Cervical Spine Fusion Surgery Research Articles

Physical and Psychological Impact of Scar Cosmesis After Cervical Spine Fusion Surgery

IntroductionPatients' and surgeons' perceptions of cutaneous scarring can vary, causing unpleasant physical and psychological outcomes. This study aims to bridge the current scientific literature gap and understand the impact of patient-perceived scar cosmesis after anterior and posterior cervical spine surgery. MethodsRetrospective review of patients ≥18 years old who underwent anterior or posterior cervical spine surgery from 2017 to 2022 at a large, urban academic group. To select patients with adequate time for surgical scar maturation, only patients who were greater than six months post-surgery were included. The SCAR-Q survey, a surgical scar assessment tool, was administered to patients to assess patient perceptions of scar symptomatology, appearance, and psychosocial impact. Scores range from 0 to 100, with 100 as the best outcome. An additional 5-item Likert scale question was administered to assess overall surgical satisfaction. ResultsAll 854 respondents who completed the survey were stratified into two groups“Unsatisfied vs Satisfied.” Patients who were “unsatisfied” with their surgery had the lowest outcome scores for SCAR-Q appearance, symptom, and psychosocial scores than those who were “satisfied” (p<0.001). Females had significantly higher/“more favorable” responses for SCAR-Q Appearance (77.5 vs. 82.8 p<0.001) and Psychosocial (87.4 vs. 94.3 p<0.001) scores compared to males. Regression analysis performed for each component score showed that increases in all three component scores were significant in patients in the satisfied group. ConclusionsOur study demonstrates that cervical spine surgery patients unsatisfied with their surgical outcome have lower scar-related scores, highlighting the impact of cosmetic closure and appearance.

Postoperative opioid consumption patterns diverge between propensity matched patients undergoing traumatic and elective cervical spine fusion

BACKGROUND CONTEXTProlonged opioid therapy following spine surgery is an ongoing postoperative concern. While prior studies have investigated postoperative opioid use patterns in the elective cervical surgery patient population, to our knowledge, opioid use patterns in patients undergoing surgery for traumatic cervical spine injuries have not been elucidated. PURPOSEThe purpose of this study was to compare opioid use and prescription patterns in the postoperative pain management of patients undergoing traumatic and elective cervical spine fusion surgery. STUDY DESIGNRetrospective cohort study. PATIENT SAMPLEAdult patients with traumatic cervical injuries who underwent primary anterior cervical discectomy and fusion (ACDF) or posterior cervical decompression and fusion (PCDF) during their initial hospital admission. The propensity matched, control group consisted of adult elective cervical fusion patients who underwent primary ACDF or PCDF. OUTCOME MEASURESDemographic data, surgical characteristics, spinal disease diagnosis, location of cervical injury, procedure type, operative levels fused, and Prescription Drug Monitoring Program (PDMP) data. PDMP data included the number of opioid prescriptions filled, preoperative opioid use, postoperative opioid use, and use of perioperative benzodiazepines, muscle relaxants, or gabapentin. Opioid consumption data was collected in morphine milligram equivalents (MME) and standardized per day. METHODSA 1:1 propensity match was performed to match traumatic injury patients undergoing cervical fusion surgery with elective cervical fusion patients. Traumatic injury patients were matched based on age, sex, CCI, procedure type, and cervical levels fused. Pre- and postoperative opioid, benzodiazepine, muscle relaxant, and gabapentin use were assessed for the traumatic injury and elective patients. T- or Mann-Whitney U tests were used to compare continuous data and Chi-Squared or Fisher's Exact were used to compare categorical data. Multivariate stepwise regression using MME per day 0 – 30 days following surgery as the dependent outcome was performed to further evaluate associations with postoperative opioid use. RESULTSA total of 48 patients underwent fusion surgery for a traumatic cervical spine injury and 48 elective cervical fusion with complete PDMP data were assessed. Elective patients were found to fill more prescriptions (3.19 vs 0.65, p=.023) and take more morphine milligram equivalents (MME) per day (0.60 vs 0.04, p=.014) within 1 year prior to surgery in comparison to traumatic patients. Elective patients were also more likely to use opioids (29.2% vs 10.4%, p=.040) and take more MMEs per day (0.70 vs 0.05, p=.004) within 30 days prior to surgery. Within 30 days postoperatively, elective patients used opioids more frequently (89.6% vs 52.1%, p<.001) and took more MMEs per day (3.73 vs 1.71, p<.001) than traumatic injury patients. Multivariate stepwise regression demonstrated preoperative opioid use (Estimate: 1.87, p=.013) to be correlated with higher postoperative MME per day within 30 days of surgery. Surgery after traumatic injury was correlated with lower postoperative MME use per day within 30 days of surgery (Estimate: −1.63 p=.022). CONCLUSIONCervical fusion patients with a history of traumatic spine injury consume fewer opioids in the early postoperative period in comparison to elective cervical fusion patients, however both cohorts consumed a similar amount after the initial 30-day postoperative period. Preoperative opioid use was also a risk factor for higher consumption in the short-term postoperative period. These results may aid physicians in further understanding patients’ postoperative care needs based on presenting injury characteristics and highlights the need for enhanced follow-up care for traumatic cervical spine injury patients after fusion surgery.

Characteristics and Outcomes of Patients Treated with Cervical Spine Fusion at High Volume Hospitals

High volume (HV) has been associated with improved outcomes in various neurosurgical procedures. The objective of this study was to explore the regional distribution of HV spine centers for cervical spine fusion and compare characteristics and outcomes for patients treated at HV centers versus lower volume centers. The National Inpatient Sample database 2016-2020 was queried for patients undergoing cervical spine fusion for degenerative pathology. HV was defined as case-loads greater than 2 standard deviations above the mean. Patient characteristics, procedures, and outcomes were compared. Of 3895 hospitals performing cervical spine fusion for degenerative pathology, 28 (0.76%) were HV. The Mid-Atlantic and West South Central regions had the highest number of HV hospitals. HV hospitals were more likely to perform open anterior fusion surgeries (P<0.01). Patients treated at HV hospitals were less likely to have severe symptomatology or comorbidities (P<0.01 for all). When controlling for severity and demographics on multivariate analysis, HV centers had higher odds of length of stay ≤1day, favorable discharge, and decreased total charges. Patients who underwent cervical spine fusion surgery at HV hospitals were less complex and had increased odds of length of stay ≤1, favorable discharge, and total charges in the lower 25th percentile than patients treated at non-HV hospitals. Physician comfort, patient selection, institutional infrastructure, and geographic characteristics likely play a role.

174 Developing Mixed-Effects Models to Optimize Prediction of Postoperative Outcomes in a Modern Sample of Over 450,000 Patients Undergoing Elective Cervical Spine Fusion Surgery

INTRODUCTION: Cervical spine decompression and fusion surgery is commonly used to treat degenerative cervical spine pathologies.However, there is a paucity of high-quality data defining the optimal comorbidity indices specifically in patients undergoing cervical spine fusion surgery. METHODS: Using data from 2016–2019, we queried the Nationwide Readmissions Database (NRD) to identify individuals who had received cervical spine fusion surgery. The Johns Hopkins Adjusted Clinical Groups (JHACG) frailty-defining indicator was used to assess patient frailty. To measure the level of comorbidity, Elixhauser Comorbidity Index (ECI) scores were queried. ROC curves were developed utilizing comorbidity indices as predictor variables for pertinent complications such as death, non-routine discharge, top-quartile cost, top-quartile length of stay (LOS), and one-year readmission. RESULTS: A total of 453,717 patients were eligible for analysis. Non-routine discharges occurred in 93,961 (20.7%) patients. The mean adjusted all-payer cost for the procedure was $22,573.14 ± $18,274.86 (Top Quartile: $26,775.80) and the mean LOS was 2.7 days ± 4.4 days (Top Quartile: 4.7 days). After surgery, there were 703 (0.15%) mortalities and 58,254 (12.8%) readmissions within one year post-operatively. Models using Frailty+ECI as the primary predictor consistently outperformed the ECI only model with statistically significant p-values, as determined by comparing respective AUCs, for most of the complications assessed. Cost and mortality were the only outcomes for which this was not the case, as Frailty outperformed both ECI and Frailty+ECI in cost (p &lt; 0.0001 for all) and Frailty+ECI preformed as well as ECI alone in mortality (p = 0.10). CONCLUSIONS: Our data suggests that Frailty+ECI may most accurately predict clinical outcomes in patients receiving cervical spine surgery. These models may be used to identify high risk populations and patients who may necessitate greater resource utilization.

Reliable Prediction of Discharge Disposition Following Cervical Spine Surgery With Ensemble Machine Learning and Validation on a National Cohort.

A retrospective cohort study. The purpose of this study is to develop a machine learning algorithm to predict nonhome discharge after cervical spine surgery that is validated and usable on a national scale to ensure generalizability and elucidate candidate drivers for prediction. Excessive length of hospital stay can be attributed to delays in postoperative referrals to intermediate care rehabilitation centers or skilled nursing facilities. Accurate preoperative prediction of patients who may require access to these resources can facilitate a more efficient referral and discharge process, thereby reducing hospital and patient costs in addition to minimizing the risk of hospital-acquired complications. Electronic medical records were retrospectively reviewed from a single-center data warehouse (SCDW) to identify patients undergoing cervical spine surgeries between 2008 and 2019 for machine learning algorithm development and internal validation. The National Inpatient Sample (NIS) database was queried to identify cervical spine fusion surgeries between 2009 and 2017 for external validation of algorithm performance. Gradient-boosted trees were constructed to predict nonhome discharge across patient cohorts. The area under the receiver operating characteristic curve (AUROC) was used to measure model performance. SHAP values were used to identify nonlinear risk factors for nonhome discharge and to interpret algorithm predictions. A total of 3523 cases of cervical spine fusion surgeries were included from the SCDW data set, and 311,582 cases were isolated from NIS. The model demonstrated robust prediction of nonhome discharge across all cohorts, achieving an area under the receiver operating characteristic curve of 0.87 (SD=0.01) on both the SCDW and nationwide NIS test sets. Anterior approach only, age, elective admission status, Medicare insurance status, and total Elixhauser Comorbidity Index score were the most important predictors of discharge destination. Machine learning algorithms reliably predict nonhome discharge across single-center and national cohorts and identify preoperative features of importance following cervical spine fusion surgery.

Clinical and Radiological Changes at the Adjacent Segments Following Cervical Spine Surgery: A Retrospective Study

Background and Aim: Adjacent segment disease (ASD), radiological and clinical, is observed in many of the patients who undergo cervical inter-body fusion with/without graft, and with/without plating. This study aims to evaluate the proportion of ASD among patients who underwent cervical spine fusion surgery, to study the severity of degenerative radiographic findings at adjacent levels, and to determine sites and patterns of ASD. Methods and Materials/Patients: A descriptive study was performed on patients who underwent a previous cervical arthrodesis procedure in the last 2-5 years and continued follow-up as neurosurgery outpatients. A total of 59 patients who qualified for the inclusion criteria were included in the study. Results: Spine fixation was commonly performed at a single level mostly with sample size (54.2%, n=32) then at two levels (42.4%, n=25) and three levels (3.4%, n=2). Adjacent segment degeneration was present in the spine fixation level subgroup at a single level of 9 cases (28.12%), two levels of 9 cases (36%), and three-level fixations of 2 cases (100%). Six patients (10.2%) out of 59 patients developed radiculopathy. Among twenty-two cases (37.3%) with new changes at adjacent levels, reduced disc height was the most common one (18.6%, n=11). Anterior and posterior osteophytes with reduced disc height were found in 2 cases. Therefore, actual new changes were present in 20 cases only. The most common level of C4-C5 was observed for the development of ASD (13.6%, n=8). ASD developed at cranial to fusion in 13 cases (22%), caudal to fusion in 5 cases (8.5%), and at both levels in 2 patients. Conclusion: Adjacent segment disease was observed in a significant number of patients who underwent cervical spine surgery as evident from the results but only 6 out of 20 cases with radiological evidence of ASD were symptomatic. Changes were observed commonly at the C4/C5 level.

Sugammadex and blood loss during cervical spine fusion surgery.

Sugammadex (SUG) has been associated with changes in coagulation studies. Most reports have concluded a lack of clinical significance based on surgical blood loss with SUG use at the end of surgery. Previous reports have not measured its use intraoperatively during ongoing blood loss. Our hypothesis was that the use of SUG intraoperatively may increase bleeding. This was a single site retrospective study. Inclusion criteria were patients undergoing a primary posterior cervical spine fusion, aged over 18 years, between July 2015 and June 2021. The primary outcomes compared were intraoperative estimated blood loss (EBL) and postoperative drain output (PDO) between patients receiving SUG, neostigmine (NEO) and no NMB reversal agent. The objective was to determine if there was a difference in primary endpoints between patients administered SUG, NEO or no paralytic reversal agent. Primary endpoints were compared using analysis of variance with a P value of 0.05 used to determine statistical significance. Groups were compared using the Chi-squared test, rank sum or student's t test. A logistic regression model was constructed to account for differences between the groups. There was no difference in median EBL or PDO between groups. The use of SUG was not associated with an increase in odds for >500 milliliters (ml) of EBL. Increasing duration of surgery and chronic kidney disease were both associated with an increased risk for EBL >500 ml. Intraoperative use of SUG was not associated with increased bleeding. Any coagulation laboratory abnormalities previously noted did not appear to have an associated clinical significance.

Prolonged Opioid Use following Cervical Spine Fusion Surgeries-Incidence and Predictors of Use

Purpose: To determine the incidence and predictors of prolonged opioid use (OU) following cervical spine fusion surgery. Methods: This is a retrospective cohort study of all patients who underwent cervical arthrodesis for degenerative cervical spine disease over 7 years, between 2010 and 2016, who had at least one year of postoperative follow up at the University of Missouri hospitals. Review of medical records was done to collect data on patient's characteristics, associated pain measures (pre/postoperative VAS), ASA score, and pre/postoperative OU. The predictors of prolonged OU at 3, 6 and 12 months following surgery were identified using the logistic regression analyses. Significance was considered at p&lt;0.05. Results: Incidences of postoperative OU were 50%, 42.5% and 30.2% at 3, 6 and 12 months respectively. After adjustment for all possible confounders, preoperative OU was a significant predictor of postoperative OU at 3 months (OR=3.06, 95% CI: 1.28-7.34, p=0.012), 6 months (OR=2.86, 95% CI: 1.01-8.14, p=0.049) and 12 months (OR=7.22, 95% CI: 2.76-18.90, p&lt;0.001). Patients with cancer diagnosis were 23 times more likely to be prolonged opioid users for 12 months after surgery (OR= 23.13, 95% CI: 1.68-317.98, p=0.019). Conclusion: Perioperative opioid prescription for patients with cervical spine fusion is quite common. Further prospective study is necessary to minimize the effect of confounding variables such as; disease severity, and postoperative functional status on the associations between pre-and postoperative opioid use. Minimizing preoperative opioid use should be investigated as a way to mitigate long–term opioid use.

Utility of the Modified 5-Items Frailty Index to Predict Complications and Mortality After Elective Cervical, Thoracic and Lumbar Posterior Spine Fusion Surgery: Multicentric Analysis From ACS-NSQIP Database.

Retrospective review of multicentric data. The modified 5-item frailty index is a relatively new tool to assess the post-operative complication risks. It has been recently shown a good predictive value after posterior lumbar fusion. We aimed to compare the predictive value of the modified 5-item frailty index in cervical, thoracic and lumbar surgery. The American College of Surgeons - National Surgical Quality Improvement Program (ACS-NSQIP) Database 2015-2020 was used to identify patients who underwent elective posterior cervical, thoracic, or lumbar fusion surgeries for degenerative conditions. The mFI-5 score was calculated based on the presence of 5 co-morbidities: congestive heart failure within 30days prior to surgery, insulin-dependent or noninsulin-dependent diabetes mellitus, chronic obstructive pulmonary disease or pneumonia, partially dependent or totally dependent functional health status at time of surgery, and hypertension requiring medication. Multivariate analysis was used to assess the independent impact of increasing mFI-5 score on the postoperative morbidity while controlling for baseline clinical characteristics. 53252 patients were included with the mean age of 64.2 ± 7.2. 7946 suffered medical complications (14.9%), 1565 had surgical complications (2.9%), and 3385 were readmitted (6.3%), 363 died (.68%) within 30days postoperative (6.3%). The mFI-5 items score was significantly associated with higher rates of complications, readmission, and mortality in cervical, thoracic, and lumbar posterior fusion surgery. The modified 5-item frailty score is a reliable tool to predict complications, readmission, and mortality in patients planned for elective posterior spinal fusion surgery.

Pragmatic Prediction of Excessive Length of Stay After Cervical Spine Surgery With Machine Learning and Validation on a National Scale.

Extended postoperative hospital stays are associated with numerous clinical risks and increased economic cost. Accurate preoperative prediction of extended length of stay (LOS) can facilitate targeted interventions to mitigate clinical harm and resource utilization. To develop a machine learning algorithm aimed at predicting extended LOS after cervical spine surgery on a national level and elucidate drivers of prediction. Electronic medical records from a large, urban academic medical center were retrospectively examined to identify patients who underwent cervical spine fusion surgeries between 2008 and 2019 for machine learning algorithm development and in-sample validation. The National Inpatient Sample database was queried to identify cervical spine fusion surgeries between 2009 and 2017 for out-of-sample validation of algorithm performance. Gradient-boosted trees predicted LOS and efficacy was assessed using the area under the receiver operating characteristic curve (AUROC). Shapley values were calculated to characterize preoperative risk factors for extended LOS and explain algorithm predictions. Gradient-boosted trees accurately predicted extended LOS across cohorts, achieving an AUROC of 0.87 (SD = 0.01) on the single-center validation set and an AUROC of 0.84 (SD = 0.00) on the nationwide National Inpatient Sample data set. Anterior approach only, elective admission status, age, and total number of Elixhauser comorbidities were important predictors that affected the likelihood of prolonged LOS. Machine learning algorithms accurately predict extended LOS across single-center and national patient cohorts and characterize key preoperative drivers of increased LOS after cervical spine surgery.

Bone Graft Erosion into Hypopharynx Presenting with Stridor: Rare Late Complication Following Cervical Spine Surgery.

Cervical bone graft erosion occurs in about 2% of patients as a late complication following cervical spine fusion surgery. The usual presentation in such patients is dysphagia. Stridor is a very rare late complication of such bone erosions. We report a 66-year-old gentleman who presented with stridor, describe the management thereof.

Effects of focused continuous pulsed electromagnetic field therapy on early tendon-to-bone healing.

AimsRotator cuff (RC) tears are common musculoskeletal injuries which often require surgical intervention. Noninvasive pulsed electromagnetic field (PEMF) devices have been approved for treatment of long-bone fracture nonunions and as an adjunct to lumbar and cervical spine fusion surgery. This study aimed to assess the effect of continuous PEMF on postoperative RC healing in a rat RC repair model.MethodsA total of 30 Wistar rats underwent acute bilateral supraspinatus tear and repair. A miniaturized electromagnetic device (MED) was implanted at the right shoulder and generated focused PEMF therapy. The animals’ left shoulders served as controls. Biomechanical, histological, and bone properties were assessed at three and six weeks.ResultsExtension of the tendon from preload to the maximum load to failure was significantly better in the PEMF-treated shoulders at three weeks compared to controls (p = 0.038). The percentage strain was significantly higher in the PEMF group at both timepoints (p = 0.037). Collagen organization was significantly better (p = 0.034) as was tissue mineral density in the PEMF-treated group at three weeks (p = 0.028). Tendon immunohistochemistry revealed a prominent increase in type I collagen at the repair site at three weeks following continuous PEMF treatment compared with controls. None of the other tested parameters differed between the groups.ConclusionMED-generated PEMF may enhance early postoperative tendon-to-bone healing in an acute rat supraspinatus detachment and repair model. Superior biomechanical elasticity parameters together with better collagen organization suggest improved RC healing.Cite this article: Bone Joint Res 2021;10(5):298–306.

Recurrent cerebellar infarction due to vertebral artery dissection in an athetotic patient

AbstractA 42‐year‐old man with longstanding athetotic‐type cerebral palsy and history of cervical spine fusion surgery was affected by multiple episodes of vertebral artery dissections, resulting in bilateral cerebellar infarction. Continuous involuntary movements noted in the upper limbs and neck, as well as a limited cervical range of motion due to the operation might have precipitated the dissecting events.

Prevalence of Poor Bone Quality in Patients Undergoing Spine Surgery: A Comprehensive Approach.

Study Design:A cross-sectional study.Objectives:To investigate the prevalence of poor bone quality in patients requiring spine surgery through comprehensive evaluation with bone mass density (BMD), trabecular bone score (TBS), FRAX, and vitamin D status.Methods:we prospectively recruited patients of > 50 years old candidates for lumbar or cervical spine fusion surgery at our institution. Recorded data were: demographic, body mass index (BMI), risk factors for osteoporosis, daily calcium intake, FRAX score, disability index for lumbar and cervical spine, and VAS for pain. Serum 25 OH vitamin D, BMD using DXA, and TBS was also evaluated.Results:A total of 104 patients were recruited, osteoporosis by BMD was detected in 9.6%, and osteopenia in 34.6% of patients. 69.4% of patients with osteopenia had a degraded or partially degraded bone microarchitecture by TBS.Low levels of vitamin D were detected in 79.8% of patients. Increased pain was associated with low BMD levels. Adding TBS to BMD for the determination of bone strength resulted in 33.7% of patients with poor bone quality. Lastly, the combination of BMD, TBS, and FRAX revealed 37,5% of patients with poor bone quality.Conclusions:Poor bone quality and low vitamin D levels are quite common among patients aged ≥ 50 years undergoing spine surgery. DXA alone seems not enough for preoperative identification of impaired bone quality cases. FRAX is useful for identifying high-risk patients and TBS is a valuable complement to DXA by adding the dimension of bone quality.

3D-printed navigation template in cervical spine fusion: a systematic review and meta-analysis.

To explore the effectiveness and advantage of three-dimensional (3D)-printed navigation templates (3DPN-template) assisted in cervical spine fusion (CSF) surgery as compared to conventional surgery. An electronic literature search in PubMed, Scopus, Web of Science, and Cochrane was conducted for studies of 3DPN-templates in CSF up to May 2020. Outcome measures as the accuracy rate, operation time, intra-operative blood loss, and fluoroscopy used, associated with CSF were extracted. Mean difference based on changes was quantified using Hedges' g. From 4414 potentially relevant studies, 61 full-text publications were screened. Thirteen studies comprising 330 cases with 1323 screw placements were eligible for inclusion. For template group, pooled estimates were as follows: 97.3% accuracy rate for screw placement, 144.7min for operating time, 273.6ml for blood loss, and 3.2min for fluoroscopic times. A significantly positive difference was observed between the template group compared to control group in terms of accuracy rate of screw placement (Z = 5.3), operation time (Z = 2.41), intra-operative blood loss (Z = 2.64), and fluoroscopic times (Z = 3.64) (all, P value < 0.0001). Risk of bias for studies under review was assessed using the Newcastle-Ottawa Scale (NOS), and 11 studies were found as having high quality. Overall, funnel plot and Begg's test did not indicate obvious publication bias. The 3D-printed navigation template in the cervical surgery can improve accuracy of pedicle screw placement and consequently improve outcomes. In future, multi-center efforts are needed to validate the relationships found in this review.

The C2 Cortical Screw, an Alternative Fixation Technique for the C2 Segment During High Cervical Spine Surgery: Technical Note

For posterior fixation of C2 vertebra (the axis), several fixation techniques such as pedicle screw, laminar screw, and pars screw have been reported. A pedicle screw (PS) is considered the strongest among the techniques, but certain situations make PS fixation impossible or difficult. These include patients with a narrow C2 pedicle or high-riding vertebral artery. We introduced an alternative screw technique for C2 that addressed the aforementioned problems with safely placing it, which we termed a cortical screw (CS) for C2. Among a total of 28 cases using C2 CS for high cervical spine surgery, 2 cases using C2 CS were described. One patient was a 76-year old woman with a gait disturbance and myelopathic symptoms and diagnosed with C1-C2 myelopathy and translational instability. The other case was 54-year old man with posterior neck pain after traffic accident and diagnosed with C1-C2 fracture-dislocation. We used the C2 CS as an alternative technique for high cervical spine surgery in these patients and describe the ideal entry point and trajectory. A postoperative computed tomography scan confirmed proper positioning of the C1 posterior arch screw and C2 CS, with satisfactory reduction of the C2 dens and adequate restoration of the C1-C2 spinal canal. The patient experienced no screw-related postoperative complications, and postoperative 1-year computed tomography images showed that solid union and good alignment of C1-2 segment was achieved. C2 CS can be suitable alternative for C2 screw fixation technique in posterior high cervical spine fusion surgery.

Development of a VR Simulator for Training of Posterior Cervical Spine Fusion Surgery

AbstractIt is important to avoid iatrogenic injuries of nerves and blood vessels during the pedicle screw insertion stage of posterior cervical spine decompression and fusion surgery. First, it is necessary to determine the length and angulation of the pedicle screws for safety and stability. Second, it is necessary to drill precise preparation holes for the pedicle screws using a pedicle probe. In this work, we developed a VR training system for pedicle screw planning and basic drilling skills. The VR system was built with a pen‐style haptic device and a head‐mounted display. Trainees used the haptic pen as a virtual pedicle probe. In order to simulate bone hardness and stress accumulation at the virtual pedicle probe tip in the virtual surgery, we developed a voxel‐based bone drilling simulator. To reduce the heavy load required for voxel processing, the simulator was constructed as a hybrid system that included a removal volume voxel model for drilling areas and a fixed polygonal mesh model for other areas. 3D models of a cervical spine were generated from CT scan images of a patient. This paper evaluated the system through a subjective evaluation by a specialist and via the training results for novice trainees. We discuss the evaluation results and training effectiveness with the simulator. © 2020 Institute of Electrical Engineers of Japan. Published by Wiley Periodicals LLC.

Recent trends in medicare utilization and reimbursement for anterior cervical discectomy and fusion

Anterior cervical discectomy and fusion (ACDF) has been considered the gold standard for treating various cervical spine pathologies stemming from cervical degenerative disorders. While cervical artificial disc replacement has emerged as an alternative in select cases, ACDF still remains a commonly performed procedure. This study seeks to define the costs of ACDF and identify trends and variations in ACDF volume, utilization, and surgeon and hospital reimbursement rates. Retrospective analysis of patients undergoing ACDF PATIENT SAMPLE: Medicare patients undergoing ACDF between 2012 and 2017 OUTCOME MEASURES: ACDF volume, utilization rates, and surgeon/hospital reimbursement rates METHODS: This study tracked annual Medicare claims and payments to ACDF surgeons using publicly-available databases and aggregated data at the county level. Descriptive statistics and multivariate regression models were used to evaluate trends in procedure volume, utilization rates (per 10,000 Medicare beneficiaries), and reimbursement rates, and to examine associations between county-specific variables (ie, urban or rural, average household income, poverty rate, percent Medicare population, race/ethnicity demographics), and ACDF utilization and reimbursement rates. A total of 264,673 ACDF surgeries were performed in the Medicare population from 2012 to 2017, with a 24.2% increase in annual procedure volume. Utilization also increased by 6.5% from 8.0 surgeries per 10,000 Medicare beneficiaries in 2012 to 8.5 in 2017. Hospital reimbursements for cervical spine fusion surgeries without complications or co-morbidities experienced nominal and inflation-adjusted increases of 9.5% and 0.7%, respectively, from $12,030.11 in 2012 to $13,167.64 in 2017. Surgeon reimbursements for single-level and multilevel ACDF each nominally decreased from $958.11 and $1,173.01, respectively, in 2012 to $950.34 and $1,138.41 in 2017 (a 0.8% and 2.9% decrease, respectively), but after adjusting for inflation, reimbursements per case fell by an average of 8.7% and 10.7%, respectively. In contrast, mean reimbursements per case for hospitals rose by 7.1% (1.5% inflation-adjusted decrease). A significant upward yearly trend in ambulatory surgical centers volume, resulted in a net increase of 184.5% between 2015 and 2017 (p<.001). While ACDF volume and utilization has continued to increase since 2012, Medicare payments to hospitals and surgeons have struggled to keep up with inflation. Our study confirms that Medicare reimbursement per case continues to decrease at a disproportionate rate for surgeons, compared to hospitals. The increasing trend in procedures performed at ambulatory surgical centers shows promise for a future model of cost-efficient and value-based care.

Rates and risk factors associated with 90-day readmission following cervical spine fusion surgery: analysis of the Michigan Spine Surgery Improvement Collaborative (MSSIC) registry

BACKGROUND CONTEXTHospital readmission rates are an increasingly important focus. Identifying patients at risk for readmission can help decrease those rates and thus decrease the overall cost of care. PURPOSEWe sought to report the rates and the risk factors associated with 90-day hospital readmission after degenerative cervical spine surgery via either an anterior or posterior approach. STUDY DESIGNRetrospective review of prospectively collected database PATIENT SAMPLEMichigan Spine Surgery Improvement Collaborative (MSSIC) registry OUTCOME MEASURESHospital readmission at 90 days METHODSThe MSSIC registry prospectively enrolls patients undergoing surgery for degenerative cervical spine disease. The registry was queried over a 4-year period to determine patient characteristics and risk factors associated with unplanned readmission at 90 days following degenerative cervical spine fusion surgery through either an anterior or posterior approach. Univariate and multivariate regression modeling was used to compare patient characteristics and odds of readmission. RESULTSOf 3,762 patients who underwent an anterior approach, 202 (5.4%) were readmitted within 90 days. Of 693 patients who underwent a posterior approach, 85 (12.3%) were readmitted within 90 days. Risk factors associated with increased likelihood of readmission after the anterior approach were male sex (odds ratio [OR] 1.56, confidence interval [CI] 1.10–2.20), American Society of Anesthesiologists class >2 (OR 1.70, CI 1.26–2.30), and increased length of stay (OR 1.10, CI 1.03–1.19). Factors associated with decreased likelihood of readmission after the anterior approach were being independently ambulatory preoperatively (OR 0.59, CI 0.46–0.76) and holding private insurance (OR 0.67, CI 0.50–0.90). A history of previous spine surgery was associated with increased risk of readmission after the posterior approach (OR 1.76, CI 1.37–2.25). Pain was the most common single reason cited for readmission after either approach (9% anterior, 13% posterior). After an anterior approach, common surgical reasons for readmission include new radicular findings (8%), dysphagia (6%), and surgical site hematoma (5%), whereas common medical reasons include pneumonia (7%), infection outside the surgical site (6%), and an electrolyte issue. After a posterior approach, common surgical reasons for readmission after 90 days include surgical site infection (8%) and new radicular findings (6%), whereas common medical reasons include infection outside the surgical site (9%), urinary tract infection (8%), and an abdominal issue (8%). CONCLUSIONSAnalysis of a large multicentered, spine-specific database for elective cervical spine fusion surgery demonstrated an unplanned 90-day readmission rate of 5.4% for the anterior approach and 12.3% for the posterior approach. Factors associated with readmission for the anterior approach include male sex, American Society of Anesthesiologists class >2, increased length of stay, holding private insurance, and being ambulatory preoperatively. A history of previous spine surgery was associated with increased odds of readmission after the posterior approach.

Crossing the Cervicothoracic Junction in Cervical Arthrodesis Results in Lower Rates of Adjacent Segment Disease Without Affecting Operative Risks or Patient-Reported Outcomes.

Retrospective cohort study. To evaluate the risks and benefits of crossing the cervicothoracic junction (CTJ) in cervical arthrodesis. Whether the CTJ should be crossed in cervical arthrodesis remains up for debate. Keeping C7 as the distal end of the fusion risks adjacent segment disease (ASD) and can result in myelopathy or radiculopathy. Longer fusions are thought to increase operative risk and complexity but result in lower rates of ASD. Patients undergoing cervical spine fusion surgery ending at C7 or T1 with ≥1-year follow-up were included. To evaluate operative risk, estimated blood loss (EBL), operative time, and length of hospital stay were collected. To evaluate patient-reported outcomes (PROs), Neck Disability Index (NDI) and SF-12 questionnaires (PCS12 and MCS12) were obtained at follow-up. Revision surgery data were also obtained. A total of 168 patients were included and divided into a C7 end-of-fusion cohort (NC7=59) and a T1 end-of-fusion cohort (NT1=109). Multivariate regression analysis adjusting for age, sex, race, surgical approach, and number of levels fused showed that EBL (P=0.12), operative time (P=0.07), and length of hospital stay (P=0.06) are not significantly different in the C7 and T1 end-of-fusion cohorts. Multivariate regression of PROs showed no significant difference in NDI (P=0.70), PCS12 (P=0.23), or MCS12 (P=0.15) between cohorts. Fisher analysis showed significantly higher revision rates in the C7 end-of-fusion cohort (7/59 for C7 vs. 2/109 for T1; odds ratio, 6.4; 95% confidence interval, 1.2-65.1; P=0.01). Crossing the CTJ in cervical arthrodesis does not increase operative risk as measured by blood loss, operative time, and length of hospital stay. However, it leads to lower revision rates, likely because of the avoidance of ASD, and comparable PROs. Thus, crossing the CTJ may help prevent ASD without negatively affecting operative risk or long-term PROs.