Lumbar pannus presenting as cauda equina syndrome in a patient with longstanding rheumatoid arthritis.

Relatively little attention has been paid to lumbar spine involvement in rheumatoid arthritis (RA), and indeed it is generally considered to be an uncommon and usually clinically minor manifestation of the disease. We describe a case of acute right lower extremity weakness secondary to compression of multiple lumbar nerve roots by a large interforaminal rheumatoid pannus, and review the literature on this complication and other lumbar spine involvement in RA.