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.

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.

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.

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

OBJECTIVE: Determine if herniation morphology based on the Michigan State University (MSU) Classification is associated with differences in (1) patient-reported outcome measures (PROMs) or (2) surgical outcomes after a microdiscectomy. METHODS: Adult patients undergoing single-level microdiscectomy between 2014 - 2021 were identified. Demographics and surgical characteristics were collected through a query search and manual chart review. The MSU 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. PROMs were collected at preoperative, three-month, and one-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 PCS at baseline. On bivariate and multivariable logistic regression analysis, extrusion grade >1 was a significant independent predictor of greater improvement in PCS at three months (estimate=7.957; CI: 4.443 - 11.471, p<0.001), but not at one 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 VAS leg and back, ODI, and MCS at three and twelve months was unrelated to laterality or depth of disc herniation.

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.

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.

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.

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.

Does operative level impact dysphagia severity following anterior cervical discectomy and fusion? a multicenter prospective analysis.

STUDY DESIGN: Prospective multi-center cohort study. OBJECTIVE: To explore the association between operative level and postoperative dysphagia after anterior cervical discectomy and fusion (ACDF). SUMMARY OF BACKGROUND DATA: Dysphagia is common following ACDF and has several risk factors including soft tissue edema. The degree of prevertebral soft tissue edema varies based upon the operative cervical level. However, the operative level has not been evaluated as a source of postoperative dysphagia. METHODS: Adult patients undergoing elective ACDF were prospectively enrolled at three academic centers. Dysphagia was assessed using the Bazaz questionnaire, Dysphagia Short Questionnaire (DSQ), and Eating Assessment Tool-10 (EAT-10) preoperatively and at 2, 6, 12, and 24-weeks postoperatively. Patients were grouped based on inclusion of specific surgical levels in the fusion construct. Multivariable regression analyses were performed evaluating the independent effects of number of surgical levels and inclusion of each particular level on dysphagia symptoms. RESULTS: A total of 130 patients were included. Overall, 24 (18.5%) patients had persistent postoperative dysphagia at 24 weeks and were older, female, and less likely to be drink alcohol. There was no difference in operative duration or dexamethasone administration. Patients with persistent dysphagia were significantly more likely to have C4-C5 included in the fusion construct (62.5% vs. 34.9%, P=0.024) but there were no differences based on inclusion of other levels. On multivariable regression, inclusion of C3-C4 or C6-C7 were associated with more severe EAT-10 (ß:9.56, P=0.016 and ß:8.15, P=0.040) and DSQ (ß:4.44, P=0.023 and (ß:4.27, P=0.030) at 6 weeks. At 12-weeks, C3-C4 fusion was also independently associated with more severe dysphagia (EAT-10 ß:4.74, P=0.024). CONCLUSION: The location of prevertebral soft tissue swelling may impact the duration and severity of patient-reported dysphagia outcomes at up to 24 weeks postoperatively. In particular, inclusion of C3-C4 and C4-C5 into the fusion may be associated with dysphagia severity.

The Effect of Muscle Quality on Outcomes after Microdiscectomy.

OBJECTIVES: To investigate the relationship between muscle quality and 1) patient-reported outcomes and 2) surgical outcomes after lumbar microdiscectomy surgery. METHODS: Adult patients (≥18 years) who underwent lumbar microdiscectomy from 2014 to 2021 at a single academic institution were identified. Outcomes were collected during the preoperative, 3-month, 6-month, and 1-year postoperative periods. Those included were 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). Muscle quality was determined by 2 systems: the normalized total psoas area (NTPA) and a paralumbar-based grading system. Surgical outcomes including 90-day surgical readmissions and 1-year reoperations were also collected. RESULTS: Of the 218 patients identified, 150 had good paralumbar muscle quality and 165 had good psoas muscle quality. Bivariant analysis demonstrated no difference between groups regarding surgical outcomes (P > 0.05). Multivariable analysis demonstrated that better paralumbar muscle quality was not associated with any consistent changes in patient reported outcomes. Higher NTPA was associated with improved PCS at 6 months (est. = 6.703, [95% CI: 0.759-12.646], P = 0.030) and 12 months (est. = 6.625, [95% CI: 0.845-12.405], P = 0.027). There was no association between muscle quality and surgical readmissions or reoperations. CONCLUSIONS: Our analysis demonstrated that higher psoas muscle quality was associated with greater physical improvement postoperatively. Muscle quality did not affect surgical readmissions or reoperations. Additional studies are needed for further assessment of the implications of muscle quality on postoperative outcomes.

The Impact of Socioeconomic Status on the Presence of Advance Care Planning Documents in Patients With Acute Cervical Spinal Cord Injury.

INTRODUCTION: Patients presenting with spinal cord injury (SCI) often times have notable deficits or polytrauma and may require urgent decision making for early management. However, their presentation may affect decision-making ability. Although advance care planning (ACP) may help guide spine surgeons as to patient preferences, the rate at which they are available and disparities in ACP completion are still not understood. The objective of this study was to evaluate disparities in the completion of ACP among patients with acute SCI. METHODS: All patients presenting with cervical SCI to the emergency department at an urban, tertiary level I trauma center from 2010 to 2021 were identified from a prospective database of all consults evaluated by the spine service. Each patient's medical record was reviewed to assess for the presence of ACP documents such as living will, power of attorney, or advance directive. Community-level socioeconomic status was assessed using the Distressed Communities Index. Bivariable and multivariable analyses were performed. RESULTS: We identified 424 patients: 104 (24.5%) of whom had ACP. Patients with ACP were older (64.8 versus 56.5 years, P = 0.001), more likely White (78.8% versus 71.9%, P = 0.057), and present with ASIA Impairment Scale grade A SCI (21.2% versus 12.8%, P = 0.054), although the latter two did not reach statistical significance. On multivariable logistic regression, patients residing in at-risk communities were significantly less likely to have ACP documents compared with those in prosperous communities (odds ratio [OR]: 0.29, P = 0.03). Although patients living in distressed communities were less likely to complete ACP compared with those in prosperous communities (OR 0.50, P = 0.066), this did not meet statistical significance. Female patients were also less likely to have ACP (OR: 0.43, P = 0.005). CONCLUSION: Female patients and those from at-risk communities are markedly less likely to complete ACP. Attention to possible disparities during admission and ACP discussions may help ensure that patients of all backgrounds have treatment goals documented.

Significance of Facet Fluid Index in Anterior Cervical Degenerative Spondylolisthesis.

STUDY DESIGN: Retrospective cohort study. PURPOSE: To correlate cervical facet fluid characteristics to radiographic spondylolisthesis, determine if facet fluid is associated with instability in cervical degenerative spondylolisthesis, and examine whether vertebral levels with certain facet fluid characteristics and spondylolisthesis are more likely to be operated on. OVERVIEW OF LITERATURE: The relationship between facet fluid and lumbar spondylolisthesis is well-documented; however, there is a paucity of literature investigating facet fluid in degenerative cervical spondylolisthesis. METHODS: Patients diagnosed with cervical degenerative spondylolisthesis were identified from a hospital's medical records. Demographic and surgical characteristics were collected through a structured query language search and manual chart review. Radiographic measurements were made on preoperative MRIs for all vertebral levels diagnosed with spondylolisthesis and adjacent undiagnosed levels between C3 and C6. The facet fluid index was calculated by dividing the facet fluid measurement by the width of the facet. Bivariate analysis was conducted to compare facet characteristics based on radiographic spondylolisthesis and spondylolisthesis stability. RESULTS: We included 154 patients, for whom 149 levels were classified as having spondylolisthesis and 206 levels did not. The average facet fluid index was significantly higher in patients with spondylolisthesis (0.26±0.07 vs. 0.23±0.08, p <0.001). In addition, both fluid width and facet width were significantly larger in patients with spondylolisthesis (p <0.001 each). Cervical levels in the fusion construct demonstrated a greater facet fluid index and were more likely to have unstable spondylolisthesis than stable spondylolisthesis (p <0.001 each). CONCLUSIONS: Facet fluid index is associated with cervical spondylolisthesis and an increased facet size and fluid width are associated with unstable spondylolisthesis. While cervical spondylolisthesis continues to be an inconclusive finding, vertebral levels with spondylolisthesis, especially the unstable ones, were more likely to be included in the fusion procedure than those without spondylolisthesis.

A new perspective on intervertebral disc calcification-from bench to bedside.

Disc degeneration primarily contributes to chronic low back and neck pain. Consequently, there is an urgent need to understand the spectrum of disc degeneration phenotypes such as fibrosis, ectopic calcification, herniation, or mixed phenotypes. Amongst these phenotypes, disc calcification is the least studied. Ectopic calcification, by definition, is the pathological mineralization of soft tissues, widely studied in the context of conditions that afflict vasculature, skin, and cartilage. Clinically, disc calcification is associated with poor surgical outcomes and back pain refractory to conservative treatment. It is frequently seen as a consequence of disc aging and progressive degeneration but exhibits unique molecular and morphological characteristics: hypertrophic chondrocyte-like cell differentiation; TNAP, ENPP1, and ANK upregulation; cell death; altered Pi and PPi homeostasis; and local inflammation. Recent studies in mouse models have provided a better understanding of the mechanisms underlying this phenotype. It is essential to recognize that the presentation and nature of mineralization differ between AF, NP, and EP compartments. Moreover, the combination of anatomic location, genetics, and environmental stressors, such as aging or trauma, govern the predisposition to calcification. Lastly, the systemic regulation of calcium and Pi metabolism is less important than the local activity of PPi modulated by the ANK-ENPP1 axis, along with disc cell death and differentiation status. While there is limited understanding of this phenotype, understanding the molecular pathways governing local intervertebral disc calcification may lead to developing disease-modifying drugs and better clinical management of degeneration-related pathologies.

Implementation of a Private Payer Bundled Payment Model While Maintaining High-Value Lumbar Spinal Fusion.

STUDY DESIGN: Retrospective single-institution cohort. OBJECTIVE: To evaluate the implementation of a commercial bundled payment model in patients undergoing lumbar spinal fusion. SUMMARY OF BACKGROUND DATA: BPCI-A caused significant losses for many physician practices, prompting private payers to establish their own bundled payment models. The feasibility of these private bundles has yet to be evaluated in spine fusion. METHODS: Patients undergoing lumbar fusion from October to December 2018 in BPCI-A before our institution's departure were included for BPCI-A analysis. Private bundle data was collected from 2018 to 2020. Analysis of the transition was conducted among Medicare-aged beneficiaries. Private bundles were grouped by calendar year (Y1, Y2, Y3). Stepwise multivariate linear regression was performed to measure independent predictors of net deficit. RESULTS: The net surplus was the lowest in Y1 ($2,395, P =0.03) but did not differ between our final year in BPCI-A and subsequent years in private bundles (all, P >0.05). AIR and SNF patient discharges decreased significantly in all private bundle years compared with BPCI. Readmissions fell from 10.7% (N=37) in BPCI-A to 4.4% (N=6) in Y2 and 4.5% (N=3) Y3 of private bundles ( P <0.001). Being in Y2 or Y3 was independently associated with a net surplus in comparison to the Y1 (ß: $11,728, P =0.001; ß: $11,643, P =0.002). Postoperatively, length of stay in days (ß: $-2,982, P <0.001), any readmission (ß: -$18,825, P =0.001), and discharge to AIR (ß: $-61,256, P <0.001) or SNF (ß: $-10,497, P =0.058) were all associated with a net deficit. CONCLUSIONS: Nongovernmental bundled payment models can be successfully implemented in lumbar spinal fusion patients. Constant price adjustment is necessary so bundled payments remain financially beneficial to both parties and systems overcome early losses. Private insurers who have more competition than the government may be more willing to provide mutually beneficial situations where cost is reduced for payers and health systems. LEVEL OF EVIDENCE: 3.

Subfascial Lumbar Spine Drain Output Does Not Affect Outcomes After Incidental Durotomies in Elective Spine Surgery.

OBJECTIVE: Postoperative drains have long been regarded as a preventive measure to mitigate the risks of complications such as neurological impairment by reducing fluid accumulation following spine surgery. Our study aims to contribute to the existing body of knowledge by examining the effects of postoperative drain output on the 90-day postoperative outcomes for patients who experienced an incidental durotomy after lumbar decompression procedures, with or without fusion. METHODS: All patients aged ≥18 years with an incidental durotomy from spinal decompression with or without fusion surgery between 2017 and 2021 were retrospectively identified. The patient demographics, surgical characteristics, method of dural tear repair (DuraSeal, suture, and/or DuraGen), surgical outcomes, and drain data were collected via medical record review. Patients were grouped by readmission status and final 8-hour drain output. Those with a final 8-hour drain output of ≥40 mL were included in the high drain output (HDO) group and those with <40 mL were in the low drain output (LDO) group. RESULTS: There were no statistically significant differences in preoperative patient demographics, surgical characteristics, method of dural tear repair, length of stay (HDO, 4.02 ± 1.90 days; vs. LDO, 4.26 ± 2.10 days; P = 0.269), hospital readmissions (HDO, 10.6%; vs. LDO, 7.96%; P = 0.744), or occurrence of reoperation during readmission (HDO, 6.06%; vs. LDO, 2.65%; P = 0.5944) between the 2 groups. CONCLUSIONS: For patients undergoing primary lumbar decompression with or without fusion and experiencing an incidental durotomy, no significant association was found between the drain output and 90-day patient outcomes. Adequate fascial closure and the absence of symptoms may be satisfactory criteria for standard patient discharge regardless of drain output.