Practice Variation between Salaried and Fee-for-Service Surgeons for Lumbar Surgery.

OBJECTIVE: To examine differences in surgical practices between salaried and fee-for-service (FFS) surgeons for two common degenerative spine conditions. Surgeons may offer different treatments for similar conditions on the basis of their compensation mechanism. METHODS: The study assessed the practices of 63 spine surgeons across eight Canadian provinces (39 FFS surgeons and 24 salaried) who performed surgery for two lumbar conditions: stable spinal stenosis and degenerative spondylolisthesis. The study included a multicenter, ambispective review of consecutive spine surgery patients enrolled in the Canadian Spine Outcomes and Research Network registry between October 2012 and July 2018. The primary outcome was the difference in type of procedures performed between the two groups. Secondary study variables included surgical characteristics, baseline patient factors, and patient-reported outcome. RESULTS: For stable spinal stenosis (n = 2234), salaried surgeons performed statistically fewer uninstrumented fusion (p < 0.05) than FFS surgeons. For degenerative spondylolisthesis (n = 1292), salaried surgeons performed significantly more instrumentation plus interbody fusions (p < 0.05). There were no statistical differences in patient-reported outcomes between the two groups. CONCLUSIONS: Surgeon compensation was associated with different approaches to stable lumbar spinal stenosis and degenerative lumbar spondylolisthesis. Salaried surgeons chose a more conservative approach to spinal stenosis and a more aggressive approach to degenerative spondylolisthesis, which highlights that remuneration is likely a minor determinant in the differences in practice of spinal surgery in Canada. Further research is needed to further elucidate which variables, other than patient demographics and financial incentives, influence surgical decision-making.

Temporal analysis of complication rates of cervical spine surgery for degenerative spine disease between younger and older cohorts using the CSORN registry: Is age just a number?

STUDY DESIGN: An ambispective review of consecutive cervical spine surgery patients enrolled in the Canadian Spine Outcomes and Research Network (CSORN) between January 2015 and September 2019. PURPOSE: To compare complication rates of degenerative cervical spine surgery over time between older (> 65) and younger age groups (< 65). More elderly people are having spinal surgery. Few studies have examined the temporal nature of complications of cervical spine surgery by patient age groups. METHODS: Adverse events were collected prospectively using adverse event forms. Binary logistic regression analysis was utilized to assess associations between risk modifiers and adverse events at the intra-, peri-operative and 3 months post-surgery. RESULTS: Of the 761 patients studied (age < 65, n = 581 (76.3%) and 65 + n = 180 (23.7%), the intra-op adverse events were not significantly different; < 65 = 19 (3.3%) vs 65 + = 11 (6.1%), p < 0.087. Peri-operatively, the < 65 group had significantly lower percentage of adverse events (65yrs (11.2%) vs. 65 + = (26.1%), p < 0.001). There were no differences in rates of adverse events at 3 months post-surgery (< 65 = 39 (6.7%) vs. 65 + = 12 (6.7%), p < 0.983). Less blood loss (OR = 0.99, p < 0.010) and shorter length of hospital stay (OR = 0.97, p < 0.025) were associated with not having intra-op adverse events. Peri-operatively, > 1 operated level (OR = 1.77, p < 0.041), shorter length of hospital stay (OR = 0.86, p < 0.001) and being younger than 65 years (OR = 2.11, p < 0.006) were associated with not having adverse events. CONCLUSION: Following degenerative cervical spine surgery, the older and younger age groups had significantly different complication rates at peri-operative time points, and the intra-operative and 3-month post-operative complication rates were similar in the groups.

Variation in surgical treatment of degenerative spondylolisthesis in Canada: surgeon assessment of stability and impact on treatment.

INTRODUCTION: Controversy exists regarding the optimal surgical treatment of degenerative lumbar spondylolisthesis (DS). Not all DS patients are the same, and the degree to which inherent stability may dictate treatment is unknown. The purpose of this study was to determine the variability in surgical approach relative to surgeon classified stability. The secondary objective was to compare patient-reported outcomes (PROs) across different surgical techniques and grades of stability. METHODS: Patients prospectively enrolled from eleven tertiary care institutions and followed from 2015 to 2019. The surgical technique was at the surgeon's discretion. Surgeons were asked to grade the degree of instability based on the degenerative spondylolisthesis instability classification system (DSIC). DSIC categorizes three different types (I-stable, II-potentially unstable, and III-unstable). One-year changes in PROs were compared between each group. Multivariable regression was used to identify any characteristics that explained variability in treatment. RESULTS: There were 323 patients enrolled in this study. Surgeons' stability classification versus procedure [decompression alone (D)/decompression and posterolateral fusion (D-PL)/and decompression with posterior/transforaminal lumbar interbody fusion (D-PLIF/TLIF)] were as follows: type I (n = 91): D-41%/D-PL-13%/D-PLIF/TLIF-46%; type II (n = 175): D-23%/D-PL-17%/D-PLIF/TLIF-60%; and type III (n = 57):(D-0%/D-PL-14%/D-PLIF/TLIF-86%). Type I patients undergoing D-PL had some improvements in EQ-5D and NRS versus those undergoing D-PLIF/TLIF but otherwise there were no other significant differences between groups. Regression analysis demonstrated advanced age (OR = 1.06, CI 1.02-10.12) and type I (OR = 2.61, CI 1.17-5.81) were associated with receiving decompression surgery alone. CONCLUSIONS: There exists considerable variation in surgical management of DS in Canada. Given similar PROs in two of the three groups, there is potential to tailor surgical intervention and improve resource utilization.

Opioid use trends in patients undergoing elective thoracic and lumbar spine surgery.

Background: Opioid use in North America has increased rapidly in recent years. Preoperative opioid use is associated with several negative outcomes. Our objectives were to assess patterns of opioid use over time in Canadian patients who undergo spine surgery and to determine the effect of spine surgery on 1-year postoperative opioid use. Methods: A retrospective analysis was performed on prospectively collected data from the Canadian Spine Outcomes and Research Network for patients undergoing elective thoracic and lumbar surgery. Self-reported opioid use at baseline, before surgery and at 1 year after surgery was compared. Baseline opioid use was compared by age, sex, radiologic diagnosis and presenting complaint. All patients meeting eligibility criteria from 2008 to 2017 were included. Results: A total of 3134 patients provided baseline opioid use data. No significant change in the proportion of patients taking daily (range 32.3%-38.2%) or intermittent (range 13.7%-22.5%) opioids was found from pre-2014 to 2017. Among patients who waited more than 6 weeks for surgery, the frequency of opioid use did not differ significantly between the baseline and preoperative time points. Significantly more patients using opioids had a chief complaint of back pain or radiculopathy than neurogenic claudication (p < 0.001), and significantly more were under 65 years of age than aged 65 years or older (p < 0.001). Approximately 41% of patients on daily opioids at baseline remained so at 1 year after surgery. Conclusion: These data suggest that additional opioid reduction strategies are needed in the population of patients undergoing elective thoracic and lumbar spine surgery. Spine surgeons can be involved in identifying patients taking opioids preoperatively, emphasizing the risks of continued opioid use and referring patients to appropriate evidence-based treatment programs.

Contexte: En Amérique du Nord, l'utilisation d'opioïdes a augmenté rapidement dans les dernières années. La prise d'opioïdes en période préopératoire est associée à plusieurs issues négatives. Cette étude visait à évaluer l'évolution des tendances dans l'utilisation d'opioïdes des patients canadiens ayant subi une chirurgie spinale, et de déterminer les effets de la chirurgie sur leur utilisation 1 an après l'opération. Méthodes: Une analyse rétrospective a été réalisée à partir de données recueillies de manière prospective par le Canadian Spine Outcomes and Research Network pour les patients ayant subi une chirurgie thoracique ou une chirurgie spinale élective. On a comparé l'utilisation autodéclarée d'opioïdes au début du suivi, avant la chirurgie et 1 an après la chirurgie. L'utilisation d'opioïdes au départ a été comparée selon le sexe, l'âge, le diagnostic radiologique et le motif de consultation. Entre 2008 et 2017, tous les patients satisfaisant aux critères d'admissibilités ont été inclus dans l'étude. Résultats: Au total, 3134 patients ont fourni des données sur leur prise d'opioïdes au début du suivi. Il n'y avait pas de changement significatif dans la proportion de patients utilisant quotidiennement (32,3 % à 38,2 %) ou occasionnellement (13,7 % à 22,5 %) des opioïdes entre les patients à l'étude avant 2014 et ceux à l'étude de 2014 à 2017. Parmi les patients qui ont attendu plus de 6 semaines avant la chirurgie, la fréquence de la prise d'opioïdes n'a pas changé de manière significative entre le début du suivi et la rencontre préopératoire. Une proportion significativement plus grande de patients qui utilisaient des opioïdes consultaient principalement pour des douleurs au dos ou une radiculopathie que pour une claudication neurogène (p < 0,001), et il y avait une proportion significativement plus grande de patients de moins de 65 ans qui utilisaient des opioïdes que de patients de 65 ans ou plus (p < 0,001). Environ 41 % des patients qui prenaient quotidiennement des opioïdes au départ le faisaient aussi 1 an après la chirurgie. Conclusion: Ces données suggèrent que des stratégies supplémentaires de réduction de l'utilisation d'opioïdes sont nécessaires pour les patients qui subissent une chirurgie thoracique ou une chirurgie spinale élective. Il est possible de demander aux chirurgiens spécialisés dans ce domaine de repérer les patients qui prennent des opioïdes avant l'opération, puisque l'utilisation prolongée comporte des risques, et de les aiguiller vers un programme de traitement adéquat et fondé sur des données probantes.

Consultation and Surgical Wait Times in Cervical Spondylotic Myelopathy.

BACKGROUND: Cervical spondylotic myelopathy (CSM) is the leading cause of spinal cord impairment. In a public healthcare system, wait times to see spine specialists and eventually access surgical treatment for CSM can be substantial. The goals of this study were to determine consultation wait times (CWT) and surgical wait times (SWT), and identify predictors of wait time length. METHODS: Consecutive patients enrolled in the Canadian Spine Outcomes and Research Network (CSORN) prospective and observational CSM study from March 2015 to July 2017 were included. A data-splitting technique was used to develop and internally validate multivariable models of potential predictors. RESULTS: A CSORN query returned 264 CSM patients for CWT. The median was 46 days. There were 31% mild, 35% moderate, and 33% severe CSM. There was a statistically significant difference in median CWT between moderate and severe groups; 207 patients underwent surgical treatment. Median SWT was 42 days. There was a statistically significant difference in SWT between mild/moderate and severe groups. Short symptom duration, less pain, lower BMI, and lower physical component score of SF-12 were predictive of shorter CWT. Only baseline pain and medication duration were predictive of SWT. Both CWT and SWT were shorter compared to a concurrent cohort of lumbar stenosis patients (p <0.001). CONCLUSIONS: Patients with shorter duration (either symptoms or medication) and less neck pain waited less to see a spine specialist in Canada and to undergo surgical treatment. This study highlights some of the obstacles to overcome in expedited care for this patient population.

Temps d'attente pour obtenir une consultation et une intervention chirurgicale dans le cas de lamyélopathie spondylotique cervicale. Contexte : La myélopathie spondylotique cervicale (MSC) est la principale cause des troubles de la moelle épinière. Dans un régime public de santé, les temps d'attente pour voir des spécialistes et, le cas échéant, pour avoir accès à un traitement chirurgical dans le cas de la MSC peuvent être considérables. Cette étude comporte deux objectifs : d'une part, déterminer les temps d'attente pour une consultation (TAC) et pour une intervention chirurgicale (TAIC) ; d'autre part, identifier les variables prédictives des temps d'attente. Méthodes : C'est dans le cadre du Canadian Spine Outcomes and Research Network (CSORN) que cette étude observationnelle prospective a été effectuée. Y ont participé des patients vus un à la suite de l'autre entre mars 2015 et juillet 2017. À cet égard, nous avons utilisé la méthode de fractionnement des données (data-splitting technique) pour développer et valider à l'interne des modèles concernant nos variables prédictives. Résultats : Les données du CSORN montrent que 264 patients atteints de MSC sont parvenus à obtenir une consultation. Leur TAC médian a été de 46 jours. Sur ces 264 patients, 31 % étaient atteints d'une forme légère de MSC ; 35 %, d'une forme modérée ; et 33 %, d'une forme grave. Une différence statistique notable est apparue en ce qui regarde le TAC médian du groupe de patients atteints de la forme modérée de la maladie et celui du groupe de patients atteints de la forme grave. Notons par ailleurs que 207 patients ont pu subir une intervention chirurgicale. Leur TAIC médian a été de 42 jours. Une différence statistique notable est apparue entre les groupes de patients atteints des formes légère/modérée et celui incluant des patients atteints de la forme grave. Des symptômes de courte durée, moins de douleurs ressenties, de bas IMC et des scores plus bas au SF-12 en matière de santé physique ont constitué des variables prédictives d'un TAC plus court. Les seules variables ayant pu prédire les TAIC ont été le niveau de douleur avant traitement et la durée d'un traitement médical. Enfin, tant les TAC que les TAIC des patients atteints de MSC se sont révélés plus courts que ceux d'une cohorte de patients atteints de sténose du canal lombaire (p < 0,001) étudiée simultanément. Conclusions : En somme, les patients dont la durée des symptômes ou du traitement médical était plus courte, de même que ceux ayant moins souffert de cervicalgie, ont moins attendu au Canada pour voir un spécialiste de la moelle épinière et subir une intervention chirurgicale. Cette étude met donc en relief certains obstacles à une offre de services rapides pour cette catégorie de patients.

Anterior vs Posterior Surgery for Patients With Degenerative Cervical Myelopathy: An Observational Study From the Canadian Spine Outcomes and Research Network.

BACKGROUND AND OBJECTIVES: The advantages and disadvantages of anterior vs posterior surgical approaches for patients with progressive degenerative cervical myelopathy (DCM) remain uncertain. Our primary objective was to evaluate patient-reported disability at 1 year after surgery. Our secondary objectives were to evaluate differences in patient profiles selected for each approach in routine clinical practice and to compare neurological function, neck and arm pain, health-related quality of life, adverse events, and rates of reoperations. METHODS: We analyzed data from patients with DCM who were enrolled in an ongoing multicenter prospective observational cohort study. We controlled for differences in baseline characteristics and numbers of spinal levels treated using multivariable logistic regression. Adverse events were collected according to the Spinal Adverse Events Severity protocol. RESULTS: Among 559 patients, 261 (47%) underwent anterior surgery while 298 (53%) underwent posterior surgery. Patients treated posteriorly had significantly worse DCM severity and a greater number of vertebral levels involved. After adjusting for confounders, there was no significant difference between approaches for odds of achieving the minimum clinically important difference for the Neck Disability Index (odds ratio 1.23, 95% CI 0.82 to 1.86, P = .31). There was also no significant difference for change in modified Japanese Orthopedic Association scores, and differences in neck and arm pain and health-related quality of life did not exceed minimum clinically important differences. Patients treated anteriorly experienced greater rates of dysphagia, whereas patients treated posteriorly experienced greater rates of wound complications, neurological complications, and reoperations. CONCLUSION: Patients selected for posterior surgery had worse DCM and a greater number of vertebral levels involved. Despite this, anterior and posterior surgeries were associated with similar improvements in disability, neurological function, pain, and quality of life. Anterior surgery had a more favorable profile of adverse events, which suggests it might be a preferred option when feasible.

Factors associated with increased length of stay in degenerative cervical spine surgery: a cohort analysis from the Canadian Spine Outcomes and Research Network.

OBJECTIVE: Postoperative length of stay (LOS) significantly contributes to healthcare costs and resource utilization. The primary goal of this study was to identify patient, clinical, surgical, and institutional variables that influence LOS after elective surgery for degenerative conditions of the cervical spine. The secondary objectives were to examine the variability in LOS and institutional practices used to decrease LOS. METHODS: This was a multicenter observational retrospective cohort study of patients enrolled in the Canadian Spine Outcomes and Research Network (CSORN) between January 2015 and October 2020 who underwent elective anterior cervical discectomy and fusion (ACDF) (1-3 levels) or posterior cervical fusion (PCF) (between C2 and T2) with/without decompression for degenerative conditions of the cervical spine. Prolonged LOS was defined as LOS greater than the median for the ACDF and PCF populations. The principal investigators at each participating CSORN healthcare institution completed a survey to capture institutional practices implemented to reduce postoperative LOS. RESULTS: In total, 1228 patients were included (729 ACDF and 499 PCF patients). The median (IQR) LOS for ACDF and PCF were 1.0 (1.0) day and 5.0 (4.0) days, respectively. Predictors of prolonged LOS after ACDF were female sex, myelopathy diagnosis, lower baseline SF-12 mental component summary score, multilevel ACDF, and perioperative adverse events (AEs) (p < 0.05). Predictors of prolonged LOS after PCF were nonsmoking status, education less than high school, lower baseline numeric rating scale score for neck pain and EQ5D score, higher baseline Neck Disability Index score, and perioperative AEs (p < 0.05). Myelopathy did not significantly predict prolonged LOS within the PCF cohort after multivariate analysis. Of the 8 institutions (57.1%) with an enhanced recovery after surgery (ERAS) protocol or standardized protocol, only 3 reported using an ERAS protocol specific to patients undergoing ACDF or PCF. CONCLUSIONS: Patient and clinical factors predictive of prolonged LOS after ACDF and PCF are highly variable, warranting individual consideration for possible mitigation. Perioperative AEs remained a consistent independent predictor of prolonged LOS in both cohorts, highlighting the importance of preventing intra- and postoperative complications.

Pre-operative expectations of patients with degenerative cervical myelopathy: an observational study from the Canadian Spine Outcomes and Research Network.

BACKGROUND: Despite an abundance of literature on degenerative cervical myelopathy (DCM), little is known about pre-operative expectations of these patients. PURPOSE: The primary objective was to describe patient pre-operative expectations. Secondary objectives included identifying patient characteristics associated with high pre-operative expectations and to determine if expectations varied depending on myelopathy severity. STUDY DESIGN: This was a retrospective study of a prospective multicenter, observational cohort of patients with DCM. PATIENT SAMPLE: Patients who consented to undergo surgical treatment between January 2019 and September 2022 were included. OUTCOMES MEASURES: An 11-domain expectation questionnaire was completed pre-operatively whereby patients quantified the expected change in each domain. METHODS: The most important expected change was captured. A standardized expectation score was calculated as the sum of each expectation divided by the maximal possible score. The high expectation group was defined by patients who had an expectation score above the 75th percentile. Predictors of patients with high expectations were determined using multivariable logistic regression models. RESULTS: There were 262 patients included. The most important patient expectation was preventing neurological worsening (40.8%) followed by improving balance when standing or walking (14.5%), improving independence in everyday activities (10.3%), and relieving arm tingling, burning and numbness (10%). Patients with mild myelopathy were more likely to select no worsening as the most important expected change compared to patients with severe myelopathy (p<.01). Predictors of high patient expectations were: having fewer comorbidities (OR -0.30 for every added comorbidity, 95% CI -0.59 to -0.10, p=.01), a shorter duration of symptoms (OR 0.92, 95% CI 0.35-1.19, p=.02), no contribution from "failure of other treatments" on the decision to undergo surgery (OR 1.49, 95% CI 0.56-2.71, p=.02) and more severe neck pain (OR 0.19 for 1 point increase, 95% CI 0.05-0.37, p=.01). CONCLUSIONS: Most patients undergoing surgery for DCM expect prevention of neurological decline, better functional status, and improvement in their myelopathic symptoms. Stopping neurological deterioration is the most important expected outcomes by patients.

The Effects of Peri-Operative Adverse Events on Clinical and Patient-Reported Outcomes After Surgery for Degenerative Cervical Myelopathy: An Observational Cohort Study from the Canadian Spine Outcomes and Research Network.

BACKGROUND AND OBJECTIVES: There is a lack of data examining the effects of perioperative adverse events (AEs) on long-term outcomes for patients undergoing surgery for degenerative cervical myelopathy. We aimed to investigate associations between the occurrence of perioperative AEs and coprimary outcomes: (1) modified Japanese Orthopaedic Association (mJOA) score and (2) Neck Disability Index (NDI) score. METHODS: We analyzed data from 800 patients prospectively enrolled in the Canadian Spine Outcomes and Research Network multicenter observational study. The Spine AEs Severity system was used to collect intraoperative and postoperative AEs. Patients were assessed at up to 2 years after surgery using the NDI and the mJOA scale. We used a linear mixed-effect regression to assess the influence of AEs on longitudinal outcome measures as well as multivariable logistic regression to assess factors associated with meeting minimal clinically important difference (MCID) thresholds at 1 year. RESULTS: There were 167 (20.9%) patients with minor AEs and 36 (4.5%) patients with major AEs. The occurrence of major AEs was associated with an average increase in NDI of 6.8 points (95% CI: 1.1-12.4, P = .019) and reduction of 1.5 points for mJOA scores (95% CI: -2.3 to -0.8, P < .001) up to 2 years after surgery. Occurrence of major AEs reduced the odds of patients achieving MCID targets at 1 year after surgery for mJOA (odds ratio 0.23, 95% CI: 0.086-0.53, P = .001) and for NDI (odds ratio 0.34, 95% CI: 0.11-0.84, P = .032). CONCLUSION: Major AEs were associated with reduced functional gains and worse recovery trajectories for patients undergoing surgery for degenerative cervical myelopathy. Occurrence of major AEs reduced the probability of achieving mJOA and NDI MCID thresholds at 1 year. Both minor and major AEs significantly increased health resource utilization by reducing the proportion of discharges home and increasing length of stay.

Development of a computer-based clinical decision support tool for selecting appropriate rehabilitation interventions for injured workers.

PURPOSE: To develop a classification algorithm and accompanying computer-based clinical decision support tool to help categorize injured workers toward optimal rehabilitation interventions based on unique worker characteristics. METHODS: Population-based historical cohort design. Data were extracted from a Canadian provincial workers' compensation database on all claimants undergoing work assessment between December 2009 and January 2011. Data were available on: (1) numerous personal, clinical, occupational, and social variables; (2) type of rehabilitation undertaken; and (3) outcomes following rehabilitation (receiving time loss benefits or undergoing repeat programs). Machine learning, concerned with the design of algorithms to discriminate between classes based on empirical data, was the foundation of our approach to build a classification system with multiple independent and dependent variables. RESULTS: The population included 8,611 unique claimants. Subjects were predominantly employed (85 %) males (64 %) with diagnoses of sprain/strain (44 %). Baseline clinician classification accuracy was high (ROC = 0.86) for selecting programs that lead to successful return-to-work. Classification performance for machine learning techniques outperformed the clinician baseline classification (ROC = 0.94). The final classifiers were multifactorial and included the variables: injury duration, occupation, job attachment status, work status, modified work availability, pain intensity rating, self-rated occupational disability, and 9 items from the SF-36 Health Survey. CONCLUSIONS: The use of machine learning classification techniques appears to have resulted in classification performance better than clinician decision-making. The final algorithm has been integrated into a computer-based clinical decision support tool that requires additional validation in a clinical sample.

Patient-Reported Outcomes Following Surgery for Lumbar Disc Herniation: Comparison of a Universal and Multitier Health Care System.

STUDY DESIGN: Ambispective cohort study. OBJECTIVE: Canada has a government-funded universal health care system. The United States utilizes a multitier public and private system. The objective is to investigate differences in clinical outcomes between those surgically treated for lumbar disc herniation in a universal health care and multitier health system. METHODS: Surgical lumbar disc herniation patients enrolled in the Canadian Spine Outcome Research Network (CSORN) were compared with the surgical cohort enrolled in the Spine Patients Outcome Research Trial (SPORT) study. Baseline demographics and spine-related patient-reported outcomes (PROs) were compared at 3 months and 1 year post-operatively. RESULTS: The CSORN cohort consisted of 443 patients; the SPORT cohort had 763 patients. Patients in the CSORN cohort were older (46.4 ± 13.5 vs 41.0 ± 10.8, P < .001) and were more likely to be employed (69.5% vs 60.3%, P = .003). The CSORN cohort demonstrated significantly greater rates of satisfaction after surgery at 3 months (87.2% vs 64.8%, P < .0001) and 1 year (85.6% vs 69.6%, P < .0001). Improvements in back and leg pain followed similar trajectories in the two cohorts, but there was less improvement on ODI in the CSORN cohort (P < .01). On multivariable logistic regression, the CSORN cohort was a significant independent predictor of patient satisfaction at 1-year follow-up (P < .001). CONCLUSIONS: Despite less improvement on ODI, patients enrolled in CSORN, as part of a universal health care system, reported higher rates of satisfaction at 3 months and 1 year post-operatively compared to patients enrolled within a multitier health system.

Minimally Invasive Tubular Lumbar Discectomy Versus Conventional Open Lumbar Discectomy: An Observational Study From the Canadian Spine Outcomes and Research Network.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: We evaluated the effectiveness of minimally invasive (MIS) tubular discectomy in comparison to conventional open surgery among patients enrolled in the Canadian Spine Outcomes and Research Network (CSORN). METHODS: We performed an observational analysis of data that was prospectively collected. We implemented Minimum Clinically Important Differences (MCIDs), and we adjusted for potential confounders with multiple logistic regression. Adverse events were collected according to the Spinal Adverse Events Severity (SAVES) protocol. RESULTS: Three hundred thirty-nine (62%) patients underwent MIS tubular discectomy and 211 (38%) underwent conventional open discectomy. There were no significant differences between groups for improvement of leg pain and disability, but the MIS technique was associated with reduced odds of achieving the MCID for back pain (OR 0.66, 95% CI 0.44 to 0.99, P < 0.05). We identified statistically significant differences in favor of MIS for each of operating time (MIS mean (SD) 72.2 minutes (30.0) vs open 93.5 (40.9)), estimated blood loss (MIS 37.9 mL (36.7) vs open 76.8 (71.4)), length of stay in hospital (MIS 73% same-day discharge vs open 40%), rates of incidental durotomy (MIS 4% vs open 8%), and wound-related complications (MIS 3% vs open 9%); but not for overall rates of reoperation. CONCLUSIONS: Open and MIS techniques yielded similar improvements of leg pain and disability at up to 12 months of follow-up, but MIS patients were less likely to experience improvement of associated back pain. Small differences favored MIS for operating time, blood loss, and adverse events but may have limited clinical importance.

Timing of Recovery After Surgery for Patients With Degenerative Cervical Myelopathy: An Observational Study From the Canadian Spine Outcomes and Research Network.

BACKGROUND: The time course over which postoperative neurological recovery occurs after surgery for degenerative cervical myelopathy occurs is poorly understood. OBJECTIVE: To determine the time point at which patients experience significant neurological improvement. METHODS: We reviewed data from an ongoing prospective multicenter cohort study. We measured neurological function at 3 months, 1 year, and 2 years after surgery using the modified Japanese Orthopedic Association (mJOA) scale. We implemented minimal clinical important differences (MCIDs) to guide interpretation of mJOA scores, and we used 1-way analysis of variance to compare changes between follow-up intervals. RESULTS: Among 330 patients, the mean overall mJOA improved from 12.9 (SD 2.6) to 14.6 (SD 2.4) at 3 months, 14.7 (SD 2.4) at 1 year, and 14.8 (SD 2.5) at 2 years. The difference in means was statistically significant (P < .01) at the interval from baseline to 3 months postoperatively, but not from 3 months to 1 year or 1 year to 2 years. The MCID was reached by 161 patients at 3 months, 32 more at 1 year, and 15 more at 2 years, with a statistically significant difference only at 3 months. Patients with moderate or severe disease reached the MCID more frequently than those with mild disease. CONCLUSION: Among patients who underwent surgery for degenerative cervical myelopathy, most significant neurological improvement occurred by 3 months after surgery. These findings will facilitate valid discussions about postoperative expectations during shared clinical decision making between patients and their surgeons.

Does Ending a Posterior Construct Proximally at C2 Versus C3 Impact Patient Reported Outcomes in Degenerative Cervical Myelopathy Patients up to 24 months After the Surgery?

STUDY DESIGN: Retrospective cohort study. OBJECTIVES: The primary objective was to evaluate the impact of the upper instrumented level (UIV) being at C2 vs C3 in posterior cervical construct on patient reported outcomes (PROs) up to 24 months after surgery for cervical degenerative myelopathy (DCM). Secondary objectives were to compare operative time, intra-operative blood loss (IOBL), length of stay (LOS), adverse events (AEs) and re-operation. METHODOLOGY: Patients who underwent a posterior cervical instrumented fusion (3 and + levels) with a C2 or C3 UIV, with 24 months follow-up were analyzed. PROs (NDI, EQ5D, SF-12 PCS/MCS, NRS arm/neck pain) were compared using ANCOVA. Operative duration, IOBL, AEs, and re-operation were compared. Subgroup analysis was performed on patient presenting with pre-operative malalignment (cervical sagittal vertical axis ≥40 mm and/or T1slope- cervical lordosis >15°). RESULTS: 173 patients were included, of which 41 (24%) had a C2 UIV and 132 (76%) a C3 UIV. There was no statistically significant difference between the groups for the changes in PROs up to 24 months. Subgroup analysis of patients with pre-operative malalignment showed a trend towards greater improvement in the NDI at 12 months with a C2 UIV (P = .054). Operative time, IOBL and peri-operative AEs were more in C2 group (P < .05). There was no significant difference in LOS and re-operation (P > .05). CONCLUSION: In this observational study, up to 24 months after surgery for posterior cervical fusion in DCM greater than 3 levels, PROs appear to evolve similarly.

Minimally Invasive vs. Open Surgery for Lumbar Spinal Stenosis in Patients with Diabetes - A Canadian Spine Outcomes and Research Network Study.

STUDY DESIGN: Retrospective cohort. OBJECTIVES: To compare outcomes of minimally invasive surgery (MIS) vs open surgery (OPEN) for lumbar spinal stenosis (LSS) in patients with diabetes. METHODS: Patients with diabetes who underwent spinal decompression alone or with fusion for LSS within the Canadian Spine Outcomes and Research Network (CSORN) database were included. MIS vs OPEN outcomes were compared for 2 cohorts: (1) patients with diabetes who underwent decompression alone (N = 116; MIS n = 58 and OPEN n = 58), (2) patients with diabetes who underwent decompression with fusion (N = 108; MIS n = 54 and OPEN n = 54). Modified Oswestry Disability Index (mODI) and back and leg pain were compared at baseline, 6-18 weeks, and 1-year post-operation. The number of patients meeting minimum clinically important difference (MCID) or minimum pain/disability at 1-year was compared. RESULTS: MIS approaches had less blood loss (decompression alone difference 100 mL, P = .002; with fusion difference 244 mL, P < .001) and shorter length of stay (LOS) (decompression alone difference 1.2 days, P = .008; with fusion difference 1.2 days, P = .026). MIS compared to OPEN decompression with fusion had less patients experiencing adverse events (AEs) (difference 13 patients, P = .007). The MIS decompression with fusion group had lower 1-year mODI (difference 14.5, 95% CI [7.5, 21.0], P < .001) and back pain (difference 1.6, 95% CI [.6, 2.7], P = .002) compared to OPEN. More patients in the MIS decompression with fusion group exceeded MCID at 1-year for mODI (MIS 75.9% vs OPEN 53.7%, P = .028) and back pain (MIS 85.2% vs OPEN 70.4%, P = .017). CONCLUSIONS: MIS approaches were associated with more favorable outcomes for patients with diabetes undergoing decompression with fusion for LSS.

Deterioration After Surgery for Degenerative Cervical Myelopathy: An Observational Study From the Canadian Spine Outcomes and Research Network.

STUDY DESIGN: A Prospective cohort study. OBJECTIVE: To investigate the incidence, etiology, and outcomes of patients who experience neurological deterioration after surgery for Degenerative Cervical Myelopathy (DCM). SUMMARY OF BACKGROUND DATA: Postoperative neurological deterioration is one of the most undesirable complications that can occur after surgery for DCM. METHODS: We analyzed data from the Canadian Spine Outcomes and Research Network DCM prospective cohort study. We defined postoperative neurological deterioration as any decrease in modified Japanese Orthopaedic Association (mJOA) score by at least one point from baseline to three months after surgery. Adverse events were collected using the Spinal Adverse Events Severity protocol. Secondary outcomes included patient-reported pain, disability, and health-related quality of life. RESULTS: Among a study cohort of 428 patients, 50 (12%) deteriorated by at least one mJOA point after surgery for DCM (21 by one point, 15 by two points, and 14 by three points or more). Significant risk factors included older age, female sex, and milder disease. Among those who deteriorated, 13 experienced contributing intraoperative or postoperative adverse events, six had alternative non-DCM diagnoses, and 31 did not have an identifiable reason for deterioration. Patients who deteriorated had significantly lower mJOA scores at one year after surgery [13.5 (SD 2.7) vs. 15.2 (SD 2.2), P <0.01 and those with larger deteriorations were less likely to recover their mJOA to at least their preoperative baseline, but most secondary measures of pain, disability, and health-related quality of life were unaffected. CONCLUSIONS: The incidence of deterioration of mJOA scores after surgery for DCM was approximately one in 10, but some deteriorations were unrelated to actual spinal cord impairment and most secondary outcomes were unaffected. These findings can inform patient and surgeon expectations during shared decision-making, and they demonstrate that the interpretation of mJOA scores without clinical context can sometimes be misleading.

Beneficial Effects of Preoperative Exercise on the Outcomes of Lumbar Fusion Spinal Surgery.

Purpose: To determine whether there was an association between self-reported preoperative exercise and postoperative outcomes after lumbar fusion spinal surgery. Method: We performed a retrospective multivariable analysis of the prospective Canadian Spine Outcomes and Research Network (CSORN) database of 2,203 patients who had elective single-level lumbar fusion spinal surgeries. We compared adverse events and hospital length of stay between patients who reported regular exercise (twice or more per week) prior to surgery ("Regular Exercise") to those exercising infrequently (once or less per week) ("Infrequent Exercise") or those who did no exercise ("No Exercise"). For all final analyses, we compared the Regular Exercise group to the combined Infrequent Exercise or No Exercise group. Results: After making adjustments for known confounding factors, we demonstrated that patients in the Regular Exercise group had fewer adverse events (adjusted odds ratio 0.72; 95% CI: 0.57, 0.91; p = 0.006) and significantly shorter lengths of stay (adjusted mean 2.2 vs. 2.5 d, p = 0.029) than the combined Infrequent Exercise or No Exercise group. Conclusions: Patients who exercised regularly twice or more per week prior to surgery had fewer postoperative adverse events and significantly shorter hospital lengths of stay compared to patients that exercised infrequently or did no exercise. Further study is required to determine effectiveness of a targeted prehabilitation programme.

Objectif : déterminer s'il y avait une association entre les exercices préopératoires autodéclarés et les résultats postopératoires après une chirurgie de fusion lombaire. Méthodologie : analyse multivariable rétrospective de la base de données prospective Canadian Spine Outcomes and Research Network (CSORN) composée de 2 203 patients qui avaient subi une chirurgie de fusion lombaire univertébrale non urgente. Les chercheurs ont comparé les événements indésirables et la durée du séjour hospitalier entre les patients qui déclaraient faire de l'exercice régulier (au moins deux fois par semaine) avant l'opération (« exercice régulier ¼) à ceux qui n'en faisaient pas souvent (une fois ou moins par semaine; « exercice peu fréquent ¼) et qui n'en faisaient pas du tout (« absence d'exercice ¼). Pour toutes les analyses définitives, ils ont comparé le groupe qui faisait de l'exercice régulier aux groupes combinés d'exercice peu fréquent et d'absence d'exercice. Résultats : après correction pour tenir compte des facteurs confusionnels connus, les chercheurs ont démontré que les patients du groupe faisant de l'exercice régulier présentaient moins d'événements indésirables (rapport de cotes rajusté 0,72; IC à 95 % : 0,57, 0,91; p = 0,006) et leur séjour à l'hôpital était significativement plus court (moyenne corrigée 2,2 jours par rapport à 2,5 jours, p = 0,029) que dans le groupe combiné d'exercice peu fréquent et d'absence d'exercice. Conclusions : les patients qui faisaient de l'exercice régulièrement au moins deux fois par semaine avant l'opération présentaient moins d'événements indésirables après l'opération et étaient hospitalisés beaucoup moins longtemps que ceux qui ne faisaient pas beaucoup d'exercice ou n'en faisaient pas du tout. Il faudra réaliser d'autres études pour déterminer l'efficacité d'un programme de préréadaptation ciblé.

Cost consequence analysis of waiting for lumbar disc herniation surgery.

The economic repercussions of waiting for lumbar disc surgery have not been well studied. The primary goal of this study was to perform a cost-consequence analysis of patients receiving early vs late surgery for symptomatic disc herniation from a societal perspective. Secondarily, we compared patient factors and patient-reported outcomes. This is a retrospective analysis of prospectively collected data from the CSORN registry. A cost-consequence analysis was performed where direct and indirect costs were compared, and different outcomes were listed separately. Comparisons were made on an observational cohort of patients receiving surgery less than 60 days after consent (short wait) or 60 days or more after consent (long wait). This study included 493 patients with surgery between January 2015 and October 2021 with 272 patients (55.2%) in the short wait group and 221 patients (44.8%) classified as long wait. There was no difference in proportions of patients who returned to work at 3 and 12-months. Time from surgery to return to work was similar between both groups (34.0 vs 34.9 days, p = 0.804). Time from consent to return to work was longer in the longer wait group corresponding to an additional $11,753.10 mean indirect cost per patient. The short wait group showed increased healthcare usage at 3 months with more emergency department visits (52.6% vs 25.0%, p < 0.032), more physiotherapy (84.6% vs 72.0%, p < 0.001) and more MRI (65.2% vs 41.4%, p < 0.043). This corresponded to an additional direct cost of $518.21 per patient. Secondarily, the short wait group had higher baseline NRS leg, ODI, and lower EQ5D and PCS. The long wait group had more patients with symptoms over 2 years duration (57.6% vs 34.1%, p < 0.001). A higher proportion of patients reached MCID in terms of NRS leg pain at 3-month follow up in the short wait group (84.0% vs 75.9%, p < 0.040). This cost-consequence analysis of an observational cohort showed decreased costs associated with early surgery of $11,234.89 per patient when compared to late surgery for lumbar disc herniation. The early surgery group had more severe symptoms with higher healthcare utilization. This is counterbalanced by the additional productivity loss in the long wait group, which likely have a more chronic disease. From a societal economic perspective, early surgery seems beneficial and should be promoted.

Determining minimal clinically important difference estimates following surgery for degenerative conditions of the lumbar spine: analysis of the Canadian Spine Outcomes and Research Network (CSORN) registry.

BACKGROUND CONTEXT: There is significant variability in minimal clinically important difference (MCID) criteria for lumbar spine surgery that suggests population and primary pathology specific thresholds may be required to help determine surgical success when using patient reported outcome measures (PROMs). PURPOSE: The purpose of this study was to estimate MCID thresholds for 3 commonly used PROMs after surgical intervention for each of 4 common lumbar spine pathologies. STUDY DESIGN/SETTING: Observational longitudinal study of patients from the Canadian Spine Outcomes and Research Network (CSORN) national registry. PATIENT SAMPLE: Patients undergoing surgery from 2015 to 2018 for lumbar spinal stenosis (LSS; n = 856), degenerative spondylolisthesis (DS; n = 591), disc herniation (DH; n = 520) or degenerative disc disease (DDD n = 185) were included. OUTCOME MEASURES: PROMs were collected presurgery and 1-year postsurgery: the Oswestry Disability Index (ODI), and back and leg Numeric Pain Rating Scales (NPRS). At 1-year, patients reported whether they were 'Much better'/'Better'/'Same'/'Worse'/'Much worse' compared to before their surgery. Responses to this item were used as the anchor in analyses to determine surgical MCIDs for benefit ('Much better'/'Better') and substantial benefit ('Much better'). METHODS: MCIDs for absolute and percentage change for each of the 3 PROMs were estimated using a receiving operating curve (ROC) approach, with maximization of Youden's index as primary criterion. Area under the curve (AUC) estimates, sensitivity, specificity and correct classification rates were determined. All analyses were conducted separately by pathology group. RESULTS: MCIDs for ODI change ranged from -10.0 (DDD) to -16.9 (DH) for benefit, and -13.8 (LSS) to -22.0 (DS,DH) for substantial benefit. MCID for back and leg NPRS change were -2 to -3 for each group for benefit and -4.0 for substantial benefit for all groups on back NPRS. MCID estimates for percentage change varied by PROM and pathology group, ranging from -11.1% (ODI for DDD) to -50.0% (leg NPRS for DH) for benefit and from -40.0% (ODI for DDD) to -66.6% (leg NPRS for DH) for substantial benefit. Correct classification rates for all MCID thresholds ranged from 71% to 89% and were relatively lower for absolute vs percent change for those with high or low presurgical scores. CONCLUSIONS: Our findings suggest that the use of generic MCID thresholds across pathologies in lumbar spine surgery is not recommended. For patients with relatively low or high presurgery PROM scores, MCIDs based on percentage change, rather than absolute change, appear generally preferable. These findings have applicability in clinical and research settings, and are important for future surgical prognostic work.

Patient, clinical, surgical, and institutional factors associated with length of stay in scheduled degenerative thoracolumbar spine surgery: National Multicenter Cohort Analysis from the Canadian Spine Outcomes and Research Network.

OBJECTIVE: Length of stay (LOS) is a contributor to costs and resource utilization. The primary goal of this study was to identify patient, clinical, surgical, and institutional variables that influence LOS after elective surgery for thoracolumbar degenerative pathology. The secondary objective was to examine variability in LOS and institutional strategies used to decrease LOS. METHODS: This is a retrospective study of prospectively collected data from a multicentric cohort enrolled in the Canadian Spine Outcomes and Research Network (CSORN) between January 2015 and October 2020 who underwent elective thoracolumbar surgery (discectomy [1 or 2 levels], laminectomy [1 or 2 levels], and posterior instrumented fusion [up to 5 levels]). Prolonged LOS was defined as LOS greater than the median. Logistic regression models were used to determine factors associated with prolonged LOS for each procedure. A survey was sent to the principal investigators of the participating healthcare institutions to understand institutional practices that are used to decrease LOS. RESULTS: A total of 3700 patients were included (967 discectomies, 1094 laminectomies, and 1639 fusions). The median LOSs for discectomy, laminectomy, and fusion were 0.0 (IQR 1.0), 1.0 (IQR 2.0), and 4.0 (IQR 2.0) days, respectively. On multivariable analysis, predictors of prolonged LOS for discectomy were having more leg pain, higher Oswestry Disability Index (ODI) scores, symptom duration more than 2 years, having undergone an open procedure, occurrence of an adverse event (AE), and treatment at an institution without protocols to reduce LOS (p < 0.05). Predictors of prolonged LOS for laminectomy were increased age, living alone, higher ODI scores, higher BMI, open procedures, longer operative time, AEs, and treatment at an institution without protocols to reduce LOS (p < 0.05). For posterior instrumented fusion, predictors of prolonged LOS were older age, living alone, more comorbidities, higher ODI scores, longer operative time, AEs, and treatment at an institution without protocols to reduce LOS (p < 0.05). The laminectomy group had the largest variability in LOS (SD 4.4 days, range 0-133 days). Three hundred fifty-four patients (22%) had an LOS above the 75th percentile. Ten institutions (53%) had either Enhanced Recovery After Surgery or standardized protocols in place. CONCLUSIONS: Among the factors identified in this study, worse baseline ODI scores, experiencing AEs, and treatment at an institution without protocols aimed at reducing LOS were predictive of prolonged LOS in all surgical groups. The laminectomy group had the largest variability in LOS.