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Knightly, John J.

https://orcid.org/0000-0003-0917-9265

A5088033349 | I67339987

Mayo Clinic

Atlantic Neurosurgical Specialists, Morristown, NJ

Citations 82

Comparing those Most Satisfied Versus Least Satisfied Following Surgery for Cervical Spondylotic Myelopathy

Spine | July 3, 2026 | Volume: 51 | Issue: 15 | Pages: 1093-1100

10.1097/brs.0000000000005402 | PMID 42398026

Study Design. Post hoc analysis of prospectively-collected data. Objective. To identify factors predicting the most (and least) satisfaction following surgery for cervical spondylotic myelopathy (CSM). Summary of Background Data. Patient satisfaction affects long-term outcomes after surgery but the preoperative factors that influence postoperative satisfaction have not been well studied in patients with CSM. Methods. We conducted a post hoc analysis of prospectively-collected data from the Quality Outcomes Database (QOD) CSM registry cohort. Baseline and surgical characteristics were compared for patients with CSM reporting the most [North American Spine Society Satisfaction Score (NASS) 1] and least (NASS 4) satisfaction 24 months postoperatively. A multivariable logistic regression model was constructed using backward stepwise elimination to determine significant predictors of most versus least satisfaction. Twenty-four-month patient-reported outcomes (PROs) were compared. Results. Overall, 1141 patients were prospectively enrolled with 948 (83.1%) reaching 24-month follow-up. Of these, 699 met prespecified inclusion criteria: 610 (87.3%) were most satisfied and 89 (12.7%) were least satisfied. Though there were mean improvements in all 24-month PROs for the most satisfied cohort ( P <0.001), there were no significant improvements in 24-month PROs for the least satisfied cohort ( P >0.05). Using multivariable logistic regression modeling, a preoperative symptom of upper extremity weakness (OR=2.5, P =0.003), subjective myelopathy (OR=2.0, P =0.04), absence of numbness complaints (OR=2.2, P =0.003), symptom duration under 12 months (OR=1.6, P =0.047), Caucasian race (OR=2.3, P =0.001), participation in activities outside of the home (OR=2.0, P =0.04), anterior approach (OR=2.3, P <0.001), and higher baseline quality of life (OR=4.0, P =0.01) were predictive of the most satisfaction. Conclusion. Compared with the least satisfied, those most satisfied following surgery for CSM more often had a preoperative symptom of arm weakness, subjective myelopathy, the absence of numbness complaints, symptom duration under 12 months, higher baseline quality of life, and participation in activities outside of the home. Compared with a posterior approach, an anterior approach was associated with the most satisfaction. Taken together, early surgical treatment--before myelopathic symptoms significantly impact one's quality of life--may be considered to optimize patient satisfaction following CSM surgery.
Using the Quality Outcomes Database to Identify Minimum Clinically Important Differences for Patients With Cervical Spondylotic Myelopathy

Neurosurgery | January 9, 2026 | Volume: 98 | Issue: 6 | Pages: 1347-1358

10.1227/neu.0000000000003902 | PMID 41511085

BACKGROUND AND OBJECTIVES: Minimum clinically important differences (MCIDs) for patient-reported outcome metrics (PROMs) in patients with cervical spondylotic myelopathy (CSM) lack consensus on the most appropriate calculation method. This retrospective study aimed to identify the optimal MCIDs for commonly used PROMs in CSM. METHODS: The CSM database from the Quality Outcomes Database SpineCORe Study Group was analyzed. Baseline, 3-month, and 24-month PROM values for Neck Disability Index (NDI), 5-dimension Euro-quality of life (EQ-5D) in quality-adjusted life years, modified Japanese Orthopaedic Association (mJOA) score, and neck/arm pain numeric rating scale (NRS) were collected. MCIDs were calculated for each PROM using previously validated techniques. MCID values were compared using the area under the curve (AUC) with the North American Spine Society satisfaction scale as an anchor. RESULTS: A total of 1141 patients with CSM undergoing surgery were included in this analysis. Improvement of ≥30% from baseline was the optimal MCID for NDI and neck/arm NRS. At 24 months, the optimal percentage cutoff MCID for these instruments resulted in AUCs of 0.76, 0.72, and 0.67, similar to the 30% improvement method, with AUCs of 0.73, 0.71, and 0.67, respectively. Numeric cutoffs (0.065 at 3 months; 0.149 at 24 months) were the superior MCIDs for EQ-5D. For mJOA score, a severity-adjusted MCID outperformed other methods, yielding an AUC of 0.67 at 24 months. MCIDs were achieved in 63% of patients for NDI, 59% for neck pain NRS, 61% for arm pain NRS, 52% for EQ-5D, and 59% for mJOA score at 24 months. CONCLUSION: Using the Quality Outcomes Database SpineCORe data set, we defined optimal MCIDs for key PROMs in CSM. A ≥30% improvement from baseline was optimal in NDI and arm/neck NRS. An absolute numeric cutoff was superior for EQ-5D (0.149 at the 24-month follow-up). A severity-adjusted MCID performed best for mJOA score. These redefined benchmarks better capture the treatment impact and guide care decisions for patients with CSM.
In Reply: Are There Differences in 2-Year Outcomes Between 2-Level Anterior Cervical Diskectomy and Fusion Versus Single-Level Anterior Cervical Corpectomy and Fusion to Treat Cervical Myelopathy? A Quality Outcomes Database Study

Neurosurgery | October 14, 2025 | Volume: 97 | Issue: 6 | Pages: e177-e178

10.1227/neu.0000000000003811 | PMID 41085387

Does back pain catastrophizing influence 60-month surgical outcomes for patients with degenerative lumbar spondylolisthesis? A Quality Outcomes Database study

Journal of Neurosurgery: Spine | September 12, 2025 | Volume: 43 | Issue: 5 | Pages: 529-539

10.3171/2025.5.spine25310 | PMID 40779803

OBJECTIVE Degenerative lumbar spondylolisthesis is a common cause of back and leg pain influenced by factors like instability, disc degeneration, facet arthropathy, and psychosocial phenotype. Patients’ experience of high-severity pain is complex, with significant implications for surgical planning. The goal of this study was to assess the impact of back pain catastrophizing on long-term outcomes following lumbar spondylolisthesis surgery. METHODS This study uses the Quality Outcomes Database (QOD) lumbar spondylolisthesis dataset and includes prospectively collected data from the 12 highest-enrolling clinical sites participating in the QOD lumbar module. The authors reviewed patients undergoing single-segment surgery for grade 1 degenerative lumbar spondylolisthesis. Severe baseline numeric rating scale for back pain (NRS-BP) scores (≥ 8) were classified as "catastrophizing," and mild to moderate pain scores (< 8) were classified as "non-catastrophizing." Patient-reported outcomes (PROs) were compared for catastrophizing versus non-catastrophizing patients at 60 months. Univariate and multivariate analyses were conducted to assess the impact of catastrophizing on PROs, with multivariate analysis controlling for variables initially reaching a p value < 0.10. RESULTS Of the 608 patients in this analysis, 260 (42.8%) experienced catastrophizing while 348 (57.2%) did not. Catastrophizing patients were significantly younger (59.9 ± 12.2 years vs 63.9 ± 11.7 years, p < 0.001), less often had ≥ 4 years of college education (31.2% vs 42.5%, p = 0.004), and more often used private insurance (58.8% vs 47.7%, p = 0.01). The catastrophizing cohort also had higher rates of depression (24.6% vs 17.0%, p = 0.02) and back pain predominance (45.4% vs 32.2%, p < 0.001). Surgical and perioperative characteristics did not significantly differ between cohorts. Although catastrophizing patients typically reported worse PRO scores at both baseline and 60 months, they demonstrated significantly greater improvement and minimal clinically important difference (MCID) achievement across almost all PROs at 60 months (p < 0.05). However, North American Spine Society (NASS) satisfaction scores at 60 months did not differ significantly between cohorts. Multivariate analysis found that catastrophizing significantly predicted 60-month NRS-BP change (β −1.45, 95% CI −1.81 to −1.09; p < 0.001) and MCID achievement (OR 1.98, 95% CI 1.52–2.58; p < 0.001) but not mean NRS-BP score or other metrics, including NASS satisfaction. CONCLUSIONS Despite presenting with worse baseline symptoms, patients with pain catastrophizing experienced substantial and clinically meaningful improvement following surgery for degenerative lumbar spondylolisthesis. Patient satisfaction was comparable between cohorts, reflecting a nuanced balance between greater absolute improvement and persistence of residual symptoms. These findings underscore that catastrophizing should not be viewed as a barrier to surgical success, while pointing to the need for proactive expectation setting and shared decision-making.
Defining cervical spondylotic myelopathy surgical endotypes using comorbidity clustering: a Quality Outcomes Database cervical spondylotic myelopathy study

Neurosurgical Focus | July 1, 2025 | Volume: 59 | Issue: 1 | Pages: E4

10.3171/2025.4.focus25207 | PMID 40591975

OBJECTIVE Coexisting medical conditions are increasingly prevalent in surgical populations. The impact of multiple comorbidities on patient-reported outcomes (PROs) and endotypes of frequently co-occurring conditions for cervical spondylotic myelopathy (CSM) remain unclear. This study explores whether CSM patients with multimorbidity have worse baseline and postoperative PROs and less functional improvement after surgery compared to those with few or no comorbidities. The authors also investigated whether distinct comorbidity endotypes exist among CSM surgical patients and whether they influence postoperative outcomes. METHODS The prospective Quality Outcomes Database (QOD) was used to assess patients undergoing surgery for CSM. Multimorbidity was defined as ≥ 2 chronic conditions, including diabetes, coronary artery disease, peripheral vascular disease, arthritis, chronic renal disease, chronic obstructive pulmonary disease, Parkinson’s disease, multiple sclerosis, depression, and anxiety. Baseline characteristics and 24-month PROs were assessed across multiple-comorbidity status, including modified Japanese Orthopaedic Association (mJOA), Neck Disability Index (NDI), visual analog scale for neck and arm pain, EQ-5D, and patient satisfaction scores. Clusters were identified from the full cohort using k-medoids, revealing subgroups with similar comorbidity endotypes. RESULTS The final cohort included 1141 CSM patients (83.1% reaching 24-month follow-up), with 761 (66.7%) having 0 or 1 comorbidity and 380 (33.3%) ≥ 2 comorbidities. The multimorbidity cohort was older (mean age 62.6 ± 11.2 vs 59.5 ± 12.0 years, p < 0.001), more likely to be female (52.9% vs 44.7%, p = 0.011), and had a higher BMI (mean 31.1 ± 6.7 vs 29.7 ± 6.2 kg/m 2 , p < 0.001). Multimorbidity patients exhibited worse mJOA, NDI, and EQ-5D scores at baseline and 24 months (p < 0.05). On multivariable analysis, the total number of comorbidities was not significantly associated with any PRO measures. Four comorbidity clusters were identified: low burden, arthritis, diabetes, and high burden. On one-way ANOVA, the baseline mJOA score was significantly different across clusters (p = 0.003). At 24 months, the mJOA score was significantly lower in the diabetes and high-burden endotypes. Twenty-four-month score change and minimal clinically important difference (MCID) achievement of all PROs remained similar across clusters (p > 0.05). CONCLUSIONS While patients with multimorbidity have worse baseline and postoperative PROs, they achieve similar functional and pain-related improvements following CSM surgery. Similarly, the comorbidity endotypes identified in this QOD cohort suggest that certain patterns of coexisting chronic conditions, such as overlapping diabetes and arthritis, are associated with different levels of disability but may not diminish the effectiveness of surgical intervention.
Gain of care independence following surgical intervention for cervical spondylotic myelopathy: a Quality Outcomes Database study

Journal of Neurosurgery: Spine | May 30, 2025 | Volume: 43 | Issue: 2 | Pages: 170-180

10.3171/2025.2.spine231237 | PMID 40446343

OBJECTIVE Chronic spinal degenerative diseases have been associated with reduced quality of life and dependency on others for personal needs and care. The change between preoperative and postoperative care dependency has yet to be explored in patients with cervical spondylotic myelopathy (CSM). In this retrospective study of a prospectively collected database, the authors evaluated the return to independence in performing self-care following surgical intervention for CSM. METHODS The CSM dataset of the Quality Outcomes Database (QOD) Spine CORe study group was queried. Care dependency was assessed using the personal care component of the Neck Disability Index (NDI) questionnaire, having an ordinal scale from 0 to 5, with 5 representing the inability to independently perform activities of daily living. Numeric rating scale (NRS) scores for arm pain and neck pain were recorded at a 24-months postoperative follow-up. Multivariable logistic regression analyses were performed to identify baseline risk factors for an inability to care for oneself and the symptoms leading to care dependency at 24 months postoperatively. Satisfaction with surgery was measured using the 4-point North American Spine Society (NASS) index. RESULTS Of the 1137 patients with CSM and baseline personal care scores, 167 (14.7%) were care dependent at baseline (NDI personal care score ≥ 3). Patients with care dependency at baseline were predominantly Medicare beneficiaries and had a high school or lower level of education. Long-term follow-up rates for this study were 82.5% for NDI, 84.8% for patient satisfaction with surgery, 82.4% for NRS arm pain, and 81.8% for NRS neck pain. Of the care-dependent patients, more than 80% became independently able to care for themselves by the 24-month follow-up. Patients with resolved care dependency at 24 months had demonstrated lower baseline NDI and NRS neck pain scores (p < 0.01 for both). Neck pain was significantly associated with care dependency at 24 months’ follow-up (p < 0.01). Patients who reported improvement in their ability to care for themselves noted higher postoperative satisfaction (NASS score 1–2) at the 3-month (89.4% vs 80.2%, p < 0.01) and 24-month (88.2% vs 67.4%, p < 0.01) follow-ups. CONCLUSIONS Fifteen percent of patients with CSM depended on others for care preoperatively. After surgery to treat CSM, 81.8% of those who had depended on others for care became independent. Patients with improvements in care dependency noted higher postoperative satisfaction at the 3-month and 24-month follow-ups. Patients with resolved care dependency on long-term follow-up had lower NDI and NRS neck pain scores at baseline. Surgery had a significant impact on patients’ attainment of independence.
A comparative study on the effect of age on Neck Disability Index improvement at 24 months after surgical intervention for cervical spondylotic myelopathy: a Quality Outcomes Database study

Journal of Neurosurgery: Spine | May 23, 2025 | Volume: 43 | Issue: 2 | Pages: 154-169

10.3171/2025.3.spine24598 | PMID 40408883

OBJECTIVE Cervical spondylotic myelopathy (CSM) is often accompanied by neck pain, which, along with more recognized neurological deficits like motor and sensory changes, significantly impacts patients’ quality of life. The authors examined whether age influences improvements in neck disability and related quality-of-life measures after surgery for CSM. Using the Neck Disability Index (NDI) as the primary outcome, they compared long-term outcomes at 24 months among patients aged ≥ 65, ≥75, and < 65 years, exploring the effects of surgical intervention on both pain-related disability and functional recovery in older adults. METHODS Using the Quality Outcomes Database, the authors conducted a detailed propensity score–matched analysis on cohorts aged ≥ 65 and ≥ 75 years compared with a < 65-year-old cohort while controlling for baseline NDI scores, other demographic variables, health status, underlying pathology, number of levels, indication for surgery, surgical approach, and type of surgery. Differences in NDI total and subdomain scores at 24 months postoperatively were the primary measures of improvement. Age-related variability in NDI differential was assessed. EQ-5D and calculated SF-6D were secondary measures. RESULTS Of the 1141 patients in the cohort (January 2016 to December 2018), 687 patients were < 65 years, 325 were 65 to < 75 years, and 129 were ≥ 75 years of age. After propensity score matching, 197 patients each were well matched in the ≥ 65-year (mean 71.4 years) and < 65-year (mean 55.3 years) cohorts; similarly, 57 patients each were matched in the ≥ 75-year (mean 78.3 years) and < 65-year (mean 55.8 years) cohorts. Improvements in NDI scores and subdomain scores, EQ-5D, and calculated SF-6D were consistent at 3, 12, and 24 months postoperatively across all cohorts. At 24 months, patients ≥ 65 years showed NDI score improvements (−14.7 ± 22.3) similar to those < 65 years (−13.0 ± 21.3, p = 0.454), and patients ≥ 75 years demonstrated NDI improvements (−15.0 ± 19.7) comparable to those < 65 years (−17.6 ± 20.4, p = 0.499). A sensitivity analysis for linear relationship found that NDI improvement was statistically greater in older patients (7.5 points every 30 years, p < 0.0001), but this difference was below the minimal clinically important difference. Other clinical outcomes were similar between cohorts. CONCLUSIONS Surgical intervention for CSM yields substantial and similar improvements in NDI scores and other metrics among various age groups, including those aged at least 65 and 75 years. These results highlight the effectiveness of surgery across a broad patient demographic, underscoring its value in treating CSM irrespective of age.
Are There Differences in 2-Year Outcomes Between Two-Level Anterior Cervical Diskectomy and Fusion Versus Single-Level Anterior Cervical Corpectomy and Fusion to Treat Cervical Myelopathy? A Quality Outcomes Database Study

Neurosurgery | May 19, 2025 | Volume: 97 | Issue: 5 | Pages: 1091-1099

10.1227/neu.0000000000003518 | PMID 40388528

BACKGROUND AND OBJECTIVES: There has been limited assessment between anterior cervical diskectomy and fusion (ACDF) and anterior cervical corpectomy and fusion (ACCF) on patient-reported outcome measures (PROMs) in the treatment of cervical spondylotic myelopathy. We sought to compare PROMs from two-level ACDF with single-level ACCF procedures. We evaluate these results in the context of minimum clinically important difference (MCID) thresholds, which have not been performed previously. METHODS: This retrospective analysis of prospectively collected data from the Quality Outcomes Database Spine Collaborative Research Study Group compared two-level ACDF and single-level ACCF at 3-, 12-, and 24 months postoperatively. PROMs included arm pain Numeric Rating Scale, neck pain Numeric Rating Scale, Neck Disability Index, and North American Spine Society Patient Satisfaction Index. Multivariate logistic regression was used to determine differences in perioperative outcomes, as well as the impact of two-level ACDF vs one-level ACCF on PROMs. MCID thresholds were based off previously established limits. RESULTS: Three hundred and thirty patients were included (236 ACDF, 94 ACCF), and the follow-up rate was 82% at 2 years. There was a significantly higher baseline age, American Society of Anesthesiologists grade, proportion of diabetes, osteoarthritis, ambulation dependence, and myelopathy severity in the ACCF cohort. On multivariable analysis, the ACCF group had greater average length of stay and estimated blood loss. There were no significant differences between reoperation rates or nonroutine discharge. There were similar rates of MCID achievement for PROMs at all time points. CONCLUSION: This study suggests that both ACDF and ACCF procedures for cervical spondylotic myelopathy are able to achieve similar, clinically meaningful improvements in PROMs by 2 years. Patients undergoing single-level ACCF have more estimated blood loss and longer length of stay, as well as worse baseline myelopathy. Both procedures have efficacious, durable outcomes. It is reasonable that other factors, such as radiographic characteristics and patient symptoms, may influence patient selection for ACDF vs ACCF.
Do Patients With High ASA Grades Benefit From CSM Surgery?

Clinical Spine Surgery | April 21, 2025 | Volume: 38 | Issue: 4 | Pages: 197-203

10.1097/bsd.0000000000001774 | PMID 40257936

Study Design: Analysis of prospectively collected data. Objective: To assess if systemic illness severity affects cervical spondylotic myelopathy (CSM) surgery outcomes. Summary of Background Data: It remains unclear if CSM patients with poor physical status/severe systemic illness benefit as much from surgery as those in good condition. Methods: Using the Quality Outcomes Database CSM cohort and the American Association of Anesthesiology (ASA) grade as a surrogate for illness burden, we compared patients with (ASA 3–4) and without (ASA 1–2) severe systemic illness, including rates of readmission and 24-month minimal clinically important differences (MCID) achievement for patient-reported outcomes (PROs)—numerical rating score (NRS) arm and neck pain, neck pain-related disability (NDI), and quality of life (EQ-5D). Results: Of 1141 CSM patients, 1062 had ASA grades recorded. Of these 1062 patients, 70.2% had a 2-year follow-up for mJOA, and 81%–84% had a follow-up for NRS arm and neck, NDI, and EQ-5D. Five hundred twenty-one patients (49.1%) had mild (ASA 1–2) and 541 (50.9%) had severe systemic illness (ASA 3–4). The severe disease cohort was older (63.3±11.0 vs. 57.4±11.7), had higher BMI (31.4±7.0 vs. 28.9±5.6), had more comorbidities (diabetes, coronary artery disease, depression), and had less independent ambulation (71.3% vs. 90.6%) ( P <0.05). At baseline, severe disease patients had worse NRS arm (5.2±3.5 vs. 4.7±3.4) and neck (5.5±3.2 vs. 5.1±3.3) pain, NDI (40.5±20.1 vs. 36.8±21.0), and EQ-5D (0.53±0.22 vs. 0.59±0.22) scores ( P <0.05). Perioperatively, the severe disease cohort had longer hospitalizations (2.4±2.6 vs. 1.7±2.0 days) and increased nonhome discharges (17% vs. 5%) ( P <0.05). The severe disease cohort had higher 90-day readmissions (7.6% vs. 2.5%), including surgery-related (3.7% vs. 1.5%) and non–surgery-related reasons (3.9% vs. 1.0%) ( P <0.05). On multivariate analysis, increased ASA grade was significantly associated with 90-day readmissions (OR: 2.55 per 1-grade increase, 95% CI: 1.38–4.83). However, both severe and mild disease cohorts had similarly high rates of achieving 2-year MCID for mJOA (67.5% vs. 66.0%), NRS arm (72.0% vs. 74.1%), neck (69.5% vs. 69.4%) pain, NDI (63.1% vs. 68.1%), and EQ-5D (67.9% vs. 66.9%) ( P >0.05). Conclusion: Patients with severe systemic illness (higher ASA) have worse baseline PROs and higher 90-day readmissions. However, they achieve similar MCID rates for mJOA and all measured PROs 2 years postoperatively.
Impact of the day of the week on clinical outcomes following anterior cervical discectomy and fusion surgery

Journal of Neurosurgery: Spine | March 22, 2025 | Volume: 42 | Issue: 6 | Pages: 737-747

10.3171/2024.11.spine24609 | PMID 40117661

OBJECTIVE Previous research suggests elective surgical procedures performed later in the week have worse outcomes. This study investigated whether the day of the week on which elective anterior cervical discectomy and fusion (ACDF) surgery was performed impacts clinical outcomes. METHODS Using data from the Quality Outcomes Database, a nationwide, multicenter prospective registry, this study included patients undergoing elective ACDF for cervical spondylosis. Patients were categorized into groups based on the surgery day (early week, Monday and Tuesday; late week, Thursday and Friday). Analyzed outcomes included postoperative complications, readmissions, reoperations, and patient-reported outcomes. Statistical methods included the independent t-test, Pearson’s chi-square test, and multivariable logistic regression. RESULTS The study analyzed 19,818 patients, with 41.7% undergoing surgery early in the week and 36.9% later. There were no significant differences in 30-day mortality, readmissions, or reoperations between the two groups. Early-week surgical procedures were associated with a higher incidence of postoperative dysphagia requiring nasogastric tubes (0.6% vs 0.3%, p = 0.02) and a higher incidence of vocal cord paralysis (0.5% vs 0.3%, p = 0.01). The data indicate a surgical selection bias with more complex surgical procedures and higher risk patients typically scheduled earlier in the week, which likely contributed to the increased rates of dysphagia. Conversely, patients who underwent operations on Fridays were more likely to be discharged on the same day compared to those earlier in the week (p = 0.02), without a significant difference in length of stay overall. Surgical procedures performed later in the week were more likely to be performed at ambulatory surgical centers rather than inpatient facilities (p < 0.01), indicating a strategic selection of healthier patients for end-of-week procedures. CONCLUSIONS The day of elective ACDF surgery does not affect mortality, readmissions, or reoperation rates. However, early-week surgical procedures may see slightly higher rates of postoperative dysphagia and vocal cord paralysis, likely due to the scheduling of more complex cases or higher risk patients during these days. Overall, the authors’ data confirm that day of surgery does not influence overall patient recovery significantly. This information is useful for surgical planning and for providing patient reassurance that the day of the week does not significantly impact surgical outcomes.