The impact of anxiety and depression on lumbar spine surgical outcomes: a Michigan Spine Surgery Improvement Collaborative study.

OBJECTIVE: The presence of depression and anxiety has been associated with negative outcomes in spine surgery patients. While it seems evident that a history of depression or anxiety can negatively influence outcome, the exact additive effect of both has not been extensively studied in a multicenter trial. The purpose of this study was to investigate the relationship between a patient's history of anxiety and depression and their patient-reported outcomes (PROs) after lumbar surgery. METHODS: Patients in the Michigan Spine Surgery Improvement Collaborative registry undergoing lumbar spine surgery between July 2016 and December 2021 were grouped into four cohorts: those with a history of anxiety only, those with a history of depression only, those with both, and those with neither. Primary outcomes were achieving the minimal clinically important difference (MCID) for the Patient-Reported Outcomes Measurement Information System Physical Function 4-item Short Form (PROMIS PF), EQ-5D, and numeric rating scale (NRS) back pain and leg pain, and North American Spine Society patient satisfaction. Secondary outcomes included surgical site infection, hospital readmission, and return to the operating room. Multivariate Poisson generalized estimating equation models were used to report incidence rate ratios (IRRs) from patient baseline variables. RESULTS: Of the 45,565 patients identified, 3941 reported a history of anxiety, 5017 reported a history of depression, 9570 reported both, and 27,037 reported neither. Compared with those who reported having neither, patients with both anxiety and depression had lower patient satisfaction at 90 days (p = 0.002) and 1 year (p = 0.021); PROMIS PF MCID at 90 days (p < 0.001), 1 year (p < 0.001), and 2 years (p = 0.006); EQ-5D MCID at 90 days (p < 0.001), 1 year (p < 0.001), and 2 years (p < 0.001); NRS back pain MCID at 90 days (p < 0.001) and 1 year (p < 0.001); and NRS leg pain MCID at 90 days (p < 0.001), 1 year (p = 0.024), and 2 years (p = 0.027). Patients with anxiety only (p < 0.001), depression only (p < 0.001), or both (p < 0.001) were more likely to be readmitted within 90 days. Additionally, patients with anxiety only (p = 0.015) and both anxiety and depression (p = 0.015) had higher rates of surgical site infection. Patients with anxiety only (p = 0.006) and depression only (p = 0.021) also had higher rates of return to the operating room. CONCLUSIONS: The authors observed an association between a history of anxiety and depression and negative outcome after lumbar spine surgery. In addition, they found an additive effect of a history of both anxiety and depression with an increased risk of negative outcome when compared with either anxiety or depression alone.

Risk factors of emergency department visits following elective cervical and lumbar surgical procedures: a multi-institution analysis from the Michigan Spine Surgery Improvement Collaborative.

OBJECTIVE: Emergency department visits 90 days after elective spinal surgery are relatively common, with rates ranging from 9% to 29%. Emergency visits are very costly, so their reduction is of importance. This study's objective was to evaluate the reasons for emergency department visits and determine potentially modifiable risk factors. METHODS: This study retrospectively reviewed data queried from the Michigan Spine Surgery Improvement Collaborative (MSSIC) registry from July 2020 to November 2021. MSSIC is a multicenter (28-hospital) registry of patients undergoing cervical and lumbar degenerative spinal surgery. Adult patients treated for elective cervical and/or lumbar spine surgery for degenerative pathology (spondylosis, intervertebral disc disease, low-grade spondylolisthesis) were included. Emergency department visits within 90 days of surgery (outcome measure) were analyzed utilizing univariate and multivariate regression analyses. RESULTS: Of 16,224 patients, 2024 (12.5%) presented to the emergency department during the study period, most commonly for pain related to spinal surgery (31.5%), abdominal problems (15.8%), and pain unrelated to the spinal surgery (12.8%). On multivariate analysis, age (per 5-year increase) (relative risk [RR] 0.94, 95% CI 0.92-0.95), college education (RR 0.82, 95% CI 0.69-0.96), private insurance (RR 0.79, 95% CI 0.70-0.89), and preoperative ambulation status (RR 0.88, 95% CI 0.79-0.97) were associated with decreased emergency visits. Conversely, Black race (RR 1.30, 95% CI 1.13-1.51), current diabetes (RR 1.13, 95% CI 1.01-1.26), history of deep venous thromboembolism (RR 1.28, 95% CI 1.16-1.43), history of depression (RR 1.13, 95% CI 1.03-1.25), history of anxiety (RR 1.32, 95% CI 1.19-1.46), history of osteoporosis (RR 1.21, 95% CI 1.09-1.34), history of chronic obstructive pulmonary disease (RR 1.19, 95% CI 1.06-1.34), American Society of Anesthesiologists class > II (RR 1.18, 95% CI 1.08-1.29), and length of stay > 3 days (RR 1.29, 95% CI 1.16-1.44) were associated with increased emergency visits. CONCLUSIONS: The most common reasons for emergency department visits were surgical pain, abdominal dysfunction, and pain unrelated to index spinal surgery. Increased focus on postoperative pain management and bowel regimen can potentially reduce emergency visits. The risks of diabetes, history of osteoporosis, depression, and anxiety are areas for additional preoperative screening.

Does Tighter Glycemic Control Beyond Hemoglobin A1c of 8% Improve Outcome for Lumbar Spine Surgery? A MSSIC Study.

BACKGROUND AND OBJECTIVES: Diabetes mellitus is associated with increased risk of postoperative adverse outcomes. Previous studies have emphasized the role of glycemic control in postoperative complications. This study aims to ascertain whether controlling hemoglobin A1c (HbA1c) lower than 8% preoperatively results in meaningful risk reduction or improved outcomes. METHODS: We used patient-level data from the Michigan Spine Surgery Improvement Collaborative registry, focusing on patients who underwent elective lumbar spine surgery between 2018 and 2021. The primary outcomes were length of stay and the occurrence of postoperative adverse events. Secondary outcomes included patient satisfaction, achievement of a minimum clinically important difference (MCID) of Patient-Reported Outcomes Measurement Information System-Physical Function, the EuroQol-5D and NRS of leg and back pain, and return to work. RESULTS: A total of 11 348 patients were included in this analysis. Patients with HbA1c above the thresholds before surgery had significantly higher risks of urinary retention for all 3 possible threshold values (incidence rate ratio [IRR] = 1.30, P = .015; IRR = 1.35, P = .001; IRR = 1.25, P = .011 for the HbA1c cutoffs of 8%, 7.5%, and 7%, respectively). They also had longer hospital stay (IRR = 1.04, P = .002; IRR = 1.03, P = .001; IRR = 1.03, P < .001 for the HbA1c cutoffs of 8%, 7.5%, and 7%, respectively) and had higher risks of developing any complication with HbA1c cutoff of 7.5% (IRR = 1.09, P = .010) and 7% (IRR = 1.12, P = .001). Diabetics with preoperative HbA1c above all 3 thresholds were less likely to achieve Patient-Reported Outcomes Measurement Information System MCID at the 90-day follow-up (IRR = .81, P < .001; IRR = .86, P < .001; IRR = .90, P = .007 for the HbA1c cutoffs of 8%, 7.5%, and 7%, respectively) and less likely to achieve EuroQol-5D MCID at the 2-year follow-up (IRR = .87, P = .027; IRR = .84, P = .005 for the HbA1c cutoffs of 7.5% and 7%, respectively). CONCLUSION: Our study suggests that reducing HbA1c below 8% may have diminishing returns regarding reducing complications after spine surgery.

Risk factors for not reaching minimal clinically important difference at 90 days and 1 year after elective lumbar spine surgery: a cohort study.

OBJECTIVE: Patient-perceived functional improvement is a core metric in lumbar surgery for degenerative disease. It is important to identify both modifiable and nonmodifiable risk factors that can be evaluated and possibly optimized prior to elective surgery. This case-control study was designed to study risk factors for not achieving the minimal clinically important difference (MCID) in Patient-Reported Outcomes Measurement Information System Function 4-item Short Form (PROMIS PF) score. METHODS: The authors queried the Michigan Spine Surgery Improvement Collaborative database to identify patients who underwent elective lumbar surgical procedures with PROMIS PF scores. Cases were divided into two cohorts based on whether patients achieved MCID at 90 days and 1 year after surgery. Patient characteristics and operative details were analyzed as potential risk factors. RESULTS: The authors captured 10,922 patients for 90-day follow-up and 4453 patients (40.8%) did not reach MCID. At the 1-year follow-up period, 7780 patients were identified and 2941 patients (37.8%) did not achieve MCID. The significant demographic characteristic-adjusted relative risks (RRs) for both groups (RR 90 day, RR 1 year) included the following: symptom duration > 1 year (1.34, 1.41); previous spine surgery (1.25, 1.30); African American descent (1.25, 1.20); chronic opiate use (1.23, 1.25); and less than high school education (1.20, 1.34). Independent ambulatory status (0.83, 0.88) and private insurance (0.91, 0.85) were associated with higher likelihood of reaching MCID at 90 days and 1 year, respectively. CONCLUSIONS: Several key unique demographic risk factors were identified in this cohort study that precluded optimal postoperative functional outcomes after elective lumbar spine surgery. With this information, appropriate preoperative counseling can be administered to assist in shaping patient expectations.

The Duration of Symptoms Influences Outcomes After Lumbar Microdiscectomies: A Michigan Spine Surgery Improvement Collaborative.

STUDY DESIGN: Retrospective Cohort. OBJECTIVE: We investigate whether duration of symptoms a patient experiences prior to lumbar microdiscectomy affects pain, lifestyle, and return to work metrics after surgery. METHODS: A retrospective review of patients with a diagnosis of lumbar radiculopathy undergoing microdiscectomy was conducted using a statewide registry. Patients were grouped based on self-reported duration of symptoms prior to surgical intervention (Group 1: symptoms less than 3 months; Group 2: symptoms between 3 months and 1 year; and Group 3: symptoms greater than 1 year). Radicular pain scores, PROMIS PF Physical Function measure (PROMIS PF), EQ-5D scores, and return to work rates at 90 days, 1 year, and 2 years after surgery were compared using univariate and multivariate analysis. RESULTS: There were 2408 patients who underwent microdiscectomy for lumbar disc herniation for radiculopathy with 532, 910, and 955 in Groups 1, 2, and 3, respectively. Postoperative leg pain was lower for Group 1 at 90 days, 1 year, and 2 years compared to Groups 2 and 3 (P < .05). Postoperative PROMIS PF and EQ-5D scores were higher for Group 1 at 90 days, 1 year, and 2 years compared to Groups 2 and 3 (P < .05). CONCLUSION: Patients with prolonged symptoms prior to surgical intervention experience smaller improvements in postoperative leg pain, PROMIS PF, and EQ-5D than those who undergo surgery earlier. Patients undergoing surgery within 3 months of symptom onset have the highest rates of return to work at 1 year after surgery.

Association of prolonged symptom duration with poor outcomes in lumbar spine surgery: a Michigan Spine Surgery Improvement Collaborative study.

OBJECTIVE: There is a scarcity of large multicenter data on how preoperative lumbar symptom duration relates to postoperative patient-reported outcomes (PROs). The objective of this study was to determine the effect of preoperative and baseline symptom duration on PROs at 90 days, 1 year, and 2 years after lumbar spine surgery. METHODS: The Michigan Spine Surgery Improvement Collaborative registry was queried for all lumbar spine operations between January 1, 2017, to December 31, 2021, with a follow-up of 2 years. Patients were stratified into three subgroups based on symptom duration: < 3 months, 3 months to < 1 year, and ≥ 1 year. The primary outcomes were reaching the minimal clinically important difference (MCID) for the PROs (i.e., leg pain, Patient-Reported Outcomes Measurement Information System Physical Function (PROMIS PF), EQ-5D, North American Spine Society satisfaction, and return to work). The EQ-5D score was also analyzed as a continuous variable to calculate quality-adjusted life years. Multivariable Poisson generalized estimating equation models were used to report adjusted risk ratios, with the < 3-month cohort used as the reference. RESULTS: There were 37,223 patients (4670 with < 3-month duration, 9356 with 3-month to < 1-year duration, and 23,197 with ≥ 1-year duration) available for analysis. Compared with patients with a symptom duration of < 1 year, patients with a symptom duration of ≥ 1 year were significantly less likely to achieve an MCID in PROMIS PF, EQ-5D, back pain relief, and leg pain relief at 90 days, 1 year, and 2 years postoperatively. Similar trends were observed for patient satisfaction and return to work. With the EQ-5D score as a continuous variable, a symptom duration of ≥ 1 year was associated with 0.04, 0.05, and 0.03 (p < 0.001) decreases in EQ-5D score at 90 days, 1 year, and 2 years after surgery, respectively. CONCLUSIONS: A symptom duration of ≥ 1 year was associated with poorer outcomes on several outcome metrics. This suggests that timely referral and surgery for degenerative lumbar pathology may optimize patient outcome.

The Potential Negative Effects of Smoking on Cervical and Lumbar Surgery Beyond Pseudarthrosis: A Michigan Spine Surgery Improvement Collaborative Study.

OBJECTIVE: To review the Michigan Spine Surgery Improvement Collaborative registry to investigate the long-term associations between current smoking status and outcomes after elective cervical and lumbar spine surgery. METHODS: Using the Michigan Spine Surgery Improvement Collaborative, we captured all cases from January 1, 2017, to November 21, 2020, with outcomes data available; 19,251 lumbar cases and 7936 cervical cases were included. Multivariate regression analyses were performed to assess the relationship of smoking with the clinical outcomes. RESULTS: Current smoking status was associated with lower urinary retention and satisfaction for patients after lumbar surgery and was associated with less likelihood of achieving minimal clinically important difference in primary outcome measures including Patient-Reported Outcomes Measurement Information System, back pain, leg pain, and EuroQol-5D at 90 days and 1 year after surgery. Current smokers were also less likely to return to work at 90 days and 1 year after surgery. Among patients who underwent cervical surgery, current smokers were less likely to have urinary retention and dysphagia postoperatively. They were less likely to be satisfied with the surgery outcome at 1 year. Current smoking was associated with lower likelihood of achieving minimal clinically important difference in Patient-Reported Outcomes Measurement Information System, neck pain, arm pain, and EuroQol-5D at various time points. There was no difference in return-to-work status. CONCLUSIONS: Our analysis suggests that smoking is negatively associated with functional improvement, patient satisfaction, and return-to-work after elective spine surgery.

Postoperative opioid prescription and patient-reported outcomes after elective spine surgery: a Michigan Spine Surgery Improvement Collaborative study.

OBJECTIVE: This study was designed to assess how postoperative opioid prescription dosage could affect patient-reported outcomes after elective spine surgery. METHODS: Patients enrolled in the Michigan Spine Surgery Improvement Collaborative (MSSIC) from January 2020 to September 2021 were included in this study. Opioid prescriptions at discharge were converted to total morphine milligram equivalents (MME). A reference value of 225 MME per week was used as a cutoff. Patients were divided into two cohorts based on prescribed total MME: ≤ 225 MME and > 225 MME. Primary outcomes included patient satisfaction, return to work status after surgery, and whether improvement of the minimal clinically important difference (MCID) of the Patient-Reported Outcomes Measurement Information System 4-question short form for physical function (PROMIS PF) and EQ-5D was met. Generalized estimated equations were used for multivariate analysis. RESULTS: Regression analysis revealed that patients who had postoperative opioids prescribed with > 225 MME were less likely to be satisfied with surgery (adjusted OR [aOR] 0.81) and achieve PROMIS PF MCID (aOR 0.88). They were also more likely to be opioid dependent at 90 days after elective spine surgery (aOR 1.56). CONCLUSIONS: The opioid epidemic is a serious threat to national public health, and spine surgeons must practice conscientious postoperative opioid prescribing to achieve adequate pain control. The authors' analysis illustrates that a postoperative opioid prescription of 225 MME or less is associated with improved patient satisfaction, greater improvement in physical function, and decreased opioid dependence compared with those who had > 225 MME prescribed.

Validation of the Benefits of Ambulation Within 8 Hours of Elective Cervical and Lumbar Surgery: A Michigan Spine Surgery Improvement Collaborative Study.

BACKGROUND: Early ambulation is considered a key element to Enhanced Recovery After Surgery protocol after spine surgery. OBJECTIVE: To investigate whether ambulation less than 8 hours after elective spine surgery is associated with improved outcome. METHODS: The Michigan Spine Surgery Improvement Collaborative database was queried to track all elective cervical and lumbar spine surgery between July 2018 and April 2021. In total, 7647 cervical and 17 616 lumbar cases were divided into 3 cohorts based on time to ambulate after surgery: (1) <8 hours, (2) 8 to 24 hours, and (3) >24 hours. RESULTS: For cervical cases, patients who ambulated 8 to 24 hours (adjusted odds ratio [aOR] 1.38; 95% CI 1.11-1.70; P = .003) and >24 hours (aOR 2.20; 95% CI 1.20-4.03; P = .011) after surgery had higher complication rate than those who ambulated within 8 hours of surgery. Similar findings were noted for lumbar cases with patients who ambulated 8 to 24 hours (aOR 1.31; 95% CI 1.12-1.54; P < .001) and >24 hours (aOR 1.96; 95% CI 1.50-2.56; P < .001) after surgery having significantly higher complication rate than those ambulated <8 hours after surgery. Analysis of secondary outcomes for cervical cases demonstrated that <8-hour ambulation was associated with home discharge, shorter hospital stay, lower 90-day readmission, and lower urinary retention rate. For lumbar cases, <8-hour ambulation was associated with shorter hospital stay, satisfaction with surgery, lower 30-day readmission, home discharge, and lower urinary retention rate. CONCLUSION: Ambulation within 8 hours after surgery is associated with significant improved outcome after elective cervical and lumbar spine surgery.

A Matched Cohort Analysis of Drain Usage in Elective Anterior Cervical Discectomy and Fusion: A Michigan Spine Surgery Improvement Collaborative (MSSIC) Study.

STUDY DESIGN: This is a retrospective, cohort analysis of multi-institutional database. OBJECTIVE: This study was designed to analyze the impact of drain use following elective anterior cervical discectomy and fusion (ACDF) surgeries. SUMMARY OF BACKGROUND DATA: After ACDF, a drain is often placed to prevent postoperative hematoma. However, there has been no high quality evidence to support its use with ACDF despite the theoretical benefits and risks of drain placement. METHODS: The Michigan Spine Surgery Improvement Collaborative database was queried to identify all patients undergoing elective ACDF between February 2014 and October 2019. Cases were divided into two cohorts based on drain use. Propensity-score matching was utilized to adjust for inherent differences between the two cohorts. Measured outcomes included surgical site hematoma, length of stay, surgical site infection, dysphagia, home discharge, readmission within 30 days, and unplanned reoperation. RESULTS: We identified 7943 patients during the study period. Propensity-score matching yielded 3206 pairs. On univariate analysis of matched cohorts, there were no differences in rate of postoperative hematoma requiring either return to OR or readmission. We noted patients with drains had a higher rate of dysphagia (4.6% vs. 6.3%; P = 0.003) and had longer hospital stay (P < 0.001). On multivariate analysis, drain use was associated with significantly increased length of stay (relative risk 1.23, 95% confidence interval [CI] 1.13-1.34; P < 0.001). There were no significant differences in other outcomes measured. CONCLUSION: Our analysis demonstrated that drain use is associated with significant longer hospital stay.Level of Evidence: 3.

Analysis of Factors Associated with Return-to-Work After Lumbar Surgery up to 2-Years Follow-up: A Michigan Spine Surgery Improvement Collaborative (MSSIC) Study.

STUDY DESIGN: Michigan Spine Surgery Improvement Collaborative (MSSIC) prospectively collects data on all patients undergoing operations for degenerative and/or deformity indications. OBJECTIVE: We aimed to identify which factors are significantly associated with return-to-work after lumbar surgery at long-term follow-up. SUMMARY OF BACKGROUND DATA: Prior publications have created a clinically relevant predictive model for return-to-work, wherein education, gender, race, comorbidities, and preoperative symptoms increased likelihood of return-to-work at 3 months after lumbar surgery. We sought to determine if these trends 1) persisted at 1 year and 2 years postoperatively; or 2) differed among preoperatively employed versus unemployed patients. METHODS: MSSIC was queried for all patients undergoing lumbar operations (2014-2019). All patients intended to return-to-work postoperatively. Patients were followed for up to 2 years postoperatively. Measures of association were calculated with multivariable generalized estimating equations. RESULTS: Return-to-work increased from 63% (3542/5591) at 90 days postoperatively to 75% (3143/4147) at 1 year and 74% (2133/2866) at 2 years postoperatively. Following generalized estimating equations, neither clinical nor surgical variables predicted return-to-work at all three time intervals: 90 days, 1 year, and 2 years postoperatively. Only socioeconomic factors reached statistical significance at all follow-up points. Preoperative employment followed by insurance status had the greatest associations with return-to-work. In a subanalysis of patients who were preoperatively employed, insurance was the only factor with significant associations with return-to-work at all three follow-up intervals. The return-to-work rates among unemployed patients at baseline increased from 29% (455/1100) at 90 days, 44% (495/608) at 1 year, and 46% (366/426) at 2 years postoperatively. The only two significant factors associated with return-to-work at all three follow-up intervals were Medicaid, as compared with private insurance, and male gender. CONCLUSION: In patients inquiring about long-term return-to-work after lumbar surgery, insurance status represents the important determinant of employment status.Level of Evidence: 2.

The association of patient education level with outcomes after elective lumbar surgery: a Michigan Spine Surgery Improvement Collaborative study.

OBJECTIVE: Socioeconomic factors have been shown to impact a host of healthcare-related outcomes. Level of education is a marker of socioeconomic status. This study aimed to investigate the relationship between patient education level and outcomes after elective lumbar surgery and to characterize any education-related disparities. METHODS: The Michigan Spine Surgery Improvement Collaborative registry was queried for all lumbar spine operations. Primary outcomes included patient satisfaction determined by the North American Spine Society patient satisfaction index, and reaching the minimum clinically important difference of Patient-Reported Outcomes Measurement Information System Physical Function score and return to work up to 2 years after surgery. Multivariate Poisson generalized estimating equation models reported adjusted risk ratios. RESULTS: A total of 26,229 lumbar spine patients had data available for inclusion in this study. On multivariate generalized estimating equation analysis all comparisons were done versus the high school (HS)/general equivalency development (GED)-level cohort. For North American Spine Society satisfaction scores after surgery the authors observed the following: at 90 days the likelihood of satisfaction significantly decreased by 11% (p < 0.001) among < HS, but increased by 1% (p = 0.52) among college-educated and 3% (p = 0.011) among postcollege-educated cohorts compared to the HS/GED cohort; at 1 year there was a decrease of 9% (p = 0.02) among < HS and increases of 3% (p = 0.02) among college-educated and 9% (p < 0.001) among postcollege-educated patients; and at 2 years, there was an increase of 5% (p = 0.001) among postcollege-educated patients compared to the < HS group. The likelihood of reaching a minimum clinically important difference of Patient-Reported Outcomes Measurement Information System Physical Function score at 90 days increased by 5% (p = 0.005) among college-educated and 9% (p < 0.001) among postcollege-educated cohorts; at 1 year, all comparison cohorts demonstrated significance, with a decrease of 12% (p = 0.007) among < HS, but an increase by 6% (p < 0.001) among college-educated patients and 14% (p < 0.001) among postcollege-educated compared to the HS/GED cohort; at 2 years, there was a significant decrease by 19% (p = 0.003) among the < HS cohort, an increase by 8% (p = 0.001) among the college-educated group, and an increase by 16% (p < 0.001) among the postcollege-educated group. For return to work, a significant increase was demonstrated at 90 days and 1 year when comparing the HS or less group with college or postcollege cohorts. CONCLUSIONS: This study demonstrated negative associations on all primary outcomes with lower levels of education. This finding suggests a potential disparity linked to education in elective spine surgery.

Preoperative HbA1c > 8% Is Associated With Poor Outcomes in Lumbar Spine Surgery: A Michigan Spine Surgery Improvement Collaborative Study.

BACKGROUND: Preoperative hemoglobin A1c (HbA1c) is a useful screening tool since a significant portion of diabetic patients in the United States are undiagnosed and the prevalence of diabetes continues to increase. However, there is a paucity of literature analyzing comprehensive association between HbA1c and postoperative outcome in lumbar spine surgery. OBJECTIVE: To assess the prognostic value of preoperative HbA1c > 8% in patients undergoing elective lumbar spine surgery. METHODS: The Michigan Spine Surgery Improvement Collaborative (MSSIC) database was queried to track all elective lumbar spine surgeries between January 2018 and December 2019. Cases were divided into 2 cohorts based on preoperative HbA1c level (≤8% and >8%). Measured outcomes include any complication, surgical site infection (SSI), readmission (RA) within 30 d (30RA) and 90 d (90RA) of index operation, patient satisfaction, and the percentage of patients who achieved minimum clinically important difference (MCID) using Patient-Reported Outcomes Measurement Information System. RESULTS: We captured 4778 patients in this study. Our multivariate analysis demonstrated that patients with HbA1c > 8% were more likely to experience postoperative complication (odds ratio [OR] 1.81, 95% CI 1.20-2.73; P = .005) and be readmitted within 90 d of index surgery (OR 1.66, 95% CI 1.08-2.54; P = .021). They also had longer hospital stay (OR 1.12, 95% CI 1.03-1.23; P = .009) and were less likely to achieve functional improvement after surgery (OR 0.64, 95% CI 0.44-0.92; P = .016). CONCLUSION: HbA1c > 8% is a reliable predictor of poor outcome in elective lumbar spine surgery. Clinicians should consider specialty consultation to optimize patients' glycemic control prior to surgery.

Age as a Predictor for Complications and Patient-reported Outcomes in Multilevel Transforaminal Lumbar Interbody Fusions: Analyses From the Michigan Spine Surgery Improvement Collaborative (MSSIC).

STUDY DESIGN: Retrospective review of a multi-institutional data registry. OBJECTIVE: The authors sought to determine the association between age and complications & patient-reported outcomes (PRO) in patients undergoing multilevel transforaminal interbody lumbar fusion (MTLIF). SUMMARY OF BACKGROUND DATA: Elderly patients undergoing MTLIF are considered high risk. However, data on complications and PRO are lacking. Additionally, safety of multilevel lumbar fusion in the elderly remains uncertain. METHODS: Patients ≥50-year-old who underwent MTLIF for degenerative lumbar spine conditions were analyzed. Ninety-day complications and PROs (baseline, 90-d, 1-y, 2-y) were queried using the MSSIC database. PROs were measured by back & leg visual analog scale (VAS), Patient-reported Outcomes Measurement Information System (PROMIS), EuroQol-5D (EQ-5D), and North American Spine Society (NASS) Patient Satisfaction Index. Univariate analyses were used to compare among elderly and complication cohorts. Generalized estimating equation (GEE) was used to identify predictors of complications and PROs. RESULTS: A total of 3120 patients analyzed with 961 (31%) ≥ 70-y-o and 2159 (69%) between 50-69. A higher proportion of elderly experienced postoperative complications (P = .003) including urinary retention (P = <.001) and urinary tract infection (P = .002). Multivariate analysis demonstrated that age was not independently associated with complications. Number of operative levels was associated with any (P = .001) and minor (P = .002) complication. Incurring a complication was independently associated with worse leg VAS and PROMIS scores (P = <.001). Preoperative independent ambulation was independently associated with improved PROMIS, and EQ5D (P = <.001). Within the elderly, preoperative independent ambulation and lower BMI were associated with improved PROMIS (P = <.001). Complications had no significant effect on PROs in the elderly. CONCLUSIONS: Age was not associated with complications nor predictive of functional outcomes in patients who underwent MTLIF. Age alone, therefore, may not be an appropriate surrogate for risk. Furthermore, baseline preoperative independent ambulation was associated with better clinical outcomes and should be considered during preoperative surgical counseling.Level of Evidence: 3.

Site-specific characterization of SARS-CoV-2 spike glycoprotein receptor-binding domain.

The novel coronavirus SARS-CoV-2, the infective agent causing COVID-19, is having a global impact both in terms of human disease as well as socially and economically. Its heavily glycosylated spike glycoprotein is fundamental for the infection process, via its receptor-binding domains interaction with the glycoprotein angiotensin-converting enzyme 2 on human cell surfaces. We therefore utilized an integrated glycomic and glycoproteomic analytical strategy to characterize both N- and O- glycan site-specific glycosylation within the receptor-binding domain. We demonstrate the presence of complex-type N-glycans with unusual fucosylated LacdiNAc at both sites N331 and N343 and a single site of O-glycosylation on T323.

Impact of Michigan's new opioid prescribing laws on spine surgery patients: analysis of the Michigan Spine Surgery Improvement Collaborative.

OBJECTIVE: In 2017, Michigan passed new legislation designed to reduce opioid abuse. This study evaluated the impact of these new restrictive laws on preoperative narcotic use, short-term outcomes, and readmission rates after spinal surgery. METHODS: Patient data from 1 year before and 1 year after initiation of the new opioid laws (beginning July 1, 2018) were queried from the Michigan Spine Surgery Improvement Collaborative database. Before and after implementation of the major elements of the new laws, 12,325 and 11,988 patients, respectively, were treated. RESULTS: Patients before and after passage of the opioid laws had generally similar demographic and surgical characteristics. Notably, after passage of the opioid laws, the number of patients taking daily narcotics preoperatively decreased from 3783 (48.7%) to 2698 (39.7%; p < 0.0001). Three months postoperatively, there were no differences in minimum clinically important difference (56.0% vs 58.0%, p = 0.1068), numeric rating scale (NRS) score of back pain (3.5 vs 3.4, p = 0.1156), NRS score of leg pain (2.7 vs 2.7, p = 0.3595), satisfaction (84.4% vs 84.7%, p = 0.6852), or 90-day readmission rate (5.8% vs 6.2%, p = 0.3202) between groups. Although there was no difference in readmission rates, pain as a reason for readmission was marginally more common (0.86% vs 1.22%, p = 0.0323). CONCLUSIONS: There was a meaningful decrease in preoperative narcotic use, but notably there was no apparent negative impact on postoperative recovery, patient satisfaction, or short-term outcomes after spinal surgery despite more restrictive opioid prescribing. Although the readmission rate did not significantly increase, pain as a reason for readmission was marginally more frequently observed.

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 CONTEXT: Hospital 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. PURPOSE: We 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 DESIGN: Retrospective review of prospectively collected database PATIENT SAMPLE: Michigan Spine Surgery Improvement Collaborative (MSSIC) registry OUTCOME MEASURES: Hospital readmission at 90 days METHODS: The 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. RESULTS: Of 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%). CONCLUSIONS: Analysis 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.

The Preoperative Risks and Two-Year Sequelae of Postoperative Urinary Retention: Analysis of the Michigan Spine Surgery Improvement Collaborative (MSSIC).

OBJECTIVE: Although postoperative urinary retention (POUR) is common after spine surgery, the association of this adverse event with other morbidities and patient-reported outcomes is not fully understood. We sought to examine the sequelae of POUR after lumbar spine surgery. METHODS: The Michigan Spine Surgery Improvement Collaborative (MSSIC) is a large prospective multicenter registry. MSSIC was queried with multivariate analysis for factors that are associated with POUR, the association of POUR with 90-day adverse events, and the effect of POUR on 2-year patient-reported outcomes and satisfaction. RESULTS: Multivariate analysis identified hardware revision (odds ratio [OR], 0.61), 1 operative level (OR, 0.74), and ambulation on postoperative day zero (OR, 0.65) to be protective for POUR. Factors associated with POUR included age (OR, 1.19), male gender (OR, 1.58), body mass index <25 (OR, 1.22), diabetes (OR, 1.28), coronary artery disease (OR, 1.20), fusion surgery (OR, 1.27), and longer surgery (OR, 1.11). Patients who had POUR were more likely to be readmitted, develop a urinary tract infection, and develop an infection (P < 0.001). POUR was associated with decreased likelihood of achieving Oswestry Disability Index minimal clinically important difference at 90 days (P < 0.001), but not at 1 year after surgery. POUR was associated with dissatisfaction with surgery at 90 days (P < 0.001), 1 year (P = 0.004), and 2 years after surgery (P = 0.011). CONCLUSIONS: POUR is common after lumbar spine surgery, and the demographic, diagnostic, and surgical factors that are associated with POUR are identified. POUR is associated with several adverse events, and patients who have POUR were less likely to be satisfied with surgery up to 2 years after surgery.

The Association of Preoperative Opioid Usage With Patient-Reported Outcomes, Adverse Events, and Return to Work After Lumbar Fusion: Analysis From the Michigan Spine Surgery Improvement Collaborative (MSSIC).

BACKGROUND: It is important to delineate the relationship between opioid use and spine surgery outcomes. OBJECTIVE: To determine the association between preoperative opioid usage and postoperative adverse events, patient satisfaction, return to work, and improvement in Oswestry Disability Index (ODI) in patients undergoing lumbar fusion procedures by using 2-yr data from a prospective spine registry. METHODS: Preoperative opioid chronicity from 8693 lumbar fusion patients was defined as opioid-naïve (no usage), new users (<6 wk), short-term users (6 wk-3 mo), intermediate-term users (3-6 mo), and chronic users (>6 mo). Multivariate generalized estimating equation models were constructed. RESULTS: All comparisons were to opioid-naïve patients. Chronic opioid users showed less satisfaction with their procedure at 90 d (Relative Risk (RR) 0.95, P = .001), 1 yr (RR 0.89, P = .001), and 2 yr (RR 0.89, P = .005). New opioid users were more likely to show improvement in ODI at 90 d (RR 1.25, P < .001), 1 yr (RR 1.17, P < .001), and 2 yr (RR 1.19, P = .002). Short-term opioid users were more likely to show ODI improvement at 90 d (RR 1.25, P < .001). Chronic opioid users were less likely to show ODI improvement at 90 d (RR 0.90, P = .004), 1 yr (RR 0.85, P < .001), and 2 yr (RR 0.80, P = .003). Chronic opioid users were less likely to return to work at 90 d (RR 0.80, P < .001). CONCLUSION: In lumbar fusion patients and when compared to opioid-naïve patients, new opioid users were more likely and chronic opioid users less likely to have improved ODI scores 2 yr after surgery. Chronic opioid users are less likely to be satisfied with their procedure 2 yr after surgery and less likely to return to work at 90 d. Preoperative opioid counseling is advised.

Effect of Tanezumab on Joint Pain, Physical Function, and Patient Global Assessment of Osteoarthritis Among Patients With Osteoarthritis of the Hip or Knee: A Randomized Clinical Trial.

Importance: Patients with osteoarthritis (OA) may remain symptomatic with traditional OA treatments. Objective: To assess 2 subcutaneous tanezumab dosing regimens for OA. Design, Setting, and Participants: A randomized, double-blind, multicenter trial from January 2016 to May 14, 2018 (last patient visit). Patients enrolled were 18 years or older with hip or knee OA, inadequate response to OA analgesics, and no radiographic evidence of prespecified joint safety conditions. Interventions: Patients received by subcutaneous administration either tanezumab, 2.5 mg, at day 1 and week 8 (n = 231); tanezumab, 2.5 mg at day 1 and 5 mg at week 8 (ie, tanezumab, 2.5/5 mg; n = 233); or placebo at day 1 and week 8 (n = 232). Main Outcomes and Measures: Co-primary end points were change from baseline to week 16 in Western Ontario and McMasters Universities Osteoarthritis Index (WOMAC) Pain (0-10, no to extreme pain), WOMAC Physical Function (0-10, no to extreme difficulty), and patient global assessment of osteoarthritis (PGA-OA) (1-5, very good to very poor) scores. Results: Among 698 patients randomized, 696 received 1 or more treatment doses (mean [SD] age, 60.8 [9.6] years; 65.1% women), and 582 (83.6%) completed the trial. From baseline to 16 weeks, mean WOMAC Pain scores decreased from 7.1 to 3.6 in the tanezumab, 2.5 mg, group; 7.3 to 3.6 in the tanezumab, 2.5/5 mg, group; and 7.3 to 4.4 in the placebo group (least squares mean differences [95% CI] vs placebo were -0.60 [-1.07 to -0.13; P = .01] for tanezumab, 2.5 mg, and -0.73 [-1.20 to -0.26; P = .002] for tanezumab, 2.5/5 mg). Mean WOMAC Physical Function scores decreased from 7.2 to 3.7 in the 2.5-mg group, 7.4 to 3.6 in the 2.5/5-mg group, and 7.4 to 4.5 with placebo (differences vs placebo, -0.66 [-1.14 to -0.19; P = .007] for tanezumab, 2.5 mg, and -0.89 [-1.37 to -0.42; P < .001] for tanezumab, 2.5/5 mg). Mean PGA-OA scores decreased from 3.4 to 2.4 in the 2.5-mg group, 3.5 to 2.4 in the 2.5/5-mg group, and 3.5 to 2.7 with placebo (differences vs placebo, -0.22 [-0.39 to -0.05; P = .01] for tanezumab, 2.5 mg, and -0.25 [-0.41 to -0.08; P = .004] for tanezumab, 2.5/5 mg). Rapidly progressive OA occurred only in tanezumab-treated patients (2.5 mg: n = 5, 2.2%; 2.5/5 mg: n = 1, 0.4%). The incidence of total joint replacements was 8 (3.5%), 16 (6.9%), and 4 (1.7%) in the tanezumab, 2.5 mg; tanezumab, 2.5/5 mg; and placebo groups, respectively. Conclusions and Relevance: Among patients with moderate to severe OA of the knee or hip and inadequate response to standard analgesics, tanezumab, compared with placebo, resulted in statistically significant improvements in scores assessing pain and physical function, and in PGA-OA, although the improvements were modest and tanezumab-treated patients had more joint safety events and total joint replacements. Further research is needed to determine the clinical importance of these efficacy and adverse event findings. Trial Registration: ClinicalTrials.gov Identifier: NCT02697773.