: As payers invest in alternative payment models, some are suggesting threshold cutoffs of patient reported outcomes (PROMs) in reimbursement approvals for orthopedic procedures. The feasibility of this has not been investigated in spine surgery. MATERIALS/METHODS: We included all adult patients undergoing 1-3 level primary lumbar fusion at a single urban tertiary academic center from 2014-2020. ODI was collected preoperatively and one-year postoperatively. We implemented theoretical threshold cutoffs at increments of 10. MCID was set at 14.3. The percent of patients meeting MCID were determined among patients "approved" or "denied" at each threshold. At each threshold, the positive predictive value (PPV) for MCID attainment was calculated. RESULTS: A total 1,368 patients were included and 62.4% (N=364) achieved MCID. As the ODI thresholds increased, a greater percent of patients in each group reached the MCID. At the lowest ODI threshold, 6.58% (N=90) of patients would be denied, rising to 20.2%, 39.5%, 58.4%, 79.9%, and 91.4% at ODI thresholds of 30, 40, 50, 60, and 70, respectively. The PPV increased from 0.072 among patients with ODI>20 to 0.919 at ODI>70. The number of patients denied a clinical improvement in the denied category per patient achieving the MCID increased at each threshold (ODI>20: 1.96; ODI>30: 2.40; ODI>40: 2.75; ODI>50: 3.03; ODI>60: 3.54; ODI>70: 3.75). CONCLUSION: Patients with poorer preoperative ODI are significantly more likely to achieve MCID following lumbar spine fusion at all ODI thresholds. Setting a preoperative ODI threshold for surgical eligibility will restrict access to patients who may benefit from spine fusion, despite ODI>20 demonstrating the lowest predictive value for MCID achievement.

Understanding Decision Making as It Influences Treatment in Thoracolumbar Burst Fractures Without Neurological Deficit: Conceptual Framework and Methodology.

STUDY DESIGN: This paper presents a description of a conceptual framework and methodology that is applicable to the manuscripts that comprise this focus issue. OBJECTIVES: Our goal is to present a conceptual framework which is relied upon to better understand the processes through which surgeons make therapeutic decisions around how to treat thoracolumbar burst fractures (TL) fractures. METHODS: We will describe the methodology used in the AO Spine TL A3/4 Study prospective observational study and how the radiographs collected for this study were utilized to study the relationships between various variables that factor into surgeon decision making. RESULTS: With 22 expert spine trauma surgeons analyzing the acute CT scans of 183 patients with TL fractures we were able to perform pairwise analyses, look at reliability and correlations between responses and develop frequency tables, and regression models to assess the relationships and interactions between variables. We also used machine learning to develop decision trees. CONCLUSIONS: This paper outlines the overall methodological elements that are common to the subsequent papers in this focus issue.

Using Equipoise to Determine the Radiographic Characteristics Leading to Agreement on Best Treatment for Thoracolumbar Burst Fractures Without Neurologic Deficits.

STUDY DESIGN: Retrospective analysis of prospectively collected data. OBJECTIVES: Our goal was to assess radiographic characteristics associated with agreement and disagreement in treatment recommendation in thoracolumbar (TL) burst fractures. METHODS: A panel of 22 AO Spine Knowledge Forum Trauma experts reviewed 183 cases and were asked to: (1) classify the fracture; (2) assess degree of certainty of PLC disruption; (3) assess degree of comminution; and (4) make a treatment recommendation. Equipoise threshold used was 77% (77:23 distribution of uncertainty or 17 vs 5 experts). Two groups were created: consensus vs equipoise. RESULTS: Of the 183 cases reviewed, the experts reached full consensus in only 8 cases (4.4%). Eighty-one cases (44.3%) were included in the agreement group and 102 cases (55.7%) in the equipoise group. A3/A4 fractures were more common in the equipoise group (92.0% vs 83.7%, P < .001). The agreement group had higher degree of certainty of PLC disruption [35.8% (SD 34.2) vs 27.6 (SD 27.3), P < .001] and more common use of the M1 modifier (44.3% vs 38.3%, P < .001). Overall, the degree of comminution was slightly higher in the equipoise group [47.8 (SD 20.5) vs 45.7 (SD 23.4), P < .001]. CONCLUSIONS: The agreement group had a higher degree of certainty of PLC injury and more common use of M1 modifier (more type B fractures). The equipoise group had more A3/A4 type fractures. Future studies are required to identify the role of comminution in decision making as degree of comminution was slightly higher in the equipoise group.