General assessment of age, inflammation, atrophy, deformity, and asymmetry. Age-related changes include prominent veins on the dorsum of the hand, mild atrophy of the intrinsic muscles, lentigines on the skin and osteoarthritic prominences at the CMC joint at the base of the thumb, and osteophytes at the DIP and PIP joints.
Acute inflammation following trauma is characterized by regional swelling and erythema. Chronic inflammation is often associated with synovitis of the joints and/or tendons.
Assessing the deformity, motion, and instability of each digit requires a systematic approach and thorough documentation. Detailed wrist palpation, including provocative testing for carpal instability, will allow the examiner to localize specific disorders.
Rheumatoid Arthritis (RA):
Can result in deformity of any or all of the joints of the hand and wrist (e.g. Boutonnière’s deformity, swan-neck deformity , Z-shaped deformity of the thumb)
Juvenile Rheumatoid Arthritis (JRA):
Children with inflammatory arthritis develop growth retardation of the metacarpals leading to shortening of one or several digits. Inflammation at the wrist results in lost range of motion.
Telescoped shortening of the digits, produced by partial resorption of the phalanges, often associated with concentric wrinkling of the skin (opera-glass hand), and psoriatic lesions of the skin or nails. Fused IP joints are also common.
The aponeurotic thickening of the palmar fascia may extend distally to involve the digits. The fingers become flexed at the MCP joints by taut fibrous bands, or “cords,” that radiate from the palmar fascia, and the hand cannot be placed flat on a table (positive tabletop test)
Mallet finger is a flexed DIP joint with no active extension due to an acute or chronic rupture of the terminal tendon of the extensor mechanism. A dropped knuckle refers to fracture of the metacarpal shaft proximal to the MCP joint, with disappearance of the prominence of the metacarpal head typically involving the fifth metacarpal “boxer’s fracture.”
Osteophytes at the DIP and PIP joints (Heberden and Bouchard nodes respectively) occur with age or following trauma and may be associated with gradual ulnar drift of the fingers. “Squaring” of the carpometacarpal (CMC) joint at the base of the thumb due to OA is particularly common.
Other Deformity Patterns