This 60-year-old man has had rheumatoid arthritis (RA) for 40 years. Typical of progressive, long-standing disease is the deformity seen here in his hands and feet.
The initial manifestation of RA, which may occur in any joint, is stiffness that is worse on awakening and better with activity.
Synovitis is characterized by pain, warmth, erythema, synovial thickening, effusion, and capsular distention within the joint. Persistent synovitis causes weakening of the periarticular supporting structure and malfunction and wasting of muscles acting on the affected joint. Postinflammatory contracture results in fixed deformity of the joint.
Hand deformity in RA involves the proximal interphalangeal (PIP) and metacarpophalangeal joints, and hyperextension of the distal interphalangeal (DIP) joint is extremely common. Joint deformities include ulnar drift of the fingers, swan-neck deformity, boutonnière deformity, volar subluxation, and ulnar deviation.
Foot deformities include hammer toe, hallux rigidus, cocked-up toes, and fixation of the metatarsophalangeal joint in dorsiflexion, with the PIP joint in plantar flexion and the DIP joint freely moving. Tenderness and swelling of the metatarsophalangeal joint are early manifestations of RA. Fibular deviation of the toes may occur at a later stage. There is no sensory loss. The lower limbs are most commonly affected in patients with vasculitis. This type of neuropathy may be sensory, with stocking-type anesthesia, or it may be of a mixed sensorimotor type with foot drop.