Acute Macrocystic Thoracic Schwannoma: Systematic Review and Illustrative Case Example.

BACKGROUND: Schwannomas are benign peripheral nerve sheath tumors arising from myelinating Schwann cells. Although macrocystic changes are regularly encountered in schwannoma variants such as vestibular nerve tumors, they are exceedingly rare among spinal neoplasms. METHODS: Case report and systematic review of 4 databases (Ovid Medline, PubMed, Science Direct, and SCOPUS) from inception to present. All peer-reviewed publications reporting intradural cystic thoracic schwannoma were included. RESULTS: We identified 8 publications documenting 9 cases of cystic thoracic schwannoma. Four were female, 5 male; median age was 41 years (range, 27-80). Presentations ranged from incidental to pain, sensory changes, lower extremity paresis, or bowel/bladder dysfunction. Characteristic radiographic findings included T1 hypointensity, T2 hyperintensity, and cord effacement or compression. The present case followed a similar pattern: a 52-year-old male presented with worsening bilateral lower extremity weakness, low back pain, and gait dysfunction, worsening over 3 days. Examination also revealed decreased left lower extremity sensation. Imaging identified a well-delineated intradural, extramedullary macrocystic extending over T7-T10. The patient underwent a laminectomy resulting in complete tumor resection and restoration of intact neurologic function. Final pathology confirmed benign cystic schwannoma. CONCLUSIONS: Macrocystic thoracic schwannomas are exceedingly rare and lack a comprehensive scheme for clinical classification of their natural history and pathogenesis. We report the 10th case of such a schwannoma, and the first associated systematic review. Although macrocystic thoracic schwannomas are not frequently encountered, accurate diagnosis and appropriate neurosurgical treatment is critical in these vulnerable patients, given the opportunity for excellent functional outcomes following neurosurgical treatment.

Leiomyogenic Tumor of the Spine: A Systematic Review.

The study cohort consisted of 83 patients with a mean age of 49.55 (SD 13.72) with a female preponderance (60 patients). Here, 32.14% of patients had primary LTS; the remaining were metastases. Clinical presentation included nonspecific back pain (57.83%), weakness (21.69%) and radicular pain (18.07%). History of uterine neoplasia was found in 33.73% of patients. LTS preferentially affected the thoracic spine (51.81%), followed by the lumbar (21.67%) spine. MRI alone was the most common imaging modality (33.33%); in other cases, it was used with CT (22.92%) or X-ray (16.67%); 19.23% of patients had Resection/Fixation, 15.38% had Total en bloc spondylectomy, and 10.26% had Corpectomy. A minority of patients had laminectomy and decompression. Among those with resection, 45.83% had a gross total resection, 29.17% had a subtotal resection, and 16.67% had a near total resection. Immunohistochemistry demonstrated positivity for actin (43.37%), desmin (31.33%), and Ki67 (25.30). At a follow-up of 19.3 months, 61.97% of patients were alive; 26.25% of 80 patients received no additional treatment, 23.75% received combination radiotherapy and chemotherapy, only chemotherapy was given to 20%, and radiotherapy was given to 17.5%. Few (2.5%) had further resection. For an average of 12.50 months, 42.31% had no symptoms, while others had residual (19.23%), other metastasis (15.38%), and pain (7.69%). On follow-up of 29 patients, most (68.97%) had resolved symptoms; 61.97% of the 71 patients followed were alive.

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 Frailty Influences Outcome After Open, But Not Minimally Invasive, Transforaminal Interbody Fusion: A Case Series of 115 Patients With Lumbar Degenerative Disease.

BACKGROUND: For transforaminal lumbar interbody fusion (TLIF), there are equally good open and minimally invasive surgery (MIS) options. OBJECTIVE: To determine if frailty has a differential effect on outcome for open vs MIS TLIF. METHODS: We performed a retrospective review of 115 TLIF surgeries (1-3 levels) for lumbar degenerative disease performed at a single center; 44 MIS transforaminal interbody fusions and 71 open TLIFs were included. All patients had at least a 2-year follow up, and any revision surgery during that time was recorded. The Adult Spinal Deformity Frailty Index (ASD-FI) was used to separate patients into nonfrail (ASD-FI < 0.3) and frail (ASD-FI > 0.3) cohorts. The primary outcome variables were revision surgery and discharge disposition. Univariate analyses were performed to reveal associations in demographic, radiographic, and surgical data with the outcome variables. Multivariate logistic regression was used to assess independent predictors of outcome. RESULTS: Frailty uniquely predicted both reoperation (odds ratio 8.1, 95% CI 2.5-26.1, P = .0005) and discharge to a location other than home (odds ratio 3.9, 95% CI 1.2-12.7, P = .0239). Post hoc analysis indicated that frail patients undergoing open TLIF had a higher revision surgery rate (51.72%) compared with frail patients undergoing MIS-TLIF (16.7%). Nonfrail patients undergoing open and MIS TLIF had a revision surgery rate of 7.5% and 7.7%, respectively. CONCLUSION: Frailty was associated with increased revision rate and increased probability to discharge to a location other than home after open transforaminal interbody fusions, but not MIS transforaminal interbody fusions. These data suggest that patients with high frailty scores may benefit from MIS-TLIF procedures.

Association of telomere length with risk of complications in adult spinal deformity surgery: a pilot study of 43 patients.

OBJECTIVE: Risk stratification is a critical element of surgical planning. Early tools were fairly crude, while newer instruments incorporate disease-specific elements and markers of frailty. It is unknown if discrepancies between chronological and cellular age can guide surgical planning or treatment. Telomeres are DNA-protein complexes that serve an important role in protecting genomic DNA. Their shortening is a consequence of aging and environmental exposures, with well-established associations with diseases of aging and mortality. There are compelling data to suggest that telomere length can provide insight toward overall health. The authors sought to determine potential associations between telomere length and postoperative complications. METHODS: Adults undergoing elective surgery for spinal deformity were prospectively enrolled. Telomere length was measured from preoperative whole blood using quantitative polymerase chain reaction and expressed as the ratio of telomere (T) to single-copy gene (S) abundance (T/S ratio), with higher T/S ratios indicating longer telomere length. Demographic and patient data included age, BMI, and results for the following rating scales: the Adult Spinal Deformity Frailty Index (ASD-FI), Oswestry Disability Index (ODI), Scoliosis Research Society-22r (SRS-22r), American Society of Anesthesiology (ASA) classification, and Charlson Comorbidity Index (CCI). Operative and postoperative complication data (medical or surgical within 90 days) were also collected. RESULTS: Forty-three patients were enrolled, including 31 women (53%), with a mean age of 66 years and a mean BMI of 28.5. The mean number of levels fused was 11, with 21 (48.8%) combined anterior-posterior approaches. Twenty-two patients (51.2%) had a medical or surgical complication. Patients with a postoperative complication had a significantly lower T/S ratio (0.712 vs 0.813, p = 0.008), indicating shorter telomere length, despite a mild difference in age compared with patients without a postoperative complication (68 vs 63 years, p = 0.069). Patients with complications also had higher CCI scores than patients without complications (2.3 vs 3.8, p = 0.004). There were no significant differences in sex, BMI, ASD-FI score, ASA class, preoperative ODI and SRS-22r scores, number of levels fused, or use of three-column osteotomies. In a multivariate model including age, frailty, ASA class, use of an anterior-posterior approach, CCI score, and telomere length, the authors found that short telomere length was significantly associated with postoperative complications. Patients whose telomere length fell in the shortest quartile had the highest risk (OR 18.184, p = 0.030). CONCLUSIONS: Short telomere length was associated with an increased risk of postoperative complications despite only a mild difference in chronological age. Increasing comorbidity scores also trended toward significance. Larger prospective studies are needed; however, these data provide a compelling impetus to investigate the role of biological aging as a component of surgical risk stratification.

Total Hip Arthroplasty in Patients Who Have Respiratory Disease Who use Supplemental Home Oxygen.

BACKGROUND: The purpose of this study is to investigate the association between supplemental home oxygen prior to surgery and both medical and surgical complications after primary elective total hip arthroplasty (THA) in patients who have respiratory disease (RD). METHODS: The Mariner database was used to identify patients who have RD who received primary elective THA from 2010 to 2020. The THA patient cohorts consisted of 20,872 patients who had RD prescribed home oxygen and 69,520 patients who had RD without home oxygen. For patients who had a diagnosis of RD and were prescribed supplemental home oxygen (O2) and those who were not, the rates of postoperative medical and surgical complications, hospital readmissions, and emergency room visits were determined. Reimbursements and lengths of stay were also determined. Logistic regression analyses were utilized to compare both cohorts to matched cohorts without RD, as well as to each other directly. RESULTS: In comparison to the matched control group, the RD with home oxygen group had a significantly higher rate of pneumonia (odds ratio [OR] 4.27, P < .0001), pulmonary embolism (OR 1.81, P < .0001), periprosthetic joint infection (OR 1.21, P < .0001), and periprosthetic fracture (OR 1.81, P = .001). The RD with home oxygen cohort also had a significantly higher incidence of pneumonia (OR 2.16, P < .0001), periprosthetic joint infection (OR 1.38, P < .0001), and periprosthetic fracture (OR 1.24, P = .009) compared to RD patients who did not have home oxygen. CONCLUSION: Supplemental home oxygen use prior to surgery is associated with a significantly higher risk of postoperative medical and surgical complications after elective THA.

Osteopetrosis is Associated With an Increased Risk for Intraoperative Periprosthetic Fracture in Total Hip Arthroplasty but not in Total Knee Arthroplasty.

BACKGROUND: Osteopetrosis is a rare, inherited disorder in which bone remodels to become pathologically dense. There has been a paucity of data evaluating medical and surgical complications following total hip arthroplasty (THA) and total knee arthroplasty (TKA) in this patient population. The objective of this study was to evaluate osteopetrosis as a potential risk factor for medical and surgical complications following THA and TKA. METHODS: Patients who had a diagnosis of osteopetrosis and underwent THA or TKA from 2010 to 2020 were identified in a national database. A total of 534 THA and 972 TKA patients who had osteopetrosis were identified and compared with matched cohorts of 2,670 and 4,860 patients, respectively. The rates of postoperative medical and surgical complications, hospital readmissions, and emergency room visits were calculated. In addition, reimbursements and lengths of stay were determined. Osteopetrosis patients were then compared to a 5:1 matched cohort without osteopetrosis using logistic regression analyses to control for additional confounding factors. RESULTS: The osteopetrosis THA group had a substantially higher incidence of intraoperative periprosthetic fracture compared to the matched cohort (1.12% versus 0.19%, Odds Ratio 5.88, P = .005). Patients who had a history of osteopetrosis were not found to be at a significantly increased risk for other investigated medical or surgical complications compared to matched controls following THA or TKA. CONCLUSION: Patients who had a history of osteopetrosis undergoing elective primary THA are associated with a significantly increased risk for intraoperative periprosthetic fracture. Patients with a history of osteopetrosis undergoing elective primary TKA were not found to be at an increased risk for any of the investigated complications.

A Prospective, Randomized, Controlled Comparison of Adhesive Wound Closure Devices in an Orthopaedic Patient.

INTRODUCTION: The objective of this study was to compare Zip and Clozex with a typical closure using a running 3-0 Prolene suture. METHODS: A prospective, randomized, controlled trial was conducted in patients aged 18 years and older undergoing elective orthopaedic surgical procedures between 2019 and 2021. Patients were randomized to undergo skin closure using a running 3-0 Prolene suture, Zip, or Clozex. The length and location of incision, time to close, surgeon satisfaction, and complications were recorded. The Stony Brook Scar Evaluation Scale (SBSES) was used to assess cosmesis at 2 weeks and 3 months postoperatively. Patient satisfaction and adverse events were also recorded. RESULTS: Thirty-two patients were included in the analysis. Suture closure time was longer than Zip (266 vs 123 seconds; P = 0.02) and Clozex (266 vs 91 seconds; P = 0.005). SBSES scores were greater for Clozex at 2 weeks compared with suture (4.09 vs 2.8; P = 0.005). At 3 months, Clozex maintained greater scores compared with suture (3.82 vs 2.85; P = 0.023) and Zip (3.82 vs 3.0; P = 0.046).No differences were observed in patient satisfaction at any time points. DISCUSSION: Although patient satisfaction was similar across groups, wound closure times, SBSES scores, and total cost favor Clozex compared with Prolene suture or Zip. CLINICALTRIALSGOV REGISTRATION NUMBER: NCT05251064.

Failure in Adult Spinal Deformity Surgery: A Comprehensive Review of Current Rates, Mechanisms, and Prevention Strategies.

STUDY DESIGN: Literature review. OBJECTIVE: The aim of this review is to summarize recent literature on adult spinal deformity (ASD) treatment failure as well as prevention strategies for these failure modes. SUMMARY OF BACKGROUND DATA: There is substantial evidence that ASD surgery can provide significant clinical benefits to patients. The volume of ASD surgery is increasing, and significantly more complex procedures are being performed, especially in the aging population with multiple comorbidities. Although there is potential for significant improvements in pain and disability with ASD surgery, these procedures continue to be associated with major complications and even outright failure. METHODS: A systematic search of the PubMed database was performed for articles relevant to failure after ASD surgery. Institutional review board approval was not needed. RESULTS: Failure and the potential need for revision surgery generally fall into 1 of 4 well-defined phenotypes: clinical failure, radiographic failure, the need for reoperation, and lack of cost-effectiveness. Revision surgery rates remain relatively high, challenging the overall cost-effectiveness of these procedures. CONCLUSION: By consolidating the key evidence regarding failure, further research and innovation may be stimulated with the goal of significantly improving the safety and cost-effectiveness of ASD surgery.

Targeting Accuracy and Clinical Outcomes of Awake versus Asleep Interventional Magnetic Resonance Imaging-Guided Deep Brain Stimulation for Parkinson's Disease: The University of California, San Francisco Experience.

BACKGROUND: Interventional MRI (iMRI)-guided implantation of deep brain stimulator (DBS) leads has been developed to treat patients with Parkinson's disease (PD) without the need for awake testing. OBJECTIVE: Direct comparisons of targeting accuracy and clinical outcomes for awake stereotactic with asleep iMRI-DBS for PD are limited. METHODS: We performed a retrospective review of patients with PD who underwent awake or iMRI-guided DBS surgery targeting the subthalamic nucleus or globus pallidus interna between 2013 and 2019 at our institution. Outcome measures included Unified Parkinson's Disease Rating Scale Part III scores, levodopa equivalent daily dose, radial error between intended and actual lead locations, stimulation parameters, and complications. RESULTS: Of the 218 patients included in the study, the iMRI cohort had smaller radial errors (iMRI: 1.27 ± 0.72 mm, awake: 1.59 ± 0.96 mm, P < .01) and fewer lead passes (iMRI: 1.0 ± 0.16, awake: 1.2 ± 0.41, P < .01). Changes in Unified Parkinson's Disease Rating Scale were similar between modalities, but awake cases had a greater reduction in levodopa equivalent daily dose than iMRI cases ( P < .01), which was attributed to the greater number of awake subthalamic nucleus cases on multivariate analysis. Effective clinical contacts used for stimulation, side effect thresholds, and complication rates were similar between modalities. CONCLUSION: Although iMRI-DBS may result in more accurate lead placement for intended target compared with awake-DBS, clinical outcomes were similar between surgical approaches. Ultimately, patient preference and surgeon experience with a given DBS technique should be the main factors when determining the "best" method for DBS implantation.

Functional Activity After Flatfoot Reconstruction With Lateral Column Lengthening.

BACKGROUND: The objective of this study was to evaluate return to activity following flatfoot reconstruction with lateral column lengthening (LCL) by assessing functional postoperative data and identifying patient characteristics associated with poor function following surgery. METHODS: Consecutive patients that underwent operative flatfoot correction including LCL and other necessary procedures from 2014 to 2019 by 3 fellowship trained foot and ankle orthopedic surgeons were retrospectively administered Foot and Ankle Ability Measure (FAAM) Activities of Daily Living (ADL) and FAAM Sports questionnaires with no preoperative scoring available. Patient demographic factors, comorbidities, and radiographic features were evaluated as predictors of outcome scores to simulate return to activity. Statistical analysis, including student's t-tests and analysis of variance, was performed. RESULTS: A total of 54 patients were included. A body mass index (BMI) of 30 kg/m2 or greater was associated with a lower ADL score (P = .002) and Sports score (P = .002). Preoperative hindfoot valgus of 9° or higher was associated with higher ADL scores (P = .040). Neither age nor any flatfoot radiographic parameters yielded significant differences in functional scores. CONCLUSION: This study demonstrated relatively high average FAAM scores in both the ADL and the sports subscales, consistent with previous studies. This study also identified lower BMI and greater preoperative hindfoot valgus as potential predictors of improved functional outcome following reconstruction. LEVEL OF EVIDENCE: Level III: Retrospective case control.

Neurosurgery Subspecialty Practice During a Pandemic: A Multicenter Analysis of Operative Practice in 7 U.S. Neurosurgery Departments During Coronavirus Disease 2019.

OBJECTIVE: Changes to neurosurgical practices during the coronavirus disease 2019 (COVID-19) pandemic have not been thoroughly analyzed. We report the effects of operative restrictions imposed under variable local COVID-19 infection rates and health care policies using a retrospective multicenter cohort study and highlight shifts in operative volumes and subspecialty practice. METHODS: Seven academic neurosurgery departments' neurosurgical case logs were collected; procedures in April 2020 (COVID-19 surge) and April 2019 (historical control) were analyzed overall and by 6 subspecialties. Patient acuity, surgical scheduling policies, and local surge levels were assessed. RESULTS: Operative volume during the COVID-19 surge decreased 58.5% from the previous year (602 vs. 1449, P = 0.001). COVID-19 infection rates within departments' counties correlated with decreased operative volume (r = 0.695, P = 0.04) and increased patient categorical acuity (P = 0.001). Spine procedure volume decreased by 63.9% (220 vs. 609, P = 0.002), for a significantly smaller proportion of overall practice during the COVID-19 surge (36.5%) versus the control period (42.0%) (P = 0.02). Vascular volume decreased by 39.5% (72 vs. 119, P = 0.01) but increased as a percentage of caseload (8.2% in 2019 vs. 12.0% in 2020, P = 0.04). Neuro-oncology procedure volume decreased by 45.5% (174 vs. 318, P = 0.04) but maintained a consistent proportion of all neurosurgeries (28.9% in 2020 vs. 21.9% in 2019, P = 0.09). Functional neurosurgery volume, which declined by 81.4% (41 vs. 220, P = 0.008), represented only 6.8% of cases during the pandemic versus 15.2% in 2019 (P = 0.02). CONCLUSIONS: Operative restrictions during the COVID-19 surge led to distinct shifts in neurosurgical practice, and local infective burden played a significant role in operative volume and patient acuity.

Use of Supplemental Home Oxygen is Associated With Early Postoperative Complications Following Total Knee Arthroplasty.

BACKGROUND: The objective of this study is to evaluate preoperative supplemental home oxygen use as a potential risk factor for both medical and surgical complications following primary elective total knee arthroplasty (TKA) in patients who have respiratory disease (RD). METHODS: Patients with a diagnosis of RD who underwent elective TKA from 2010 to 2020 were identified using a national database. The rates of postoperative medical and surgical complications, hospital readmissions, and emergency room visits were calculated for RD patients who used supplemental home oxygen and those who did not. Additionally, reimbursements and lengths of stay were determined. Both cohorts were then compared to matched cohorts who did not have RD using logistic regression analyses. RESULTS: A total of 41,418 patients who underwent TKA with RD on home oxygen and 138,635 patients who had RD without home oxygen use were compared with matched cohorts. The RD cohort with home oxygen use had a significantly higher incidence of periprosthetic joint infection (5.78% versus 2.69%, odds ratio [OR] 1.42, P < .0001), pneumonia (3.95% versus 0.69%, OR 4.44, P < .0001), venous thromboembolism (3.17% versus 2.10%, OR 1.12, P = .007), and periprosthetic fracture (0.82% versus 0.34%, OR 1.72, P < .0001) compared to the matched control cohort. Additionally, the RD with home oxygen cohort had a significantly higher incidence of periprosthetic joint infection (5.78% versus 3.77%, OR 1.15, P < .0001), pneumonia (3.95% versus 1.63%, OR 1.99, P < .0001), and several other medical complications compared to RD patients without home oxygen use. CONCLUSION: Preoperative supplemental home oxygen use is associated with significantly increased risk of postoperative surgical and medical complications following elective TKA. This finding can help guide risk assessment and the informed consent process prior to surgery.

Inferior Clinical Outcomes for Patients with Medicaid Insurance After Surgery for Degenerative Lumbar Spondylolisthesis: A Prospective Registry Analysis of 608 Patients.

BACKGROUND: It remains unclear how type of insurance coverage affects long-term, spine-specific patient-reported outcomes (PROs). This study sought to elucidate the impact of insurance on clinical outcomes after lumbar spondylolisthesis surgery. METHODS: The prospective Quality Outcomes Database registry was queried for patients with grade 1 degenerative lumbar spondylolisthesis who underwent single-segment surgery. Twenty-four-month PROs were compared and included Oswestry Disability Index, Numeric Rating Scale (NRS) back pain, NRS leg pain, EuroQol-5D, and North American Spine Society Satisfaction. RESULTS: A total of 608 patients undergoing surgery for grade 1 degenerative lumbar spondylolisthesis (mean age, 62.5 ± 11.5 years and 59.2% women) were selected. Insurance types included private insurance (n = 319; 52.5%), Medicare (n = 235; 38.7%), Medicaid (n = 36; 5.9%), and Veterans Affairs (VA)/government (n = 17; 2.8%). One patient (0.2%) was uninsured and was removed from the analyses. Regardless of insurance status, compared to baseline, all 4 cohorts improved significantly regarding ODI, NRS-BP, NRS-LP, and EQ-5D scores (P < 0.001). In adjusted multivariable analyses, compared with patients with private insurance, Medicaid was associated with worse 24-month postoperative Oswestry Disability Index (ß = 10.2; 95% confidence interval [CI], 3.9-16.5; P = 0.002) and NRS leg pain (ß =1.3; 95% CI, 0.3-2.4; P = 0.02). Medicaid was associated with worse EuroQol-5D scores compared with private insurance (ß = -0.07; 95% CI -0.01 to -0.14; P = 0.03), but not compared with Medicare and VA/government insurance (P > 0.05). Medicaid was associated with lower odds of reaching ODI minimal clinically important difference (odds ratio, 0.2; 95% CI, 0.03-0.7; P = 0.02) compared with VA/government insurance. NRS back pain and North American Spine Society satisfaction did not differ by insurance coverage (P > 0.05). CONCLUSIONS: Despite adjusting for potential confounding variables, Medicaid coverage was independently associated with worse 24-month PROs after lumbar spondylolisthesis surgery compared with other payer types. Although all improved postoperatively, those with Medicaid coverage had relatively inferior improvements.

The Utilization of Postoperative Inpatient Ultrasound for Lower Extremity Deep Venous Thrombosis Following Total Hip Arthroplasty has Decreased Dramatically Over the Past Decade With No Obvious Negative Impact on Patient Care.

BACKGROUND: Surgeons are increasingly performing total hip arthroplasty (THA) in the outpatient setting. Lower lengths of stay (LOS) could result in fewer lower extremity ultrasounds for deep vein thromboses (DVT). The objective of this study was to evaluate the incidence of lower extremity ultrasounds ordered and positive DVT results in the immediate postoperative period. METHODS: All patients undergoing elective primary THA at an academic tertiary care center from January 2010 to February 2020 were included. Primary outcome of interest was incidence of postoperative DVT ultrasounds while inpatient and within 2 weeks following THA. Statistical analysis, including descriptive statistics and significance testing, was performed. RESULTS: A total of 3,665 patients were included, of which, 2.0% (N = 72) of patients received a lower extremity ultrasound while inpatient, with only 2 being positive (2.8%), for an overall positivity rate of 0.05% of the entire cohort. The incidence of postoperative inpatient ultrasounds decreased from 7.0% in 2010 to 0.3% in 2020 (P < .001) whereas, the incidence of ultrasounds at 2 weeks and 2-week positivity rate remained stable. LOS was identified as a risk factor for postoperative inpatient ultrasound (P < .001). CONCLUSIONS: Postoperative ultrasounds to evaluate for DVT are associated with a low yield and appear to be a consequence of reduced LOS in the hospital. Given the stable diagnosis rate of DVT at 2 weeks, our data suggests that the increasing trend toward outpatient arthroplasty will not result in missed opportunities to diagnose postoperative DVTs or lead to adverse outcomes and may provide benefit to patients by eliminating unnecessary testing. LEVEL III EVIDENCE: Retrospective cohort study.

Decision tree-based machine learning analysis of intraoperative vasopressor use to optimize neurological improvement in acute spinal cord injury.

OBJECTIVE: Previous work has shown that maintaining mean arterial pressures (MAPs) between 76 and 104 mm Hg intraoperatively is associated with improved neurological function at discharge in patients with acute spinal cord injury (SCI). However, whether temporary fluctuations in MAPs outside of this range can be tolerated without impairment of recovery is unknown. This retrospective study builds on previous work by implementing machine learning to derive clinically actionable thresholds for intraoperative MAP management guided by neurological outcomes. METHODS: Seventy-four surgically treated patients were retrospectively analyzed as part of a longitudinal study assessing outcomes following SCI. Each patient underwent intraoperative hemodynamic monitoring with recordings at 5-minute intervals for a cumulative 28,594 minutes, resulting in 5718 unique data points for each parameter. The type of vasopressor used, dose, drug-related complications, average intraoperative MAP, and time spent in an extreme MAP range (< 76 mm Hg or > 104 mm Hg) were collected. Outcomes were evaluated by measuring the change in American Spinal Injury Association Impairment Scale (AIS) grade over the course of acute hospitalization. Features most predictive of an improvement in AIS grade were determined statistically by generating random forests with 10,000 iterations. Recursive partitioning was used to establish clinically intuitive thresholds for the top features. RESULTS: At discharge, a significant improvement in AIS grade was noted by an average of 0.71 levels (p = 0.002). The hemodynamic parameters most important in predicting improvement were the amount of time intraoperative MAPs were in extreme ranges and the average intraoperative MAP. Patients with average intraoperative MAPs between 80 and 96 mm Hg throughout surgery had improved AIS grades at discharge. All patients with average intraoperative MAP > 96.3 mm Hg had no improvement. A threshold of 93 minutes spent in an extreme MAP range was identified after which the chance of neurological improvement significantly declined. Finally, the use of dopamine as compared to norepinephrine was associated with higher rates of significant cardiovascular complications (50% vs 25%, p < 0.001). CONCLUSIONS: An average intraoperative MAP value between 80 and 96 mm Hg was associated with improved outcome, corroborating previous results and supporting the clinical verifiability of the model. Additionally, an accumulated time of 93 minutes or longer outside of the MAP range of 76-104 mm Hg is associated with worse neurological function at discharge among patients undergoing emergency surgical intervention for acute SCI.

Do social determinants of health impact access to neurosurgical care in the United States? A workforce perspective.

OBJECTIVE: This study attempts to use neurosurgical workforce distribution to uncover the social determinants of health that are associated with disparate access to neurosurgical care. METHODS: Data were compiled from public sources and aggregated at the county level. Socioeconomic data were provided by the Brookings Institute. Racial and ethnicity data were gathered from the Centers for Disease Control and Prevention Wide-ranging Online Data for Epidemiologic Research. Physician density was retrieved from the Health Resources and Services Administration Area Health Resources Files. Catchment areas were constructed based on the 628 counties with neurosurgical coverage, with counties lacking neurosurgical coverage being integrated with the nearest covered county based on distances from the National Bureau of Economic Research's County Distance Database. Catchment areas form a mutually exclusive and collectively exhaustive breakdown of the entire US population and licensed neurosurgeons. Socioeconomic factors, race, and ethnicity were chosen as independent variables for analysis. Characteristics for each catchment area were calculated as the population-weighted average across all contained counties. Linear regression analysis modeled two outcomes of interest: neurosurgeon density per capita and average distance to neurosurgical care. Coefficient estimates (CEs) and 95% confidence intervals were calculated and scaled by 1 SD to allow for comparison between variables. RESULTS: Catchment areas with higher poverty (CE = 0.64, 95% CI 0.34-0.93) and higher prime age employment (CE = 0.58, 95% CI 0.40-0.76) were significantly associated with greater neurosurgeon density. Among categories of race and ethnicity, catchment areas with higher proportions of Black residents (CE = 0.21, 95% CI 0.06-0.35) were associated with greater neurosurgeon density. Meanwhile, catchment areas with higher proportions of Hispanic residents displayed lower neurosurgeon density (CE = -0.17, 95% CI -0.30 to -0.03). Residents of catchment areas with higher housing vacancy rates (CE = 2.37, 95% CI 1.31-3.43), higher proportions of Native American residents (CE = 4.97, 95% CI 3.99-5.95), and higher proportions of Hispanic residents (CE = 2.31, 95% CI 1.26-3.37) must travel farther, on average, to receive neurosurgical care, whereas people living in areas with a lower income (CE = -2.28, 95% CI -4.48 to -0.09) or higher proportion of Black residents (CE = -3.81, 95% CI -4.93 to -2.68) travel a shorter distance. CONCLUSIONS: Multiple factors demonstrate a significant correlation with neurosurgical workforce distribution in the US, most notably with Hispanic and Native American populations being associated with greater distances to care. Additionally, higher proportions of Hispanic residents correlated with fewer neurosurgeons per capita. These findings highlight the interwoven associations among socioeconomics, race, ethnicity, and access to neurosurgical care nationwide.

Use of Topical Vancomycin Powder to Reduce Surgical Site Infections after Deep Brain Stimulation Surgery: UCSF Experience and Meta-Analysis.

OBJECTIVE: Surgical site infection (SSI) is the most common serious complication of deep brain stimulation (DBS) implantation surgery. Here, we report a single-surgeon experience on the efficacy of topical, intrawound vancomycin powder (VP) in reducing SSI for DBS surgery and present the first systematic review and meta-analysis examining the effect of topical vancomycin on SSI in patients after DBS surgery. METHODS: For the retrospective review, all unique patients undergoing DBS surgery at UCSF for new hardware implantation or internal pulse generator (IPG) replacement by a single surgeon from September 2013 to March 2019, with at least 1 year of follow-up data, were included. For the meta-analysis, we included all primary studies that compared SSIs with and without application of topical vancomycin in DBS surgeries. RESULTS: 368 unique patients met inclusion criteria; 195 patients received topical VP (VP group) and 173 did not (control). 99/195 patients in the VP group underwent new DBS implantation and 96/195 had IPG replacement. 71/173 patients in the control group had new DBS implantation and 102/173 had IPG replacement. There were 10 total cases of SSI: 4 patients from the VP group (3 new implants and 1 IPG replacement) and 6 patients from the control group (3 new implants and 3 IPG replacements), resulting in SSI rates of 2.1 and 3.5%, respectively (p value = 0.337). Including our retrospective analysis, 6 studies met inclusion criteria for the systematic review and meta-analysis. In the 4 studies that examined primary DBS implants, 479 total patients received topical VP and 436 did not; mean odds ratio for SSI with topical vancomycin was 0.802 (95% confidence interval [CI] 0.175-3.678). Across the 5 studies that examined IPG implantations or replacements, 606 total patients received topical VP while 1,173 patients did not; mean odds ratio for SSI with topical vancomycin was 0.492 (95% CI 0.164-1.475). In either case, topical VP application did not significantly decrease risk of SSI. CONCLUSION: Surgical infections after DBS surgery are uncommon events, with studies demonstrating mixed results on whether topical vancomycin reduces this risk. Our single-institution retrospective analysis and systematic review of prior studies both demonstrated no significant SSI rate reduction with topical VP. This is likely due to low baseline SSI rates, resulting in a small effect size for prevention. Given the cost-effectiveness, simplicity, and low risk, topical, intrawound VP remains a treatment option to further reduce risk of SSI, particularly in settings with higher baseline infection rates.

Epidural Spinal Electrogram Provides Direct Spinal Recordings in Awake Human Participants.

Little is known about the electrophysiological activity of the spinal cord during voluntary movement control in humans. We present a novel method for recording electrophysiological activity from the human spinal cord using implanted epidural electrodes during naturalistic movements including overground walking. Spinal electrograms (SEGs) were recorded from epidural electrodes implanted as part of a test trial for patients with chronic pain undergoing evaluation for spinal cord stimulation. Externalized ends of the epidural leads were connected to an external amplifier to capture SEGs. Electromyographic and accelerometry data from the upper and lower extremities were collected using wireless sensors and synchronized to the SEG data. Patients were instructed to perform various arm and leg movements while SEG and kinematic data were collected. This study proves the safety and feasibility of performing epidural spinal recordings from human subjects performing movement tasks.