What predicts the best 24-month outcomes following surgery for cervical spondylotic myelopathy? A QOD prospective registry study.

OBJECTIVE: The aim of this study was to identify predictors of the best 24-month improvements in patients undergoing surgery for cervical spondylotic myelopathy (CSM). For this purpose, the authors leveraged a large prospective cohort of surgically treated patients with CSM to identify factors predicting the best outcomes for disability, quality of life, and functional status following surgery. METHODS: This was a retrospective analysis of prospectively collected data. The Quality Outcomes Database (QOD) CSM dataset (1141 patients) at 14 top enrolling sites was used. Baseline and surgical characteristics were compared for those reporting the top and bottom 20th percentile 24-month Neck Disability Index (NDI), EuroQol-5D (EQ-5D), and modified Japanese Orthopaedic Association (mJOA) change scores. A multivariable logistic model was constructed and included candidate variables reaching p ≤ 0.20 on univariate analyses. Least important variables were removed in a stepwise manner to determine the significant predictors of the best outcomes (top 20th percentile) for 24-month NDI, EQ-5D, and mJOA change. RESULTS: A total of 948 (83.1%) patients with 24-month follow-up were included in this study. For NDI, 204 (17.9%) had the best NDI outcome and 200 (17.5%) had the worst NDI outcome. Factors predicting the best NDI outcomes included symptom duration less than 12 months (OR 1.5, 95% CI 1.1-1.9; p = 0.01); procedure other than posterior fusion (OR 1.5, 95% CI 1.03-2.1; p = 0.03); higher preoperative visual analog scale neck pain score (OR 1.2, 95% CI 1.1-1.3; p < 0.001); and higher baseline NDI (OR 1.06, 95% CI 1.05-1.07; p < 0.001). For EQ-5D, 163 (14.3%) had the best EQ-5D outcome and 169 (14.8%) had the worst EQ-5D outcome. Factors predicting the best EQ-5D outcomes included arm pain-only complaints (compared to neck pain) (OR 1.9, 95% CI 1.3-2.9; p = 0.002) and lower baseline EQ-5D (OR 167.7 per unit lower, 95% CI 85.0-339.4; p < 0.001). For mJOA, 222 (19.5%) had the best mJOA outcome and 238 (20.9%) had the worst mJOA outcome. Factors predicting the best mJOA outcomes included lower BMI (OR 1.03 per unit lower, 95% CI 1.004-1.05; p = 0.02; cutoff value of ≤ 29.5 kg/m2); arm pain-only complaints (compared to neck pain) (OR 1.7, 95% CI 1.1-2.5; p = 0.02); and lower baseline mJOA (OR 1.6 per unit lower, 95% CI 1.5-1.7; p < 0.001). CONCLUSIONS: Compared to the worst outcomes for EQ-5D, the best outcomes were associated with patients with arm pain-only complaints. For mJOA, lower BMI and arm pain-only complaints portended the best outcomes. For NDI, those with the best outcomes had shorter symptom durations, higher preoperative neck pain scores, and less often underwent posterior spinal fusions. Given the positive impact of shorter symptom duration on outcomes, these data suggest that early surgery may be beneficial for patients with CSM.

Does the number of social factors affect long-term patient-reported outcomes and satisfaction in those with cervical myelopathy? A QOD study.

OBJECTIVE: It is not clear whether there is an additive effect of social factors in keeping patients with cervical spondylotic myelopathy (CSM) from achieving both a minimum clinically important difference (MCID) in outcomes and satisfaction after surgery. The aim of this study was to explore the effect of multiple social factors on postoperative outcomes and satisfaction. METHODS: This was a multiinstitutional, retrospective study of the prospective Quality Outcomes Database (QOD) CSM cohort, which included patients aged 18 years or older who were diagnosed with primary CSM and underwent operative management. Social factors included race (White vs non-White), education (high school or below vs above), employment (employed vs not), and insurance (private vs nonprivate). Patients were considered to have improved from surgery if the following criteria were met: 1) they reported a score of 1 or 2 on the North American Spine Society index, and 2) they met the MCID in patient-reported outcomes (i.e., visual analog scale [VAS] neck and arm pain, Neck Disability Index [NDI], and EuroQol-5D [EQ-5D]). RESULTS: Of the 1141 patients included in the study, 205 (18.0%) had 0, 347 (30.4%) had 1, 334 (29.3%) had 2, and 255 (22.3%) had 3 social factors. The 24-month follow-up rate was > 80% for all patient-reported outcomes. After adjusting for all relevant covariates (p < 0.02), patients with 1 or more social factors were less likely to improve from surgery in all measured outcomes including VAS neck pain (OR 0.90, 95% CI 0.83-0.99) and arm pain (OR 0.88, 95% CI 0.80-0.96); NDI (OR 0.90, 95% CI 0.83-0.98); and EQ-5D (OR 0.90, 95% CI 0.83-0.97) (all p < 0.05) compared to those without any social factors. Patients with 2 social factors (outcomes: neck pain OR 0.86, arm pain OR 0.81, NDI OR 0.84, EQ-5D OR 0.81; all p < 0.05) or 3 social factors (outcomes: neck pain OR 0.84, arm pain OR 0.84, NDI OR 0.84, EQ-5D OR 0.84; all p < 0.05) were more likely to fare worse in all outcomes compared to those with only 1 social factor. CONCLUSIONS: Compared to those without any social factors, patients who had at least 1 social factor were less likely to achieve MCID and feel satisfied after surgery. The effect of social factors is additive in that patients with a higher number of factors are less likely to improve compared to those with only 1 social factor.

What factors influence surgical decision-making in anterior versus posterior surgery for cervical myelopathy? A QOD analysis.

OBJECTIVE: The aim of this study was to explore the preoperative patient characteristics that affect surgical decision-making when selecting an anterior or posterior operative approach in patients diagnosed with cervical spondylotic myelopathy (CSM). METHODS: This was a multi-institutional, retrospective study of the prospective Quality Outcomes Database (QOD) Cervical Spondylotic Myelopathy module. Patients aged 18 years or older diagnosed with primary CSM who underwent multilevel (≥ 2-level) elective surgery were included. Demographics and baseline clinical characteristics were collected. RESULTS: Of the 841 patients with CSM in the database, 492 (58.5%) underwent multilevel anterior surgery and 349 (41.5%) underwent multilevel posterior surgery. Surgeons more often performed a posterior surgical approach in older patients (mean 64.8 ± 10.6 vs 58.5 ± 11.1 years, p < 0.001) and those with a higher American Society of Anesthesiologists class (class III or IV: 52.4% vs 46.3%, p = 0.003), a higher rate of motor deficit (67.0% vs 58.7%, p = 0.014), worse myelopathy (mean modified Japanese Orthopaedic Association score 11.4 ± 3.1 vs 12.4 ± 2.6, p < 0.001), and more levels treated (4.3 ± 1.3 vs 2.4 ± 0.6, p < 0.001). On the other hand, surgeons more frequently performed an anterior surgical approach when patients were employed (47.2% vs 23.2%, p < 0.001) and had intervertebral disc herniation as an underlying pathology (30.7% vs 9.2%, p < 0.001). CONCLUSIONS: The selection of approach for patients with CSM depends on patient demographics and symptomology. Posterior surgery was performed in patients who were older and had worse systemic disease, increased myelopathy, and greater levels of stenosis. Anterior surgery was more often performed in patients who were employed and had intervertebral disc herniation.

Cervical laminoplasty versus laminectomy and posterior cervical fusion for cervical myelopathy: propensity-matched analysis of 24-month outcomes from the Quality Outcomes Database.

OBJECTIVE: Compared with laminectomy with posterior cervical fusion (PCF), cervical laminoplasty (CL) may result in different outcomes for those operated on for cervical spondylotic myelopathy (CSM). The aim of this study was to compare 24-month patient-reported outcomes (PROs) for laminoplasty versus PCF by using the Quality Outcomes Database (QOD) CSM data set. METHODS: This was a retrospective study using an augmented data set from the prospectively collected QOD Registry Cervical Module. Patients undergoing laminoplasty or PCF for CSM were included. Using the nearest-neighbor method, the authors performed 1:1 propensity matching based on age, operated levels, and baseline modified Japanese Orthopaedic Association (mJOA) and visual analog scale (VAS) neck pain scores. The 24-month PROs, i.e., mJOA, Neck Disability Index (NDI), VAS neck pain, VAS arm pain, EQ-5D, EQ-VAS, and North American Spine Society (NASS) satisfaction scores, were compared. Only cases in the subaxial cervical region were included; those that crossed the cervicothoracic junction were excluded. RESULTS: From the 1141 patients included in the QOD CSM data set who underwent anterior or posterior surgery for cervical myelopathy, 946 (82.9%) had 24 months of follow-up. Of these, 43 patients who underwent laminoplasty and 191 who underwent PCF met the inclusion criteria. After matching, the groups were similar for baseline characteristics, including operative levels (CL group: 4.0 ± 0.9 vs PCF group: 4.2 ± 1.1, p = 0.337) and baseline PROs (p > 0.05), except for a higher percentage involved in activities outside the home in the CL group (95.3% vs 81.4%, p = 0.044). The 24-month follow-up for the matched cohorts was similar (CL group: 88.4% vs PCF group: 83.7%, p = 0.534). Patients undergoing laminoplasty had significantly lower estimated blood loss (99.3 ± 91.7 mL vs 186.7 ± 142.7 mL, p = 0.003), decreased length of stay (3.0 ± 1.6 days vs 4.5 ± 3.3 days, p = 0.012), and a higher rate of routine discharge (88.4% vs 62.8%, p = 0.006). The CL cohort also demonstrated a higher rate of return to activities (47.2% vs 21.2%, p = 0.023) after 3 months. Laminoplasty was associated with a larger improvement in 24-month NDI score (-19.6 ± 18.9 vs -9.1 ± 21.9, p = 0.031). Otherwise, there were no 3- or 24-month differences in mJOA, mean NDI, VAS neck pain, VAS arm pain, EQ-5D, EQ-VAS, and distribution of NASS satisfaction scores (p > 0.05) between the cohorts. CONCLUSIONS: Compared with PCF, laminoplasty was associated with decreased blood loss, decreased length of hospitalization, and higher rates of home discharge. At 3 months, laminoplasty was associated with a higher rate of return to baseline activities. At 24 months, laminoplasty was associated with greater improvements in neck disability. Otherwise, laminoplasty and PCF shared similar outcomes for functional status, pain, quality of life, and satisfaction. Laminoplasty and PCF achieved similar neck pain scores, suggesting that moderate preoperative neck pain may not necessarily be a contraindication for laminoplasty.

Three-level ACDF versus 3-level laminectomy and fusion: are there differences in outcomes? An analysis of the Quality Outcomes Database cervical spondylotic myelopathy cohort.

OBJECTIVE: The authors sought to compare 3-level anterior with posterior fusion surgical procedures for the treatment of multilevel cervical spondylotic myelopathy (CSM). METHODS: The authors analyzed prospective data from the 14 highest enrolling sites of the Quality Outcomes Database CSM module. They compared 3-level anterior cervical discectomy and fusion (ACDF) and posterior cervical laminectomy and fusion (PCF) surgical procedures, excluding surgical procedures crossing the cervicothoracic junction. Rates of reaching the minimal clinically important difference (MCID) in patient-reported outcomes (PROs) were compared at 24 months postoperatively. Multivariable analyses adjusted for potential confounders elucidated in univariable analysis. RESULTS: Overall, 199 patients met the inclusion criteria: 123 ACDF (61.8%) and 76 PCF (38.2%) patients. The 24-month follow-up rates were similar (ACDF 90.2% vs PCF 92.1%, p = 0.67). Preoperatively, ACDF patients were younger (60.8 ± 10.2 vs 65.0 ± 10.3 years, p < 0.01), and greater proportions were privately insured (56.1% vs 36.8%, p = 0.02), actively employed (39.8% vs 22.8%, p = 0.04), and independently ambulatory (14.6% vs 31.6%, p < 0.01). Otherwise, the cohorts had equivalent baseline modified Japanese Orthopaedic Association (mJOA), Neck Disability Index (NDI), numeric rating scale (NRS)-arm pain, NRS-neck pain, and EQ-5D scores (p > 0.05). ACDF patients had reduced hospitalization length (1.6 vs 3.9 days, p < 0.01) and a greater proportion had nonroutine discharge (7.3% vs 22.8%, p < 0.01), but they had a higher rate of postoperative dysphagia (13.5% vs 3.5%, p = 0.049). Compared with baseline values, both groups demonstrated improvements in all outcomes at 24 months (p < 0.05). In multivariable analyses, after controlling for age, insurance payor, employment status, ambulation status, and other potential clinically relevant confounders, ACDF was associated with a greater proportion of patients with maximum satisfaction on the North American Spine Society Patient Satisfaction Index (NASS) (NASS score of 1) at 24 months (69.4% vs 53.7%, OR 2.44, 95% CI 1.17-5.09, adjusted p = 0.02). Otherwise, the cohorts shared similar 24-month outcomes in terms of reaching the MCID for mJOA, NDI, NRS-arm pain, NRS-neck pain, and EQ-5D score (adjusted p > 0.05). There were no differences in the 3-month readmission (ACDF 4.1% vs PCF 3.9%, p = 0.97) and 24-month reoperation (ACDF 13.5% vs PCF 18.6%, p = 0.36) rates. CONCLUSIONS: In a cohort limited to 3-level fusion surgical procedures, ACDF was associated with reduced blood loss, shorter hospitalization length, and higher routine home discharge rates; however, PCF resulted in lower rates of postoperative dysphagia. The procedures yielded comparably significant improvements in functional status (mJOA score), neck and arm pain, neck pain-related disability, and quality of life at 3, 12, and 24 months. ACDF patients had significantly higher odds of maximum satisfaction (NASS score 1). Given comparable outcomes, patients should be counseled on each approach's complication profile to aid in surgical decision-making.

Which supervised machine learning algorithm can best predict achievement of minimum clinically important difference in neck pain after surgery in patients with cervical myelopathy? A QOD study.

OBJECTIVE: The purpose of this study was to evaluate the performance of different supervised machine learning algorithms to predict achievement of minimum clinically important difference (MCID) in neck pain after surgery in patients with cervical spondylotic myelopathy (CSM). METHODS: This was a retrospective analysis of the prospective Quality Outcomes Database CSM cohort. The data set was divided into an 80% training and a 20% test set. Various supervised learning algorithms (including logistic regression, support vector machine, decision tree, random forest, extra trees, gaussian naïve Bayes, k-nearest neighbors, multilayer perceptron, and extreme gradient boosted trees) were evaluated on their performance to predict achievement of MCID in neck pain at 3 and 24 months after surgery, given a set of predicting baseline features. Model performance was assessed with accuracy, F1 score, area under the receiver operating characteristic curve, precision, recall/sensitivity, and specificity. RESULTS: In total, 535 patients (46.9%) achieved MCID for neck pain at 3 months and 569 patients (49.9%) achieved it at 24 months. In each follow-up cohort, 501 patients (93.6%) were satisfied at 3 months after surgery and 569 patients (100%) were satisfied at 24 months after surgery. Of the supervised machine learning algorithms tested, logistic regression demonstrated the best accuracy (3 months: 0.76 ± 0.031, 24 months: 0.773 ± 0.044), followed by F1 score (3 months: 0.759 ± 0.019, 24 months: 0.777 ± 0.039) and area under the receiver operating characteristic curve (3 months: 0.762 ± 0.027, 24 months: 0.773 ± 0.043) at predicting achievement of MCID for neck pain at both follow-up time points, with fair performance. The best precision was also demonstrated by logistic regression at 3 (0.724 ± 0.058) and 24 (0.780 ± 0.097) months. The best recall/sensitivity was demonstrated by multilayer perceptron at 3 months (0.841 ± 0.094) and by extra trees at 24 months (0.817 ± 0.115). Highest specificity was shown by support vector machine at 3 months (0.952 ± 0.013) and by logistic regression at 24 months (0.747 ± 0.18). CONCLUSIONS: Appropriate selection of models for studies should be based on the strengths of each model and the aims of the studies. For maximally predicting true achievement of MCID in neck pain, of all the predictions in this balanced data set the appropriate metric for the authors' study was precision. For both short- and long-term follow-ups, logistic regression demonstrated the highest precision of all models tested. Logistic regression performed consistently the best of all models tested and remains a powerful model for clinical classification tasks.

Do comorbid self-reported depression and anxiety influence outcomes following surgery for cervical spondylotic myelopathy?

OBJECTIVE: Depression and anxiety are associated with inferior outcomes following spine surgery. In this study, the authors examined whether patients with cervical spondylotic myelopathy (CSM) who have both self-reported depression (SRD) and self-reported anxiety (SRA) have worse postoperative patient-reported outcomes (PROs) compared with patients who have only one or none of these comorbidities. METHODS: This study is a retrospective analysis of prospectively collected data from the Quality Outcomes Database CSM cohort. Comparisons were made among patients who reported the following: 1) either SRD or SRA, 2) both SRD and SRA, or 3) neither comorbidity at baseline. PROs at 3, 12, and 24 months (scores for the visual analog scale [VAS] for neck pain and arm pain, Neck Disability Index [NDI], modified Japanese Orthopaedic Association [mJOA] scale, EQ-5D, EuroQol VAS [EQ-VAS], and North American Spine Society [NASS] patient satisfaction index) and achievement of respective PRO minimal clinically important differences (MCIDs) were compared. RESULTS: Of the 1141 included patients, 199 (17.4%) had either SRD or SRA alone, 132 (11.6%) had both SRD and SRA, and 810 (71.0%) had neither. Preoperatively, patients with either SRD or SRA alone had worse scores for VAS neck pain (5.6 ± 3.1 vs 5.1 ± 3.3, p = 0.03), NDI (41.0 ± 19.3 vs 36.8 ± 20.8, p = 0.007), EQ-VAS (57.0 ± 21.0 vs 60.7 ± 21.7, p = 0.03), and EQ-5D (0.53 ± 0.23 vs 0.58 ± 0.21, p = 0.008) than patients without such disorders. Postoperatively, in multivariable adjusted analyses, baseline SRD or SRA alone was associated with inferior improvement in the VAS neck pain score and a lower rate of achieving the MCID for VAS neck pain score at 3 and 12 months, but not at 24 months. At 24 months, patients with SRD or SRA alone experienced less change in EQ-5D scores and were less likely to meet the MCID for EQ-5D than patients without SRD or SRA. Furthermore, patient self-reporting of both psychological comorbidities did not impact PROs at all measured time points compared with self-reporting of only one psychological comorbidity alone. Each cohort (SRD or SRA alone, both SRD and SRA, and neither SRD nor SRA) experienced significant improvements in mean PROs at all measured time points compared with baseline (p < 0.05). CONCLUSIONS: Approximately 12% of patients who underwent surgery for CSM presented with both SRD and SRA, and 29% presented with at least one symptom. The presence of either SRD or SRA was independently associated with inferior scores for 3- and 12-month neck pain following surgery, but this difference was not significant at 24 months. However, at long-term follow-up, patients with SRD or SRA experienced lower quality of life than patients without SRD or SRA. The comorbid presence of both depression and anxiety was not associated with worse patient outcomes than either diagnosis alone.

Sleep Disturbances in Cervical Spondylotic Myelopathy: Prevalence and Postoperative Outcomes-an Analysis From the Quality Outcomes Database.

STUDY DESIGN: Prospective observational study, level of evidence 1 for prognostic investigations. OBJECTIVES: To evaluate the prevalence of sleep impairment and predictors of improved sleep quality 24 months postoperatively in cervical spondylotic myelopathy (CSM) using the quality outcomes database. SUMMARY OF BACKGROUND DATA: Sleep disturbances are a common yet understudied symptom in CSM. MATERIALS AND METHODS: The quality outcomes database was queried for patients with CSM, and sleep quality was assessed through the neck disability index sleep component at baseline and 24 months postoperatively. Multivariable logistic regressions were performed to identify risk factors of failure to improve sleep impairment and symptoms causing lingering sleep dysfunction 24 months after surgery. RESULTS: Among 1135 patients with CSM, 904 (79.5%) had some degree of sleep dysfunction at baseline. At 24 months postoperatively, 72.8% of the patients with baseline sleep symptoms experienced improvement, with 42.5% reporting complete resolution. Patients who did not improve were more like to be smokers [adjusted odds ratio (aOR): 1.85], have osteoarthritis (aOR: 1.72), report baseline radicular paresthesia (aOR: 1.51), and have neck pain of ≥4/10 on a numeric rating scale. Patients with improved sleep noted higher satisfaction with surgery (88.8% vs 72.9%, aOR: 1.66) independent of improvement in other functional areas. In a multivariable analysis including pain scores and several myelopathy-related symptoms, lingering sleep dysfunction at 24 months was associated with neck pain (aOR: 1.47) and upper (aOR: 1.45) and lower (aOR: 1.52) extremity paresthesias. CONCLUSION: The majority of patients presenting with CSM have associated sleep disturbances. Most patients experience sustained improvement after surgery, with almost half reporting complete resolution. Smoking, osteoarthritis, radicular paresthesia, and neck pain ≥4/10 numeric rating scale score are baseline risk factors of failure to improve sleep dysfunction. Improvement in sleep symptoms is a major driver of patient-reported satisfaction. Incomplete resolution of sleep impairment is likely due to neck pain and extremity paresthesia.

Management of Anticoagulation/Antiplatelet Medication and Venous Thromboembolism Prophylaxis in Elective Spine Surgery: Concise Clinical Recommendations Based on a Modified Delphi Process.

STUDY DESIGN: Delphi method. OBJECTIVE: To gain consensus on the following questions: (1) When should anticoagulation/antiplatelet (AC/AP) medication be stopped before elective spine surgery?; (2) When should AC/AP medication be restarted after elective spine surgery?; (3) When, how, and in whom should venous thromboembolism (VTE) chemoprophylaxis be started after elective spinal surgery? SUMMARY OF BACKGROUND DATA: VTE can lead to significant morbidity after adult spine surgery, yet postoperative VTE prophylaxis practices vary considerably. The management of preoperative AC/AP medication is similarly heterogeneous. MATERIALS AND METHODS: Delphi method of consensus development consisting of three rounds (January 26, 2021, to June 21, 2021). RESULTS: Twenty-one spine surgeons were invited, and 20 surgeons completed all rounds of questioning. Consensus (>70% agreement) was achieved in 26/27 items. Group consensus stated that preoperative Direct Oral Anticoagulants should be stopped two days before surgery, warfarin stopped five days before surgery, and all remaining AC/AP medication and aspirin should be stopped seven days before surgery. For restarting AC/AP medication postoperatively, consensus was achieved for low-risk/medium-risk/high-risk patients in 5/5 risk factors (VTE history/cardiac/ambulation status/anterior approach/operation). The low/medium/high thresholds were POD7/POD5/POD2, respectively. For VTE chemoprophylaxis, consensus was achieved for low-risk/medium-risk/high-risk patients in 12/13 risk factors (age/BMI/VTE history/cardiac/cancer/hormone therapy/operation/anterior approach/staged separate days/staged same days/operative time/transfusion). The one area that did not gain consensus was same-day staged surgery. The low-threshold/medium-threshold/high-threshold ranges were postoperative day 5 (POD5) or none/POD3-4/POD1-2, respectively. Additional VTE chemoprophylaxis considerations that gained consensus were POD1 defined as the morning after surgery regardless of operating finishing time, enoxaparin as the medication of choice, and standardized, rather than weight-based, dose given once per day. CONCLUSIONS: In the first known Delphi study to address anticoagulation/antiplatelet recommendations for elective spine surgery (preoperatively and postoperatively); our Delphi consensus recommendations from 20 spine surgeons achieved consensus on 26/27 items. These results will potentially help standardize the management of preoperative AC/AP medication and VTE chemoprophylaxis after adult elective spine surgery.

Cervical spondylotic myelopathy with severe axial neck pain: is anterior or posterior approach better?

OBJECTIVE: The aim of this study was to determine whether multilevel anterior cervical discectomy and fusion (ACDF) or posterior cervical laminectomy and fusion (PCLF) is superior for patients with cervical spondylotic myelopathy (CSM) and high preoperative neck pain. METHODS: This was a retrospective study of prospectively collected data using the Quality Outcomes Database (QOD) CSM module. Patients who received a subaxial fusion of 3 or 4 segments and had a visual analog scale (VAS) neck pain score of 7 or greater at baseline were included. The 3-, 12-, and 24-month outcomes were compared for patients undergoing ACDF with those undergoing PCLF. RESULTS: Overall, 1141 patients with CSM were included in the database. Of these, 495 (43.4%) presented with severe neck pain (VAS score > 6). After applying inclusion and exclusion criteria, we compared 65 patients (54.6%) undergoing 3- and 4-level ACDF and 54 patients (45.4%) undergoing 3- and 4-level PCLF. Patients undergoing ACDF had worse Neck Disability Index scores at baseline (52.5 ± 15.9 vs 45.9 ± 16.8, p = 0.03) but similar neck pain (p > 0.05). Otherwise, the groups were well matched for the remaining baseline patient-reported outcomes. The rates of 24-month follow-up for ACDF and PCLF were similar (86.2% and 83.3%, respectively). At the 24-month follow-up, both groups demonstrated mean improvements in all outcomes, including neck pain (p < 0.05). In multivariable analyses, there was no significant difference in the degree of neck pain change, rate of neck pain improvement, rate of pain-free achievement, and rate of reaching minimal clinically important difference (MCID) in neck pain between the two groups (adjusted p > 0.05). However, ACDF was associated with a higher 24-month modified Japanese Orthopaedic Association scale (mJOA) score (ß = 1.5 [95% CI 0.5-2.6], adjusted p = 0.01), higher EQ-5D score (ß = 0.1 [95% CI 0.01-0.2], adjusted p = 0.04), and higher likelihood for return to baseline activities (OR 1.2 [95% CI 1.1-1.4], adjusted p = 0.002). CONCLUSIONS: Severe neck pain is prevalent among patients undergoing surgery for CSM, affecting more than 40% of patients. Both ACDF and PCLF achieved comparable postoperative neck pain improvement 3, 12, and 24 months following 3- or 4-segment surgery for patients with CSM and severe neck pain. However, multilevel ACDF was associated with superior functional status, quality of life, and return to baseline activities at 24 months in multivariable adjusted analyses.

Correlation of the Modified Japanese Orthopedic Association With Functional and Quality-of-Life Outcomes After Surgery for Degenerative Cervical Myelopathy: A Quality Outcomes Database Study.

BACKGROUND: The modified Japanese Orthopedic Association (mJOA) score is a widely used and validated metric for assessing severity of myelopathy. Its relationship to functional and quality-of-life outcomes after surgery has not been fully described. OBJECTIVE: To quantify the association of the mJOA with the Neck Disability Index (NDI) and EuroQol-5 Dimension (EQ-5D) after surgery for degenerative cervical myelopathy. METHODS: The cervical module of the prospectively enrolled Quality Outcomes Database was queried retrospectively for adult patients who underwent single-stage degenerative cervical myelopathy surgery. The mJOA score, NDI, and EQ-5D were assessed preoperatively and 3 and 12 months postoperatively. Improvement in mJOA was used as the independent variable in univariate and multivariable linear and logistic regression models. RESULTS: Across 14 centers, 1121 patients were identified, mean age 60.6 ± 11.8 years, and 52.5% male. Anterior-only operations were performed in 772 patients (68.9%). By univariate linear regression, improvements in mJOA were associated with improvements in NDI and EQ-5D at 3 and 12 months postoperatively (all P < .0001) and with improvements in the 10 NDI items individually. These findings were similar in multivariable regression incorporating potential confounders. The Pearson correlation coefficients for changes in mJOA with changes in NDI were -0.31 and -0.38 at 3 and 12 months postoperatively. The Pearson correlation coefficients for changes in mJOA with changes in EQ-5D were 0.29 and 0.34 at 3 and 12 months. CONCLUSION: Improvements in mJOA correlated weakly with improvements in NDI and EQ-5D, suggesting that changes in mJOA may not be a suitable proxy for functional and quality-of-life outcomes.

Primary Spinal Cord Astrocytomas: Two-Center Clinical Experience of Low- and High-Grade Lesions.

OBJECTIVE: Primary spinal cord astrocytomas are rare, fatal, and poorly studied. METHODS: This study included a 2-center, retrospective analysis of primary spinal cord astrocytoma patients from 1997 to 2020. Patients with drop metastases or without at least one follow-up were excluded. RESULTS: Seven World Health Organization grade I, 6 grade II, 7 grade III, and 4 grade IV astrocytoma patients were included. Older patients had higher grades (median 20 years in grade I vs. 36.5 in grade IV). The median follow-up was 15 months. Thirteen patients were discharged to rehabilitation. Eight patients demonstrated radiographic progression. Adjuvant therapy was utilized more in higher grades (5 of 13 grades III vs. all 11 grades IIIIV). Six patients died (1 death in grades III vs. 5 in grades IIIIV). Ten patients had worsened symptoms at the last follow-up. The median progression-free survival in grade I, II, III, and IV tumors was 116, 36, 8, and 8.5 months, respectively. The median overall survival in grade I, II, III, and IV tumors was 142, 69, 19, and 12 months, respectively. Thrombotic complications occurred in 2 patients, one with isocitrate dehydrogenasewild type glioblastoma. CONCLUSIONS: Outcomes worsen with higher grades and lead to difficult postoperative periods. Clinicians should be vigilant for thromboembolic complications. Further research is needed to understand these rare tumors.

A multicenter study of the 5-year trends in robot-assisted spine surgery outcomes and complications.

Background: Although a growing amount of literature that suggests robots are safe and can achieve comparable outcomes to conventional techniques, much of this literature is limited by small sample sizes and single-surgeon or single center series. Furthermore, it is unclear what the impact of robotic technology has made on operative and clinical outcomes over time. This is the first and largest multicenter study to examine the trends in outcomes and complications after robot-assisted spine surgery over a 5-year period. Methods: Adult (≥18 years old) patients who underwent spine surgery with robot-assistance between 2015 and 2019 at four unique spine centers. The robotic systems used included the Mazor Renaissance, Mazor X, and Mazor Stealth Edition. Patients with incomplete data were excluded from this study. The minimum follow-up was 90 days. Results: A total of 722 adult patients were included (117 Renaissance, 477 X, 128 Stealth). Most patient and operative factors (e.g., sex, tobacco status, total instrumented levels, and pelvic fixation,) were similar across the years. Mean ± standard deviation Charlson comorbidity index (CCI) was 1.5±1.5. The most commonly reported diagnoses included high grade spondylolisthesis (40.6%), degenerative disc disease (18.4%), and degenerative scoliosis (17.6%). Mean (standard deviation) number of instrumented levels was 3.8±3.4. From 2015 to 2019, average robot time per screw improved from 7.2 to 5.5 minutes (P=0.004, R2=0.649). Average fluoroscopy time per screw improved from 15.2 to 9.4 seconds (P=0.002). Rates of both intraoperative screw exchange for misplaced screw (2015-2016: 2.7%, 2019: 0.8%, P=0.0115, R2=0.1316) and robot abandonment (2015-2016: 7.1%, 2019: 1.1%, P=0.011, R2=0.215) improved significantly over time. The incidence of other intraoperative complications (e.g., dural tear, loss of motor/sensory function, blood transfusion) remained consistently low, but similar throughout the years. The length of stay (LOS) decreased by nearly 1 day from 2015 to 2019 (P=0.007, R2=0.779). 90-day reoperation rates did not change significantly. Conclusions: At four institutions among seven surgeons, we demonstrate robot screw accuracy, reliability, operative efficiency, and radiation exposure improved significantly from 2015 to 2019. 90-day complication rates remained low and LOS decreased significantly with time. These findings further validate continued usage of robot-assisted spine surgery and the path toward improved value-based care.

High-impact chronic pain transition in surgical recipients with cervical spondylotic myelopathy.

OBJECTIVE: High-impact chronic pain (HICP) is a recently proposed metric that indicates the presence of a severe and troubling pain-related condition. Surgery for cervical spondylotic myelopathy (CSM) is designed to halt disease transition independent of chronic pain status. To date, the prevalence of HICP in individuals with CSM and their HICP transition from presurgery is unexplored. The authors sought to define HICP prevalence, transition, and outcomes in patients with CSM who underwent surgery and identify predictors of these HICP transition groups. METHODS: CSM surgical recipients were categorized as HICP at presurgery and 3 months if they exhibited pain that lasted 6-12 months or longer with at least one major activity restriction. HICP transition groups were categorized and evaluated for outcomes. Multivariate multinomial modeling was used to predict HICP transition categorization. RESULTS: A majority (56.1%) of individuals exhibited HICP preoperatively; this value declined to 15.9% at 3 months (71.6% reduction). The presence of HICP was also reflective of other self-reported outcomes at 3 and 12 months, as most demonstrated notable improvement. Higher severity in all categories of self-reported outcomes was related to a continued HICP condition at 3 months. Both social and biological factors predicted HICP translation, with social factors being predominant in transitioning to HICP (from none preoperatively). CONCLUSIONS: Many individuals who received CSM surgery changed HICP status at 3 months. In a surgical population where decisions are based on disease progression, most of the changed status went from HICP preoperatively to none at 3 months. Both social and biological risk factors predicted HICP transition assignment.

Social risk factors predicting outcomes of cervical myelopathy surgery.

OBJECTIVE: Combinations of certain social risk factors of race, sex, education, socioeconomic status (SES), insurance, education, employment, and one's housing situation have been associated with poorer pain and disability outcomes after lumbar spine surgery. To date, an exploration of such factors in patients with cervical spine surgery has not been conducted. The objective of the current work was to 1) define the social risk phenotypes of individuals who have undergone cervical spine surgery for myelopathy and 2) analyze their predictive capacity toward disability, pain, quality of life, and patient satisfaction-based outcomes. METHODS: The Cervical Myelopathy Quality Outcomes Database was queried for the period from January 2016 to December 2018. Race/ethnicity, educational attainment, SES, insurance payer, and employment status were modeled into unique social phenotypes using latent class analyses. Proportions of social groups were analyzed for demonstrating a minimal clinically important difference (MCID) of 30% from baseline for disability, neck and arm pain, quality of life, and patient satisfaction at the 3-month and 1-year follow-ups. RESULTS: A total of 730 individuals who had undergone cervical myelopathy surgery were included in the final cohort. Latent class analysis identified 2 subgroups: 1) high risk (non-White race and ethnicity, lower educational attainment, not working, poor insurance, and predominantly lower SES), n = 268, 36.7% (class 1); and 2) low risk (White, employed with good insurance, and higher education and SES), n = 462, 63.3% (class 2). For both 3-month and 1-year outcomes, the high-risk group (class 1) had decreased odds (all p < 0.05) of attaining an MCID score in disability, neck/arm pain, and health-related quality of life. Being in the low-risk group (class 2) resulted in an increased odds of attaining an MCID score in disability, neck/arm pain, and health-related quality of life. Neither group had increased or decreased odds of being satisfied with surgery. CONCLUSIONS: Although 2 groups underwent similar surgical approaches, the social phenotype involving non-White race/ethnicity, poor insurance, lower SES, and poor employment did not meet MCIDs for a variety of outcome measures. This finding should prompt surgeons to proactively incorporate socially conscience care pathways within healthcare systems, as well as to optimize community-based resources to improve outcomes and personalize care for populations at social risk.

Association of ≥ 12 months of delayed surgical treatment for cervical myelopathy with worsened postoperative outcomes: a multicenter analysis of the Quality Outcomes Database.

OBJECTIVE: Degenerative cervical myelopathy (DCM) results in significant morbidity. The duration of symptoms prior to surgical intervention may be associated with postoperative surgical outcomes and functional recovery. The authors' objective was to investigate whether delayed surgical treatment for DCM is associated with worsened postoperative outcomes. METHODS: Data from 1036 patients across 14 surgical centers in the Quality Outcomes Database were analyzed. Baseline demographic characteristics and findings of preoperative and postoperative symptom evaluations, including duration of symptoms, were assessed. Postoperative functional outcomes were measured using the Neck Disability Index (NDI) and modified Japanese Orthopaedic Association (mJOA) scale. Symptom duration was classified as either less than 12 months or 12 months or greater. Univariable and multivariable regression were used to evaluate for the associations between symptom duration and postoperative outcomes. RESULTS: In this study, 513 patients (49.5%) presented with symptom duration < 12 months, and 523 (50.5%) had symptoms for 12 months or longer. Patients with longer symptom duration had higher BMI and higher prevalence of anxiety and diabetes (all p < 0.05). Symptom duration ≥ 12 months was associated with higher average baseline NDI score (41 vs 36, p < 0.01). However, improvements in NDI scores from baseline were not significantly different between groups at 3 months (p = 0.77) or 12 months (p = 0.51). Likewise, the authors found no significant differences between groups in changes in mJOA scores from baseline to 3 months or 12 months (both p > 0.05). CONCLUSIONS: Surgical intervention resulted in improved mJOA and NDI scores at 3 months, and this improvement was sustained in both patients with short and longer initial symptom duration. Patients with DCM can still undergo successful surgical management despite delayed presentation.

What Is the Comparison in Robot Time per Screw, Radiation Exposure, Robot Abandonment, Screw Accuracy, and Clinical Outcomes Between Percutaneous and Open Robot-Assisted Short Lumbar Fusion?: A Multicenter, Propensity-Matched Analysis of 310 Patients.

STUDY DESIGN: Multicenter cohort. OBJECTIVE: To compare the robot time/screw, radiation exposure, robot abandonment, screw accuracy, and 90-day outcomes between robot-assisted percutaneous and robot-assisted open approach for short lumbar fusion (1- and 2-level). SUMMARY OF BACKGROUND DATA: There is conflicting literature on the superiority of robot-assisted minimally invasive spine surgery to open techniques. A large, multicenter study is needed to further elucidate the outcomes and complications between these two approaches. METHODS: We included adult patients (≥18 yrs old) who underwent robot-assisted short lumbar fusion surgery from 2015 to 2019 at four independent institutions. A propensity score matching algorithm was employed to control for the potential selection bias between percutaneous and open surgery. The minimum follow-up was 90 days after the index surgery. RESULTS: After propensity score matching, 310 patients remained. The mean (standard deviation) Charlson comorbidity index was 1.6 (1.5) and 53% of patients were female. The most common diagnoses included high-grade spondylolisthesis (grade >2) (48%), degenerative disc disease (22%), and spinal stenosis (25%), and the mean number of instrumented levels was 1.5(0.5). The operative time was longer in the open (198 min) versus the percutaneous group (167 min, P value = 0.007). However, the robot time/screw was similar between cohorts (P value > 0.05). The fluoroscopy time/ screw for percutaneous (14.4 s) was longer than the open group (10.1 s, P value = 0.021). The rates for screw exchange and robot abandonment were similar between groups (P value > 0.05). The estimated blood loss (open: 146 mL vs. percutaneous: 61.3 mL, P value < 0.001) and transfusion rate (open: 3.9% vs. percutaneous: 0%, P value = 0.013) were greater for the open group. The 90-day complication rate and mean length of stay were not different between cohorts (P value > 0.05). CONCLUSION: Percutaneous robot-assisted spine surgery may increase radiation exposure, but can achieve a shorter operative time and lower risk for intraoperative blood loss for short-lumbar fusion. Percutaneous approaches do not appear to have an advantage for other short-term postoperative outcomes. Future multicenter studies on longer fusion surgeries and the inclusion of patient-reported outcomes are needed.Level of Evidence: 3.

Ninety-day complication, revision, and readmission rates for current-generation robot-assisted thoracolumbar spinal fusion surgery: results of a multicenter case series.

OBJECTIVE: Robotics is a major area for research and development in spine surgery. The high accuracy of robot-assisted placement of thoracolumbar pedicle screws is documented in the literature. The authors present the largest case series to date evaluating 90-day complication, revision, and readmission rates for robot-assisted spine surgery using the current generation of robotic guidance systems. METHODS: An analysis of a retrospective, multicenter database of open and minimally invasive thoracolumbar instrumented fusion surgeries using the Mazor X or Mazor X Stealth Edition robotic guidance systems was performed. Patients 18 years of age or older and undergoing primary or revision surgery for degenerative spinal conditions were included. Descriptive statistics were used to calculate rates of malpositioned screws requiring revision, as well as overall complication, revision, and readmission rates within 90 days. RESULTS: In total, 799 surgical cases (Mazor X: 48.81%; Mazor X Stealth Edition: 51.19%) were evaluated, involving robot-assisted placement of 4838 pedicle screws. The overall intraoperative complication rate was 3.13%. No intraoperative implant-related complications were encountered. Postoperatively, 129 patients suffered a total of 146 complications by 90 days, representing an incidence of 16.1%. The rate of an unrecognized malpositioned screw resulting in a new postoperative radiculopathy requiring revision surgery was 0.63% (5 cases). Medical and pain-related complications unrelated to hardware placement accounted for the bulk of postoperative complications within 90 days. The overall surgical revision rate at 90 days was 6.63% with 7 implant-related revisions, representing an implant-related revision rate of 0.88%. The 90-day readmission rate was 7.13% with 2 implant-related readmissions, representing an implant-related readmission rate of 0.25% of cases. CONCLUSIONS: The results of this multicenter case series and literature review suggest current-generation robotic guidance systems are associated with low rates of intraoperative and postoperative implant-related complications, revisions, and readmissions at 90 days. Future outcomes-based studies are necessary to evaluate complication, revision, and readmission rates compared to conventional surgery.

FGFR1-TACC1 fusion associated with malignant transformation in a primary spinal cord glioma: a case report.

Molecular mechanisms of malignant transformation in spinal cord gliomas are not well-understood. Our objective was to investigate genetic causes of malignant transformation in a primary spinal cord glioma. A 32-year-old female patient presented with bilateral lower extremity weakness and was diagnosed with a primary spinal cord glioma from T9 to T12, with a syrinx extending from the craniocervical junction to the conus. She underwent resection in 2006. Pathology showed an abundance of Rosenthal fibers, calcification and degenerative features consistent with a low-grade pilocytic astrocytoma. She presented in 2020 with tumor recurrence and underwent re-resection. Whole exome sequencing, DNA methylation profiling and immunohistochemistry were performed on her initial and recurrent tumor samples. Immunohistochemical profiling of her recurrent tumor showed pleomorphic cells with extensive necrosis consistent with a high-grade glioma. DNA methylation profiling showed that the initial tumor clustered with pilocytic astrocytomas, whereas the recurrent lesion clustered with anaplastic astrocytomas, confirming malignant transformation. Whole-exome sequencing showed interim acquisition of a rare fibroblast growth factor receptor-transforming acidic coiled-coil (FGFR1-TACC1) gene fusion. We report an FGFR1-TACC1 fusion associated with malignant transformation in a primary spinal cord glioma. Our study adds to growing reports of FGFR-TACC fusions, which are amenable to receptor tyrosine kinase inhibition.

MAZOR-X robotic-navigated percutaneous C2 screw placement for hangman's fracture: a case report.

Robotic-navigated screw placement has potential for higher precision and accuracy. Robotic assistance is well-described in the lumbar spine, however only few studies have evaluated its use in the cervical spine. Surgical treatment for hangman's fractures after nonunion typically involves C2-3 anterior fusion or posterior occipito-cervical fusion. However, occipito-cervical fusion involves loss of mobility in the cervical spine with associated morbidity. We have previously described a minimally invasive approach using percutaneous screw fixation with X-ray navigation. Robotic assistance is ideally suited for cervical fusion given smaller bony anatomy and adjacent critical structures. We describe a young healthy patient who presented with a hangman's fracture initially managed conservatively with immobilization. She presented with nonunion and persistent symptoms. Surgical options considered included anterior cervical discectomy and fusion, or posterior cervical fusion with or without extension to the occiput. These options would have involved some loss of flexion/extension and rotational motion with associated morbidity. We performed percutaneous screw fixation of the hangman's fracture using MAZOR-X robotic navigation and achieved good radiographic fracture reduction with accurate screw placement. To our knowledge this is the first case of a robotic-assisted percutaneous screw fixation for a hangman's fracture. Robotic-navigated screw placement can be used safely and accurately for cervical spine fractures.