An observational study of patient-rated outcome after atlantoaxial fusion in patients with rheumatoid arthritis and osteoarthritis.

Background: Fusion is used to address several types of abnormality of the atlantoaxial segment. Traditionally, outcome has been assessed by achieving solid bony union. Recently, however, patient-rated outcome instruments have been increasingly used, although these may be influenced by concomitant comorbidity.
Questions/purposes: We therefore asked whether patients with rheumatoid arthritis (RA), with its associated comorbidity, had worse self-rated outcomes after C1-2 fusion than patients with osteoarthritis (OA).
Patients and Methods: We retrospectively reviewed all 30 (23 OA and seven RA) prospectively followed patients in our local Spine Registry (part of the Spine Society of Europe Spine Tango Registry) who had undergone C1-2 fusion. Before surgery and 3 and 12 months later, patients completed the multidimensional Core Outcome Measures Index (COMI) questionnaire. Global outcome and satisfaction with treatment were also assessed.
Results: We found no group differences for duration of operation, blood loss, or perioperative surgical or general complications. Compared with the OA group, the RA group showed a better baseline COMI score and less improvement in the COMI from preoperatively to 12 months followup. However, the proportion of "good" global scores at 12 months followup was similarly high in both groups (87% OA and 86% RA) as was satisfaction (96% for OA versus 86% for RA).
Conclusions: Symptoms and impairment were less severe in the RA group at baseline and showed less improvement after surgery, but the proportion of "good global outcomes" was similar in both groups, and the great majority of patients in both groups were satisfied with their treatment.
Level of Evidence: Level III, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.