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.

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.

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.

Correlation of mJOA, PROMIS physical function, and patient satisfaction in patients with cervical myelopathy: an analysis of the Michigan Spine Surgery Improvement Collaborative (MSSIC) database.

BACKGROUND CONTEXT: Patient-reported outcomes (PROs) are increasingly utilized to evaluate the efficacy and value of spinal procedures. Among patients with cervical myelopathy, the modified Japanese Orthopaedic Association (mJOA) remains the standard instrument, with Patient-Reported Outcomes Measurement Information System (PROMIS) physical function (PF) and patient satisfaction also frequently assessed. These outcomes have not all been directly compared using a large spine registry at 2 years follow-up for cervical myelopathic patients undergoing surgery. PURPOSE: To determine the correlation and association of PROMIS PF, mJOA, and patient satisfaction outcomes in patients undergoing surgery for cervical myelopathy. STUDY DESIGN/SETTING: Retrospective review of a multicenter spine registry database. PATIENT SAMPLE: Adult patients with cervical myelopathy who underwent cervical spine surgery between 2/26/2018 and 4/17/2021. OUTCOME MEASURES: PROMIS PF, mJOA, and North American Spine Society (NASS) patient satisfaction index. METHODS: The MSSIC database was accessed to gather pre- and postoperative outcome data on patients with cervical myelopathy. Spearman's correlation coefficients relating mJOA and PROMIS PF were quantified up to 2 years postoperatively. The correlations between patient satisfaction with mJOA and PROMIS were determined. Kappa statistics were used to evaluate for agreement between those reaching the minimum clinically important difference (MCID) for mJOA and PROMIS PF. Odds ratios were calculated to determine the association between patient satisfaction and those reaching MCID for mJOA and PROMIS PF. Support for MSSIC is provided by BCBSM and Blue Care Network as part of the BCBSM Value Partnerships program. RESULTS: Data from 2,023 patients were included. Moderate to strong correlations were found between mJOA and PROMIS PF at all time points (p<.001). These outcomes had fair agreement at all postoperative time points when comparing those who reached MCID. Satisfaction was strongly related to changes from baseline for both mJOA and PROMIS PF at all time points (p<.001). Odds ratios associating satisfaction with PROMIS PF MCID were higher at all time points compared with mJOA, although the differences were not significant. CONCLUSIONS: PROMIS PF has a strong positive correlation with mJOA up to 2 years postoperatively in patients undergoing surgery for cervical myelopathy, with similar odds of achieving MCID with both instruments. Patient satisfaction is predicted similarly by these outcome measures by 2 years postoperatively. These results affirm the validity of PROMIS PF in the cervical myelopathic population. Given its generalizability and ease of use, PROMIS PF may be a more practical outcome measure for clinical use compared with mJOA.

Rates and reasons for reoperation within 30 and 90 days following cervical spine surgery: a retrospective cohort analysis of the Michigan Spine Surgery Improvement Collaborative (MSSIC) registry.

BACKGROUND CONTEXT: Reoperation following cervical spinal surgery negatively impacts patient outcomes and increases health care system burden. To date, most studies have evaluated reoperations within 30 days after spine surgery and have been limited in scope and focus. Evaluation within the 90-day period, however, allows a more comprehensive assessment of factors associated with reoperation. PURPOSE: The purpose of this study is to assess the rates and reasons for reoperations after cervical spine surgery within 30 and 90 days. DESIGN: We performed a retrospective analysis of a state-wide prospective, multi-center, spine-specific database of patients surgically treated for degenerative disease. PATIENT SAMPLE: Patients 18 years of age or older who underwent cervical spine surgery for degenerative pathologies from February 2014 to May 2019. Operative criteria included all degenerative cervical spine procedures, including those with cervical fusions with contiguous extension down to T3. OUTCOME MEASURES: We determined causes for reoperation and independent surgical and demographic risk factors impacting reoperation. METHODS: Patient-specific and surgery-specific data was extracted from the registry using ICD-10-DM codes. Reoperations data was obtained through abstraction of medical records through 90 days. Univariate analysis was done using chi-square tests for categorical variables, t-tests for normally distributed variables, and Wilcoxon rank-sum tests for variables with skewed distributions. Odds ratios for return to the operating room (OR) were evaluated in multivariate analysis. RESULTS: A total of 13,435 and 13,440 patients underwent cervical spine surgery and were included in the 30 and 90-day analysis, respectively. The overall reoperation rate was 1.24% and 3.30% within 30 and 90 days, respectively. Multivariate analysis showed within 30 days, procedures involving four or more levels, posterior only approach, and longer length of stay had increased odds of returning to the OR (p<.05), whereas private insurance had a decreased odds of return to OR (p<.05). Within 90 days, male sex, coronary artery disease (CAD), previous spine surgery, procedures with 4 or more levels, and longer length of stay had significantly increased odds of returning to the OR (p<.05). Non-white race, independent ambulatory status pre-operatively, and having private insurance had decreased odds of return to the OR (p<.05). The most common specified reasons for return to the OR within 30 days was hematoma (19%), infection (17%), and wound dehiscence (11%). Within 90 days, reoperation reasons were pain (10%), infection (9%), and hematoma (8%). CONCLUSION: Reoperation rates after elective cervical spine surgery are 1.24% and 3.30% within 30 and 90 days, respectively. Within 30 days, four or more levels, posterior approach, and longer length of stay were risk factors for reoperation. Within 90 days, male sex, CAD, four or more levels, and longer length of hospital stay were risk factors for reoperation. Non-white demographic and independent preoperative ambulatory status were associated with decreased reoperation rates.

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.

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.

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.

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.

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.

Disparities in outcomes after spine surgery: a Michigan Spine Surgery Improvement Collaborative study.

OBJECTIVE: Most studies on racial disparities in spine surgery lack data granularity to control for both comorbidities and self-assessment metrics. Analyses from large, multicenter surgical registries can provide an enhanced platform for understanding different factors that influence outcome. In this study, the authors aimed to determine the effects of race on outcomes after lumbar surgery, using patient-reported outcomes (PROs) in 3 areas: the North American Spine Society patient satisfaction index, the minimal clinically important difference (MCID) on the Oswestry Disability Index (ODI) for low-back pain, and return to work. METHODS: The Michigan Spine Surgery Improvement Collaborative was queried for all elective lumbar operations. Patient race/ethnicity was categorized as Caucasian, African American, and "other." Measures of association between race and PROs were calculated with generalized estimating equations (GEEs) to report adjusted risk ratios. RESULTS: The African American cohort consisted of a greater proportion of women with the highest comorbidity burden. Among the 7980 and 4222 patients followed up at 1 and 2 years postoperatively, respectively, African American patients experienced the lowest rates of satisfaction, MCID on ODI, and return to work. Following a GEE, African American race decreased the probability of satisfaction at both 1 and 2 years postoperatively. Race did not affect return to work or achieving MCID on the ODI. The variable of greatest association with all 3 PROs at both follow-up times was postoperative depression. CONCLUSIONS: While a complex myriad of socioeconomic factors interplay between race and surgical success, the authors identified modifiable risk factors, specifically depression, that may improve PROs among African American patients after elective lumbar spine surgery.

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.

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.

Patient Demographic and Surgical Factors that Affect Completion of Patient-Reported Outcomes 90 Days and 1 Year After Spine Surgery: Analysis from the Michigan Spine Surgery Improvement Collaborative (MSSIC).

BACKGROUND: The Michigan Spine Surgery Improvement Collaborative is a statewide multicenter quality improvement registry. Because missing data can affect registry results, we used MSSIC to find demographic and surgical characteristics that affect the completion of patient-reported outcomes (PROs) at 90 days and 1 year. METHODS: A total of 24,404 patients who had lumbar surgery (17,813 patients) or cervical surgery (6591 patients) were included. Multivariate logistic regression models of patient disease were constructed to identify risk factors for failure to complete scheduled PRO surveys. RESULTS: Patients ≥65 years old and female patients were both more likely to respond at 90 days and 1 year. Increasing education was associated with greater response rate at 90 days and 1 year. Whites and African Americans had no differences in response rates. Calling provided the highest response rate at 90 days and 1 year. For cervical spine patients, only discharge to rehabilitation increased completion rates, at 90 days but not 1 year. For lumbar spine patients, spondylolisthesis or stenosis (vs. herniated disc) had a greater response rate at 1 year. Patients with leg (vs. back) pain had a greater response only at 1 year. Patients with multilevel surgery had an increased response at 1 year. Patients who underwent fusion were more likely to respond at 90 days, but not 1 year. Discharge to rehabilitation increased response at 90 days and 1 year. CONCLUSIONS: A multivariate analysis from a multicenter prospective database identified surgical factors that affect PRO follow-up, up to 1 year. This information can be helpful for imputing missing PRO data and could be used to strengthen data derived from large prospective databases.

Chondrogenic derivatives of embryonic stem cells seeded into 3D polycaprolactone scaffolds generated cartilage tissue in vivo.

In spite of recent scientific advances, treatment and repair of cartilage using tissue engineering techniques remains challenging. The major constraint is the limited proliferative capacity of mature autologous chondrocytes used in the tissue engineering approach. This problem can be addressed by using stem cells, which can self-renew with greater proliferative potential. Cartilage tissue engineering using adult mesenchymal stem cells derived from bone marrows has met with limited success. In this study we explored cartilage tissue generation from embryonic stem cells (ESCs). ESCs were induced to differentiate into chondroprogenitors, capable of proliferating and subsequently differentiating into cartilage-producing cells. The chondrogenic cells expressed chondrocyte-specific markers and deposited extracellular matrix proteins, proteoglycans. ESC-derived chondrogenic cells and polycaprolactone scaffolds seeded with these cells implanted in mice (129 SvImJ) generated cartilage tissue in vivo. Postimplant analysis of the retrieved tissues demonstrated cartilage-like tissue formation in 3-4 weeks. The cells of retrieved tissues also expressed the chondrocyte-specific marker collagen II. These findings suggest that ESCs can be used for tissue engineering and cultivation of cartilage tissues.