The high incidence of subluxation in patients with rheumatoid arthritis (RA; up to 44%) necessitates thorough preoperative evaluation,1 especially when cervical spine manipulation may occur (as during laryngoscopy). Acute subluxation can cause quadriplegia or sudden death.
An 89-yr-old female with long-standing RA, and pain and paresthesias in both arms with cervical spine extension, presented for laparoscopic inguinal herniorraphy. Previously obtained magnetic resonance images demonstrated significant odontoid extension above McRae’s line (dotted line in fig.) and compression of the medulla (Med) cephalad to the spinomedullary junction. McRae’s line demarcates the foramen magnum orifice and extends from the tip of the clivus anteriorly to the occiput posteriorly; the odontoid normally lies caudad to McRae’s line.2 An awake, fiber-optic–assisted tracheal intubation was performed.
Atraumatic structural disruption of the craniovertebral junction includes basilar invagination (odontoid prolapse into the foramen magnum), basilar impression (acquired basilar invagination resulting from osteomalacia), and cranial settling (basilar invagination associated with RA).2 Complications of RA include brainstem compression secondary to atlantoaxial (C1 to C2) subluxation.3 Cervical myelopathy can mimic other rheumatoid complications (e.g., neuropathy, arthralgia, disuse muscle atrophy)1 ; consequently, the extent of subluxation may be underappreciated.
The need for preoperative imaging in RA patients lacks consensus (see table 8 in reference 1), but as symptoms and severity of subluxation do not necessarily correlate and asymptomatic subluxation is common, dynamic view radiographs, computerized tomographic images, or magnetic resonance images may be required to accurately assess atlantoaxial subluxation1,2 ; coupled with history and physical examinations, these studies should enable all anesthesiologists to safely care for patients with RA.
Competing Interests
The authors declare no competing interests.