Surgery for degenerative cervical myelopathy in patients with rheumatoid arthritis and ankylosing spondylitis: a nationwide registry-based study with patient-reported outcomes

PURPOSE: To compare patient-reported outcomes (PROMs) following surgery for degenerative cervical myelopathy (DCM) among patients with rheumatoid arthritis (RA) or ankylosing spondylitis (AS) versus those without rheumatic diseases. METHODS: Data were obtained from the Norwegian Registry for Spine Surgery. The primary outcome was change in the Neck Disability Index (NDI) at 1 year. Secondary endpoints included the European Myelopathy Score (EMS), quality of life (EuroQoL-5D [EQ-5D]), numeric rating scales (NRS) for headache, neck pain, and arm pain, and complications. RESULTS: Among 905 participants operated between 2012 and 2018, 35 had RA or AS. There were significant improvements in all PROMs at 1 year and no statistically significant difference between the cohorts in mean change in NDI (− 0.64, 95% CI − 8.1 to 6.8, P = .372), EQ-5D (0.10, 95% CI − 0.04 to 0.24, P = .168), NRS neck pain (− 0.8, 95% CI − 2.0 to 0.4, P = .210), NRS arm pain (− 0.6, 95% CI − 1.9 to 0.7, P = .351), and NRS headache (− 0.5, 95% CI − 1.7 to 0.8, P = .460). DISCUSSION AND CONCLUSION: Our study adds to the limited available evidence that surgical treatment cannot only arrest further progression of myelopathy but also improve functional status, neurological outcomes, and quality of life in patients with rheumatic disease.