Impact of Ankylosing Spondylitis/Diffuse Idiopathic Skeletal Hyperostosis on Postoperative and Patient-Reported Outcomes Following Elective Cervical and Lumbar Surgery
Research Fellow Rothman Orthopaedic Institute Rothman Orthopaedic Institute
Disclosure(s):
Joydeep Baidya, BS: No financial relationships to disclose
Introduction: Ankylosing spondylitis (AS) is the most common form of spondyloarthritis and manifests in inflammatory back pain and excess bone formation in the spine. Diffuse idiopathic skeletal hyperostosis (DISH) is a noninflammatory condition that is characterized by contiguous ossification of 4 or more vertebral bodies and can present similarly to AS. The goal of this study is to address a gap in the literature regarding surgical and patient-reported outcomes after elective cervical and lumbar surgery amongst patients with these conditions.
Methods: Adult patients with AS or DISH undergoing elective spine surgery at a tertiary care center were retrospectively identified (2004-2023). Patients were 3:1 propensity score matched to a control cohort of patients without AS/DISH undergoing similar procedures. Demographics, surgical variables, and outcomes were collected.
Results: 66 patients with AS/DISH met inclusion criteria—42 cervical (25 ACDF, 17 PCDF) and 24 lumbar (17 PLDF, 7 TLIF). In the cervical cohort, CCI was greater in the AS/DISH group (3.021.65 vs. 1.922.07, p< 0.001). Patients with AS/DISH experienced higher rates of 0-30 day readmission in both cohorts (Cervical: 9.52% vs. 1.59%, p=0.035; Lumbar: 20.8% vs. 2.78%, p=0.010). In the cervical cohort, AS/DISH patients experienced higher rates of 31-90 day readmission (7.14% vs. 0.79%, p=0.049) while in the lumbar cohort, a greater proportion of them were discharged to skilled nursing facilities (19.0% vs. 4.55%, p=0.002). Patients in neither cohort experienced differences in 1-year reoperation or revision. In the cervical cohort, 1-year VAS Neck and VAS Arm; 2-year VAS Arm; 3-month, 1-year, and 2-year mJOA; and 1-year and 2-year MCS were better for AS/DISH. In the lumbar cohort, delta 6-month VAS Back was better while preoperative and 6-month VAS Back; delta 6-month and 1-year VAS Leg; and delta 6-month and 2-year MCS were worse for AS/DISH patients (all p< 0.05).
Conclusion : AS/DISH is associated with short-term readmissions after elective cervical and lumbar surgeries. Although there were differences in several postoperative PROMs between AS/DISH and control patients, the change from baseline was generally similar. Surgeons should attempt to avoid readmissions and optimize outcomes for AS/DISH patients via early postoperative mobilization, pain expectation counseling and proactive multimodal pain control, and proper DMARD management.