Occipitocervical Fusion Has Potential to Improve Sleep Apnea in Patients With Rheumatoid Arthritis and Upper Cervical Lesions

In Brief Study Design. Case series. Objective. To analyze factors that contribute to the development of sleep apnea in patients with rheumatoid arthritis (RA) and upper cervical lesions. Summary of Background Data. No large prospective study has analyzed the association between sleep apnea and upper cervical involvement resulting from RA. Furthermore, only 1 report in the literature describes a case of sleep apnea accompanying rheumatoid vertical subluxation of the odontoid process. Methods. The authors analyzed 8 consecutive RA patients with upper cervical lesions who underwent occipitocervical (O-C) fusion. The patients were examined with all-night polysomnography before and after surgery. Patients with apnea-hypopnea index values ≥5 were diagnosed to have sleep apnea. O-C2 angles were calculated from cervical radiographs. Results. All 8 patients were diagnosed as having sleep apnea, and most of their apneic episodes were obstructive in origin. Among the 4 patients with medullary compression, central apneic episodes comprised ≤5% of their respiratory events. Two patients with severe sleep apnea had negative O-C2 angles. Six patients who showed postoperative improvements in their sleep apnea all had positive changes in their O-C2 angles exceeding 5° after surgery. The differences between preoperative and postoperative O-C2 angles were significantly greater in the patients with improvement of sleep apnea than in the patients with worsening sleep apnea. Conclusion. All our study patients with RA and upper cervical lesions had obstructive-dominant sleep apnea. Negative O-C2 angles may result in upper airway narrowing, increasing the severity of sleep apnea. O-C fusion with correction of kyphosis at the craniovertebral junction has the potential to improve sleep apnea in RA patients. All 8 study patients with rheumatoid arthritis and upper cervical lesions had obstructive-dominant sleep apnea. O-C2 angle has a major impact on the development of obstructive sleep apnea. O-C fusion with correction of kyphosis at the craniovertebral junction has the potential to improve this disorder.