What is the pathophysiology of cervical myelopathy in rheumatoid arthritis?

What is the pathophysiology of cervical myelopathy in rheumatoid arthritis?

• A. Spinal ligament laxity → brainstem and/or spinal cord compression
• B. Vascular occlusion of the carotid arteries
• C. Lumbar disc degeneration
• D. Peripheral neuropathy of the upper limbs

Answer: (A)

In rheumatoid arthritis, the cervical spine can be attacked by inflammatory damage that weakens the supporting ligaments and erodes bony structures around the craniovertebral junction. The most pivotal change is laxity of the transverse ligament of the atlas, which allows increased movement between the first and second cervical vertebrae (atlantoaxial instability). This instability, often accompanied by pannus formation and odontoid erosion, narrows the spinal canal and compresses the spinal cord or brainstem. The result is cervical myelopathy from mechanical compression rather than a peripheral nerve problem or vascular event. The other options don’t fit this pattern: carotid vessel blockage would cause a stroke, lumbar disc degeneration occurs in the lower spine, and peripheral neuropathy involves nerves rather than direct spinal cord compression.

In rheumatoid arthritis, the cervical spine can be attacked by inflammatory damage that weakens the supporting ligaments and erodes bony structures around the craniovertebral junction. The most pivotal change is laxity of the transverse ligament of the atlas, which allows increased movement between the first and second cervical vertebrae (atlantoaxial instability). This instability, often accompanied by pannus formation and odontoid erosion, narrows the spinal canal and compresses the spinal cord or brainstem. The result is cervical myelopathy from mechanical compression rather than a peripheral nerve problem or vascular event. The other options don’t fit this pattern: carotid vessel blockage would cause a stroke, lumbar disc degeneration occurs in the lower spine, and peripheral neuropathy involves nerves rather than direct spinal cord compression.