Sivaganesan, Ahilan

Objective Preclinical studies suggest that robotic carotid artery stenting (CAS) could be superior to manual CAS. However, very limited comparative data exists comparing robotic and manual CAS patients. In addition, no data exists comparing the costs of manual and robotic CAS. Methods All robotic CAS cases at 2 academic neurosurgery centers were retrospectively reviewed and 1:1 propensity matched with manual CAS cases. Personnel costs, supply costs, and total procedure costs were collected in collaboration with hospital administration using time‐driven activity‐based cost‐analysis (TDABC). Results 24 robotic CAS cases were performed between 2019 and 2023. Co‐morbidities and baseline procedural characteristics were well‐matched between robotic and manual cases. Unplanned manual conversion was observed in only one robotic case (4.2%). Robotic CAS complications and outcomes were comparable to manual. Robotic CAS was associated with a significantly increased fluoroscopy time (29.0 vs. 19.2 min.; p<0.001). Robotic procedure time (88.9±18.2 min.) was significantly (p=0.003) higher than manual (68.72±22.4 min.). Health professional costs ($1,589.71±176.92, $1,375.99±233.39, p<0.005), supply cost ($3,918.25±421.20, $2,152.74±1,030.26, p<0.001) and total procedure costs ($5,306.11±608.95, $3,437.56±1,165.67, p<0.001) were greater for robotic CAS. Conclusions With a low rate of technical failure and post‐operative complications, we show robotic carotid artery stenting is safe and feasible in the first multi‐center and largest sample to date. In addition, robotic CAS achieves comparable clinical outcomes. Robotic CAS was associated with increased fluoroscopy time, but fluoroscopy time decreased as operators gained familiarity with the CorPath GRX. Robotic CAS was associated with a greater procedural cost, which was driven by greater personnel and supply costs. Our findings highlight the need for further studies to optimize robotic CAS and reduce its associated costs.

OBJECTIVE Preclinical studies suggest that robotic carotid artery stenting (CAS) could be superior to manual CAS. However, very limited comparative data exist for patients who have undergone robotic versus manual CAS. In addition, no data exist comparing the costs of manual and robotic CAS. METHODS All robotic CAS cases at two academic neurosurgery centers were retrospectively reviewed and 1:1 propensity matched with manual CAS cases. Personnel costs, supply costs, and total procedure costs were collected in collaboration with hospital administration by using time-driven activity-based cost analysis. RESULTS A total of 24 robotic CAS operations were performed between 2019 and 2023. Comorbidities and baseline procedural characteristics were well matched between robotic and manual cases. Unplanned manual conversion was observed in only 1 robotic case (4.2%). Robotic CAS complications and outcomes were comparable to manual. Robotic CAS was associated with a significantly increased fluoroscopy time (29.0 vs 19.2 minutes; p < 0.001). Robotic procedure time (88.9 ± 18.2 minutes) was significantly (p = 0.003) longer than manual time (68.72 ± 22.4 minutes). Health personnel costs ($1589.71 ± $176.92 vs $1375.99 ± $233.39, p = 0.005); supply costs ($3918.25 ± $421.20 vs $2152.74 ± $1030.26, p < 0.001); and total procedure costs ($5306.11 ± $608.95 vs $3437.56 ± $1165.67, p < 0.001) were greater for robotic CAS. CONCLUSIONS In the first multicenter study and largest sample to date, the authors show that robotic CAS, with a low rate of procedural failure and postoperative complications, is safe and feasible. In addition, robotic CAS achieves comparable clinical outcomes to manual CAS. Robotic CAS was associated with increased fluoroscopy time, but fluoroscopy time decreased as operators gained familiarity with the CorPath GRX system. Robotic CAS was associated with a greater procedural cost, which was driven by greater personnel and supply costs. Robotic CAS failed to show superiority to manual CAS. These findings set a foundation for randomized controlled trials of robotic CAS, and also highlight the need for further studies to optimize robotic CAS and reduce its associated costs.

Study Design. Retrospective analysis of prospectively collected registry data. Objective. To develop and validate prediction models for 12-month patient-reported outcomes of disability, pain, and myelopathy in patients undergoing elective cervical spine surgery. Summary of Background Data. Predictive models have the potential to be utilized preoperatively to set expectations, adjust modifiable characteristics, and provide a patient-centered model of care. Methods. This study was conducted using data from the cervical module of the Quality Outcomes Database. The outcomes of interest were disability (Neck Disability Index:), pain (Numeric Rating Scale), and modified Japanese Orthopaedic Association score for myelopathy. Multivariable proportional odds ordinal regression models were developed for patients with cervical radiculopathy and myelopathy. Patient demographic, clinical, and surgical covariates as well as baseline patient-reported outcomes scores were included in all models. The models were internally validated using bootstrap resampling to estimate the likely performance on a new sample of patients. Results. Four thousand nine hundred eighty-eight patients underwent surgery for radiculopathy and 2641 patients for myelopathy. The most important predictor of poor postoperative outcomes at 12-months was the baseline Neck Disability Index score for patients with radiculopathy and modified Japanese Orthopaedic Association score for patients with myelopathy. In addition, symptom duration, workers’ compensation, age, employment, and ambulatory and smoking status had a statistically significant impact on all outcomes (P < 0.001). Clinical and surgical variables contributed very little to predictive models, with posterior approach being associated with higher odds of having worse 12-month outcome scores in both the radiculopathy and myelopathy cohorts (P < 0.001). The full models overall discriminative performance ranged from 0.654 to 0.725. Conclusions. These predictive models provide individualized risk-adjusted estimates of 12-month disability, pain, and myelopathy outcomes for patients undergoing spine surgery for degenerative cervical disease. Predictive models have the potential to be used as a shared decision-making tool for evidence-based preoperative counselling. Level of Evidence: 2.

OBJECTIVE Patient satisfaction with treatment outcome is gaining an increasingly important role in assessing the value of surgical spine care delivery. Nationwide data evaluating the predictors of patient satisfaction in elective cervical spine surgery are lacking. The authors sought to decipher the impacts of the patient, surgical practice, and surgeon on satisfaction with outcome following anterior cervical discectomy and fusion (ACDF). METHODS The authors queried the Quality Outcomes Database for patients undergoing 1- to 2-level ACDF for degenerative spine disease since 2013. Patient satisfaction with the surgical outcome as measured by the North American Spine Society (NASS) scale comprised the primary outcome. A multivariable proportional odds logistic regression model was constructed with adjustments for baseline patient characteristics and surgical practice and surgeon characteristics as fixed effects. RESULTS A total of 4148 patients (median age 54 years, 48% males) with complete 12-month NASS satisfaction data were analyzed. Sixty-seven percent of patients answered that “surgery met their expectations” (n = 2803), while 20% reported that they “did not improve as much as they had hoped but they would undergo the same operation for the same results” (n = 836). After adjusting for a multitude of patient-specific as well as hospital- and surgeon-related factors, the authors found baseline Neck Disability Index (NDI) score, US geographic region of hospital, patient race, insurance status, symptom duration, and Workers’ compensation status to be the most important predictors of patient satisfaction. The discriminative ability of the model was satisfactory (c-index 0.66, overfitting-corrected estimate 0.64). CONCLUSIONS The authors’ results found baseline NDI score, patient race, insurance status, symptom duration, and Workers’ compensation status as well as the geographic region of the hospital to be the most important predictors of long-term patient satisfaction after a 1- to 2-level ACDF. The findings of the present analysis further reinforce the role of preoperative discussion with patients on setting treatment goals and realistic expectations.

Abstract BACKGROUND Degenerative cervical myelopathy (DCM) is a progressive disease resulting from cervical cord compression. The modified Japanese Orthopaedic Association (mJOA) is commonly used to grade myelopathic symptoms, but its persistent postoperative improvement has not been previously explored. OBJECTIVE To utilize the Quality Outcomes Database (QOD) to evaluate the trajectory of outcomes in those operatively treated for DCM. METHODS This study is a retrospective analysis of prospectively collected data. The QOD was queried for patients undergoing elective surgery for DCM. Patients were divided into mild (≥14), moderate (9-13), or severe (<9) categories for their baseline severity of myelopathic symptoms (mJOA scores). A parsimonious multivariable logistic regression model was fitted with 2 points improvement on mJOA from 3- to 12-mo follow-up as the outcome of interest. RESULTS A total of 2156 patients who underwent elective surgery for DCM and had complete 3- and 12-mo follow-up were included in our analysis. Patients improved significantly from baseline to 3-mo on their mJOA scores, regardless of their baseline mJOA severity. After adjusting for the relevant preoperative characteristics, the baseline mJOA categories had significant impact on outcome of whether a patient keeps improving in mJOA score from 3 to 12 mo postsurgery. Patient with severe mJOA score at baseline had a higher likelihood of improvement in their myelopathic symptoms, compared to patients with mild mJOA score in. CONCLUSION Most patients achieve improvement on a shorter follow-up; however, patients with severe symptoms keep on improving until after a longer follow-up. Preoperative identification of such patients helps the clinician settling realistic expectations for each follow-up timepoint.

Abstract BACKGROUND Modern healthcare reforms focus on identifying and measuring the quality and value of care. Patient satisfaction is particularly important in the management of degenerative cervical radiculopathy (DCR) since it leads to significant neck pain and disability primarily affecting the patients’ quality of life. OBJECTIVE To determine the association of baseline and 12-mo Neck Disability Index (NDI) with patient satisfaction after elective surgery for DCR. METHODS The Quality Outcomes Database cervical module was queried for patients who underwent elective surgery for DCR. A multivariable proportional odds regression model was fitted with 12-mo satisfaction as the outcome. The covariates for this model included patients’ demographics, surgical characteristics, and baseline and 12-mo patient reported outcomes (PROs). Wald-statistics were calculated to determine the relative importance of each independent variable for 12-mo patient satisfaction. RESULTS The analysis included 2206 patients who underwent elective surgery for DCR. In multivariable analysis, after adjusting for baseline and surgery specific variables, the 12-mo NDI score showed the highest association with 12-mo satisfaction (Waldχ2-df = 99.17, 58.1% of total χ2). The level of satisfaction increases with decrease in 12-mo NDI score regardless of the baseline NDI score. CONCLUSION Our study identifies 12-mo NDI score as a very influential driver of 12-mo patient satisfaction after surgery for DCR. In addition, there are lesser contributions from other 12-mo PROs, baseline Numeric Rating Scale for arm pain and American Society of Anesthesiologists (ASA) grade. The baseline level of disability was found to be irrelevant to patients. They seemed to only value their current level of disability, compared to baseline, in rating satisfaction with surgical outcome.

Study Design. This study retrospectively analyzes prospectively collected data. Objective. Here in this study we aim to determine the factors which impact a patient's ability to return to work (RTW) in the setting of cervical spine surgery in patients without worker's compensation status. Summary of Background Data. Surgical management of degenerative cervical disease has proven cost-effectiveness and shown significant improvement in quality of life. However, the ability to RTW is an important clinical outcome for preoperatively employed patients. Methods. All adult patients undergoing elective surgery for cervical degenerative disease at our institution are enrolled in a prospective, web-based registry. A multivariable Cox proportional hazards regression model was built for time to RTW. The variables included in the model were age, sex, smoking status, occupation type, number of levels operated on, ASA grade, body mass index, history of diabetes, history of coronary artery disease (CAD), history of chronic obstructive pulmonary disease (COPD), anxiety, depression, myelopathy at presentation, duration of symptoms more than 12 months, diagnosis, type of surgery performed, and preoperative Neck Disability Index, EuroQol Five Dimensions, and Numeric Rating Scale pain scores for neck pain and arm pain scores. Results. Of the total 324 patients with complete 3-month follow-up data 83% (n = 269) returned to work following surgery. The median time to RTW was 35 days (range, 2–90 d). Patients with a labor-intensive occupation, higher ASA grade, history of CAD, and history of COPD were less likely to RTW. The likelihood of RTW was lower in patients with a diagnosis of disc herniation compared with cervical stenosis, patients undergoing cervical corpectomy compared laminectomy and fusion and patient with longer operative time. Conclusion. Our study identifies the various factors associated with a lower likelihood of RTW at 3 months after cervical spine surgery in the non-worker's compensation setting. This information provides expectations for the patient and employer when undergoing cervical spine surgery. Level of Evidence: 3

Study Design. This study retrospectively analyzes prospectively collected data. Objective. Here, we aim to determine the influence of preoperative and 12-month modified Japanese Orthopedic Association (mJOA) on satisfaction and understand the change in mJOA severity classification after surgical management of degenerative cervical myelopathy (DCM). Summary of Background Data. DCM is a progressive degenerative spine disease resulting from cervical cord compression. The natural progression of DCM is variable; some patients experience periods of stability, while others rapidly deteriorate following disease onset. The mJOA is commonly used to grade and categorize myelopathy symptoms, but its association with postoperative satisfaction has not been previously explored. Methods. The quality and outcomes database (QOD) was queried for patients undergoing elective surgery for DCM. Patients were divided into mild (≥14), moderate (9 to 13), or severe (<9) categories on the mJOA scores. A McNemar–Bowker test was used to assess whether a significant proportion of patients changed mJOA category between preoperative and 12 months postoperative. A multivariable proportional odds ordinal logistic regression model was fitted with 12-month satisfaction as the outcome of interest. Results. We identified 1963 patients who underwent elective surgery for DCM and completed 12-months follow-ups. Comparing mJOA severity level preoperatively and at 12 months revealed that 55% remained in the same category, 37% improved, and 7% moved to a worse category. After adjusting for baseline and surgery-specific variables, the 12-month mJOA category had the highest impact on patient satisfaction (P < 0.001). Conclusion. Patient satisfaction is an indispensable tool for measuring quality of care after spine surgery. In this sample, 12-month mJOA category, regardless of preop mJOA, was significantly correlated with satisfaction. Given these findings, it is important to advise patients of the probability that surgery will change their mJOA severity classification and the changes required to achieve postoperative satisfaction. Level of Evidence: 3

OBJECTIVE Back pain and neck pain are two of the most common causes of work loss due to disability, which poses an economic burden on society. Due to recent changes in healthcare policies, patient-centered outcomes including return to work have been increasingly prioritized by physicians and hospitals to optimize healthcare delivery. In this study, the authors used a national spine registry to identify clinical factors associated with return to work at 3 months among patients undergoing a cervical spine surgery. METHODS The authors queried the Quality Outcomes Database registry for information collected from April 2013 through March 2017 for preoperatively employed patients undergoing cervical spine surgery for degenerative spine disease. Covariates included demographic, clinical, and operative variables, and baseline patient-reported outcomes. Multiple imputations were used for missing values and multivariable logistic regression analysis was used to identify factors associated with higher odds of returning to work. Bootstrap resampling (200 iterations) was used to assess the validity of the model. A nomogram was constructed using the results of the multivariable model. RESULTS A total of 4689 patients were analyzed, of whom 82.2% (n = 3854) returned to work at 3 months postoperatively. Among previously employed and working patients, 89.3% (n = 3443) returned to work compared to 52.3% (n = 411) among those who were employed but not working (e.g., were on a leave) at the time of surgery (p < 0.001). On multivariable logistic regression the authors found that patients who were less likely to return to work were older (age > 56–65 years: OR 0.69, 95% CI 0.57–0.85, p < 0.001; age > 65 years: OR 0.65, 95% CI 0.43–0.97, p = 0.02); were employed but not working (OR 0.24, 95% CI 0.20–0.29, p < 0.001); were employed part time (OR 0.56, 95% CI 0.42–0.76, p < 0.001); had a heavy-intensity (OR 0.42, 95% CI 0.32–0.54, p < 0.001) or medium-intensity (OR 0.59, 95% CI 0.46–0.76, p < 0.001) occupation compared to a sedentary occupation type; had workers’ compensation (OR 0.38, 95% CI 0.28–0.53, p < 0.001); had a higher Neck Disability Index score at baseline (OR 0.60, 95% CI 0.51–0.70, p = 0.017); were more likely to present with myelopathy (OR 0.52, 95% CI 0.42–0.63, p < 0.001); and had more levels fused (3–5 levels: OR 0.46, 95% CI 0.35–0.61, p < 0.001). Using the multivariable analysis, the authors then constructed a nomogram to predict return to work, which was found to have an area under the curve of 0.812 and good validity. CONCLUSIONS Return to work is a crucial outcome that is being increasingly prioritized for employed patients undergoing spine surgery. The results from this study could help surgeons identify at-risk patients so that preoperative expectations could be discussed more comprehensively.

Study Design. This study retrospectively analyzes prospectively collected data. Objective. The primary aim of this study is to present a scheme for patient-reported outcome (PRO)-based, risk-adjusted rankings of spine surgeons and sites that perform elective lumbar surgery, using the Quality and Outcomes Database (QOD). Summary of Background Data. There is currently no means of determining which spine surgeons or centers are positive or negative outliers with respect to PROs for elective lumbar surgery. This is a critical gap as we move toward a value-based model of health care in which providers assume more accountability for the effectiveness of their treatments. Methods. Random effects regression models were fit for the following outcomes, with QOD site as a fixed effect but surgeon ID as a random effect: Oswestry Disability Index, EQ-5D, back pain and leg pain, and satisfaction. Hierarchical Bayesian models were also fit for each outcome, with QOD site as a random effect and surgeon as a nested random effect. Results. Our study cohort consists of 8834 patients who underwent surgery by 124 QOD surgeons, for the degenerative lumbar diseases. Nonoverlapping Bayesian credible intervals demonstrate that the variance attributed to QOD site was greater than the nested variance attributed to surgeon ID for the included PROs. Conclusion. This study presents a novel strategy for the risk-adjusted, PRO-based ranking of spine surgeons and practices. This can help identify positive and negative outliers, thereby forming the basis for large-scale quality improvement. Assuming adequate coverage of baseline risk adjustment, the choice of surgeon matters when considering PROs after lumbar surgery; however, the choice of site appears to matter more. Level of Evidence: 3