Patient Characteristics Associated With Worsening of Neck Pain-Related Disability After Surgery for Degenerative Cervical Myelopathy: A Nationwide Study of 1508 Patients.

BACKGROUND AND OBJECTIVES: Functional status, pain, and quality of life usually improve after surgery for degenerative cervical myelopathy (DCM), but a subset of patients report worsening. The objective was to define cutoff values for worsening on the Neck Disability Index (NDI) and identify prognostic factors associated with worsening of pain-related disability 12 months after DCM surgery. METHODS: In this prognostic study based on prospectively collected data from the Norwegian Registry for Spine Surgery, the NDI was the primary outcome. Receiver operating characteristics curve analyses were used to obtain cutoff values, using the global perceived effect scale as an external anchor. Univariable and multivariable analyses were performed using mixed logistic regression to evaluate the relationship between potential prognostic factors and the NDI. RESULTS: Among the 1508 patients undergoing surgery for myelopathy, 1248 (82.7%) were followed for either 3 or 12 months. Of these, 317 (25.4%) were classified to belong to the worsening group according to the mean NDI percentage change cutoff of 3.3. Multivariable analyses showed that smoking (odds ratio [OR] 3.4: 95% CI 1.2-9.5: P < .001), low educational level (OR 2.5: 95% CI 1.0-6.5: P < .001), and American Society of Anesthesiologists grade >II (OR 2.2: 95% CI 0.7-5.6: P = .004) were associated with worsening. Patients with more severe neck pain (OR 0.8: 95% CI 0.7-1.0: P = .003) and arm pain (OR 0.8: 95% CI 0.7-1.0; P = .007) at baseline were less likely to report worsening. CONCLUSION: We defined a cutoff value of 3.3 for worsening after DCM surgery using the mean NDI percentage change. The independent prognostic factors associated with worsening of pain-related disability were smoking, low educational level, and American Society of Anesthesiologists grade >II. Patients with more severe neck and arm pain at baseline were less likely to report worsening at 12 months.

Long-Term Results After Surgery for Degenerative Cervical Myelopathy.

BACKGROUND AND OBJECTIVES: Degenerative cervical myelopathy (DCM) is a frequent cause of spinal cord dysfunction, and surgical treatment is considered safe and effective. Long-term results after surgery are limited. This study investigated long-term clinical outcomes through data from the Norwegian registry for spine surgery. METHODS: Patients operated at the university hospitals serving Central and Northern Norway were approached for long-term follow-up after 3 to 8 years. The primary outcome was change in the Neck Disability Index, and the secondary outcomes were changes in the European Myelopathy Scale score, quality of life (EuroQoL EQ-5D); numeric rating scales (NRS) for headache, neck pain, and arm pain; and perceived benefit of surgery assessed by the Global Perceived Effect scale from 1 year to long-term follow-up. RESULTS: We included 144 patients operated between January 2013 and June 2018. In total, 123 participants (85.4%) provided patient-reported outcome measures (PROMs) at long-term follow-up. There was no significant change in PROMs from 1 year to long-term follow-up, including Neck Disability Index (mean 1.0, 95% CI -2.1-4.1, P = .53), European Myelopathy Scale score (mean -0.3, 95% CI -0.7-0.1, P = .09), EQ-5D index score (mean -0.02, 95% CI -0.09-0.05, P = .51), NRS neck pain (mean 0.3 95% CI -0.2-0.9, P = .22), NRS arm pain (mean -0.1, 95% CI -0.8-0.5, P = .70), and NRS headache (mean 0.4, 95% CI -0.1-0.9, P = .11). According to Global Perceived Effect assessments, 106/121 patients (87.6%) reported to be stable or improved ("complete recovery," "much better," "slightly better," or "unchanged") at long-term follow-up compared with 88.1% at 1 year. Dichotomizing the outcome data based on severity of DCM did not demonstrate significant changes either. CONCLUSION: Long-term follow-up of patients undergoing surgery for DCM demonstrates persistence of statistically significant and clinically meaningful improvement across a wide range of PROMs.

Surgery for Degenerative Cervical Myelopathy: A Nationwide Registry-Based Observational Study With Patient-Reported Outcomes.

BACKGROUND: Indications and optimal timing for surgical treatment of degenerative cervical myelopathy (DCM) remain unclear, and data from daily clinical practice are warranted. OBJECTIVE: To investigate clinical outcomes following decompressive surgery for DCM. METHODS: Data were obtained from the Norwegian Registry for Spine Surgery. The primary outcome was change in the neck disability index (NDI) 1 yr after surgery. Secondary endpoints were the European myelopathy score (EMS), quality of life (EuroQoL 5D [EQ-5D]), numeric rating scales (NRS) for headache, neck pain, and arm pain, complications, and perceived benefit of surgery assessed by the Global Perceived Effect (GPE) scale. RESULTS: We included 905 patients operated between January 2012 and June 2018. There were significant improvements in all patient-reported outcome measures (PROMs) including NDI (mean -10.0, 95% CI -11.5 to -8.4, P < .001), EMS (mean 1.0, 95% CI 0.8-1.1, P < .001), EQ-5D index score (mean 0.16, 95% CI 0.13-0.19, P < .001), EQ-5D visual analogue scale (mean 13.8, 95% CI 11.7-15.9, P < .001), headache NRS (mean -1.1, 95% CI -1.4 to -0.8, P < .001), neck pain NRS (mean -1.8, 95% CI -2.0 to -1.5, P < .001), and arm pain NRS (mean -1.7, 95% CI -1.9 to -1.4, P < .001). According to GPE scale assessments, 229/513 patients (44.6%) experienced "complete recovery" or felt "much better" at 1 yr. There were significant improvements in all PROMs for both mild and moderate-to-severe DCM. A total of 251 patients (27.7%) experienced adverse effects within 3 mo. CONCLUSION: Surgery for DCM is associated with significant and clinically meaningful improvement across a wide range of PROMs.