Establishing mild, moderate and severe criteria for the myelopathy disability index in cervical spondylotic myelopathy

Degenerative cervical myelopathy: establishing severity thresholds for neuromotor dysfunction in the aging spine using the NIH Toolbox Assessment Scale

Degenerative cervical myelopathy (DCM) is a leading cause of age-related non-traumatic spinal cord disorders resulting from chronic degeneration of the cervical spine. While traditional clinical assessments rely on patient-reported measures, this study used the NIH Toolbox Motor Battery (NIHTBm) as an objective, quantitative measure to determine DCM severity. The objective is to define NIHTBm cutoff values that can accurately classify the severity of DCM neuromotor dysfunction. A case-controlled pilot study of patients with DCM and age-matched controls. The focus was an in-depth quantitative motor assessment using the NIHTBm to understand the severity of neuromotor deficits due to degenerative spine disease. Motor assessments, dexterity, grip strength, balance, and gait speed were measured in 45 DCM patients and 37 age-matched healthy subjects (HC). Receiver operating curve (ROC) analysis determined cutoff values for mild and moderate-to-severe myelopathy which were validated by comparing motor assessment scores with disability scores. The ROC curves identified thresholds for mild dexterity impairment (T-score range 38.4 - 33.5, AUC 0.77), moderate-to-severe dexterity impairment (< 33.5, AUC 0.70), mild grip strength impairment (47.4 - 32.0, AUC 0.80), moderate-to-severe grip strength impairment (< 32.0, AUC 0.75), mild balance impairment (36.4 - 33.0, AUC 0.61), and moderate-to-severe balance impairment (< 33.0, AUC 0.78). Mild gait speed impairment was defined as 0.78-0.6 m/sec (AUC 0.65), while moderate-to-severe gait speed impairment was < 0.6 m/sec (AUC 0.65). The NIHTB motor score cutoff points correlated negatively with the DCM neck disability index (NDI) and showed balance and dexterity measures as independent indicators of DCM dysfunction. The use of NIHTB allows for precise delineation of DCM severity by establishing cutoff values corresponding to mild and moderate-to-severe myelopathy. The use of NIHTB in DCM allows enhanced clinical precision, enabling clinicians to better pinpoint specific motor deficits in DCM and other neurological disorders with motor deficits, including stroke and traumatic brain injury (TBI). Furthermore, the utility of objective assessment, NIHTB, allows us to gain a better understanding of the heterogeneity of DCM, which will enhance treatment strategies. This study serves as a foundation for future research to facilitate the discovery of innovative treatment strategies for DCM and other neurological conditions.

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.

Life expectancy in patients with degenerative cervical myelopathy is currently reduced but can be restored with timely treatment

PURPOSE

Degenerative cervical myelopathy is a progressive slow-motion spinal cord injury. Surgery is the mainstay of treatment. Baseline disability predicts surgical recovery; therefore, timely treatment is critical to restoring function. However, current challenges mean most patients present with advanced disease and are instead left with life changing disabilities. While short-term mortality is rarely reported, the long-term effects of this on life expectancy are unknown, including whether function could be modifiable with timely treatment. This article investigates the effect of DCM on life expectancy.

METHODS

The survival of patients from an observational study of patients undergoing surgery from 1994 to 2007 was compared to their expected survival using a gender- and aged -matched cohort. Comparisons were made by one sample log-rank test and standardised mortality ratios. Factors associated with survival were explored using a Cox regression analysis, including disease severity.

RESULTS

A total of 357 patients were included in the analysis. After a median follow-up of 15.3 years, 135 of 349 patients had died; 114.7 deaths would have been expected. The DCM cohort had an increased risk of death compared to the non-DCM cohort (standardised mortality ratio 1.18 [95% CI: 1.02-1.34]. Age at operation 1.08 (95% CI: 1.07 to 1.1, p < 0.001) and severe DCM 1.6 (95% CI: 1.06 to 2.3, p = 0.02) were associated with worse survival (N = 287). In those surviving at least 2 years after surgery, only severe DCM was associated with conditional survival (HR 1.6, 95% CI 1.04 2.4, p = 0.03).

CONCLUSION

Life expectancy is reduced in those undergoing surgery for DCM. This is driven by premature mortality among those left with severe disability. As disability can be reduced with timely treatment, these findings reinforce the need for collective and global action to raise awareness of DCM and enable early diagnosis.

Myelopathy disability index: establishing criteria for mild, moderate and severe impairment in patients with degenerative cervical myelopathy

PURPOSE

To find the cut-off values in the Myelopathy Disability Index (MDI) that will allow us to classify the severity of Degenerative Cervical Myelopathy (DCM) into mild, moderate and severe.

METHODS

Cross-sectional study with prospective data collection, with a total of 64 patients diagnosed with Degenerative Cervical Myelopathy (DCM). Anthropometric, diagnostic, neurological, functional and quality of life variables were collected. A Receiver Operating Curve (ROC) was performed. The cut-off points were validated by comparing the functional status of patients in the 3 groups and their Nurick scores.

RESULTS

Sixty-four patients (23 women) with a mean age of 61.97 (SD 11.57) participated in this study. The majority of patients were Nurick I (28.13%) and Nurick II (32.81%). The medium MDI was 7.36 (SD 6.66) and the mJOA was 14.08 (SD 2.57). The mild-moderate cut-off value was between 4 and 5, with an Area Under the Curve (AUC) of 0.805, sensitivity of 0.853 and specificity of 0.6. For moderate-severe, the cut-off value obtained was between 7 and 8, with an AUC of 0.862, sensitivity of 0.857 and specificity of 0.684. Patients with greater severity had significantly lower functionality, with a P-value of 0.004 in the 30 Metre Walking Test and 0.005 in the Nine-Hole Peg Test. Established severity groups were also significantly related to the different categories of the Nurick score (P-value = 0.000).

CONCLUSION

MDI values between 0 and 4 correspond to mild DCM, between 5 and 7 would be moderate DCM and from 8 to 30 indicate severe DCM.

Comparison of health-related quality of life in patients with traumatic brain injury, subarachnoid haemorrhage and cervical spine disease

PURPOSE

The degree of disability that is acceptable to patients following traumatic brain injury (TBI) continues to be debated. While the dichotomization of outcome on the Glasgow Outcome Score (GOSE) into 'favourable' and 'unfavourable' continues to guide clinical decisions, this may not reflect an individual's subjective experience. The aim of this study is to assess how patients' self-reported quality of life (QoL) relates to objective outcome assessments and how it compares to other debilitating neurosurgical pathologies, including subarachnoid haemorrhage (SAH) and cervical myelopathy.

METHOD

A retrospective analysis of over 1300 patients seen in Addenbrooke's Hospital, Cambridge, UK with TBI, SAH and patients pre- and post- cervical surgery was performed. QoL was assessed using the SF-36 questionnaire. Kruskal-Wallis test was used to analyse the difference in SF-36 domain scores between the four unpaired patient groups. To determine how the point of dichotomization of GOSE into 'favourable' and 'unfavourable' outcome affected QOL, SF-36 scores were compared between GOSE and mRS.

RESULTS

There was a statistically significant difference in the median Physical Component Score (PCS) and Mental Component Score (MCS) of SF-36 between the three neurosurgical pathologies. Patients with TBI and SAH scored higher on most SF-36 domains when compared with cervical myelopathy patients in the severe category. While patients with Upper Severe Disability on GOSE showed significantly higher PC and MC scores compared to GOSE 3, there was a significant degree of variability in individual responses across the groups.

CONCLUSION

A significant number of patients following TBI and SAH have better self-reported QOL than cervical spine patients and patients' subjective perception and expectations following injury do not always correspond to objective disability. These results can guide discussion of treatment and outcomes with patients and families.

Clinical Efficacy and Safety of Anterior Cervical Decompression versus Segmental Fusion and Posterior Expansive Canal Plasty in the Treatment of Multilevel Cervical Spondylotic Myelopathy

Objective

To compare the clinical efficacy and safety of anterior cervical decompression and segmental fusion and posterior expansive canal plasty in the treatment of multisegment cervical myelopathy.

Methods

Retrospective analysis was performed of 56 cases of multisegment cervical myelopathy patients admitted from July 2018 to June 2021, 32 male patients and 24 females, aged 56.9 ± 12.8 years with an average duration of 10.6 ± 3.2 years. All patients' preoperative imaging examination revealed multiple-segmented cervical disc herniation and had clinical manifestations of cervical myelopathy.

Results

No neurovascular complications occurred in both groups, and 24 to 36 months of follow-up (mean 28.6 months) were obtained. The height of the cervical spondylosis segment was higher than that 2 weeks after surgery (p < 0.05), and the curvature of the cervical spine was significantly lower than that before surgery. There was no statistical significance in the height of the anterior column and curvature of the cervical vertebra at 2 weeks after surgery and at the last follow-up (p > 0.05). There were statistically significant differences in anterior curvature of the cervical spine between the two groups at 2 weeks after surgery and the last follow-up (p < 0.05). Japanese Orthopaedic Association (JOA) scores in both groups recovered significantly after surgery. At 3 months and the last follow-up, the improvement rate of JOA score in the anterior approach group was significantly higher than that in the posterior approach group (p < 0.05), and the improvement rate of JOA score in the anterior approach group was also better than that in the posterior approach group (p < 0.05).

Conclusion

This segmented anterior fusion procedure can effectively restore the anterior cervical column height and can significantly improve spinal cord function compared with posterior spinal canal enlargement plasty, thus could be considered an effective option for the treatment of multisegment cervical myelopathy.