swan neck deformity

swan neck deformity

[swän]
Etymology: D, zwaan + AS, hnecca, neck; L, deformis, misshapen
1 also called zig-zag. an abnormal condition of the finger characterized by flexion of the distal interphalangeal joint and hyperextension of the proximal interphalangeal joint. It is caused by a taut profundus tendon in the presence of a weakened distal interphalangeal joint and may be combined with a volar plate rupture. The condition is seen most often in rheumatoid arthritis.
2 a structural abnormality of the kidney tubules associated with rickets. The kidney tubule connecting the glomerulus with the convoluted part of the tubule is narrowed into a configuration referred to as "swan neck." There are also a thinning and atrophy of the distal tubule and a shortening of the convoluted part.
Neurology A descriptor for a thin curved neck, resulting from muscular atrophy characteristic of myotonia dystrophica, often accompanied by ‘myopathic facies’—see 'Hatchet' face—myotonia, dysphagia, frontal baldness, testicular atrophy, cataracts; a variant of gracile swan neck is described in Modigliani syndrome
Pathology-kidney A descriptive term for the shortened and attenuated initial segment of a dissected proximal convoluted renal tubule seen by light microscopy in patients with De Toni-Fanconi syndrome
Rheumatology A descriptive term for the hyperextended proximal interphalangeal joint and compensatory flexion of the distal interphalangeal joints caused by shortening of the extensor tendon, classically seen in rheumatoid arthritis, but also in systemic lupus erythematosus, Jaccoud’s—post-rheumatic fever—arthritis, psoriatic arthritis, scleroderma, camptodactyly

swan neck deformity

Rheumatology A descriptor for the hyperextended proximal interphalangeal joint and compensatory flexion of the distal interphalangeal joints caused by shortening of the extensor tendon, classically seen in rheumatoid arthritis, but also in SLE, post-rheumatic fever arthritis, psoriatic arthritis, scleroderma, camptodactyly. Cf Boutonniere deformity.
References in periodicals archive ?
Most common deformities are buttonhole deformity, swan neck deformity, and ulnar deviation of the metacarpophalangeal joints.
Greater deformity was observed in the right hand than left hand in our study with regard to piano key sign and boutonniere deformity, and no differences were detected concerning swan neck deformity, ulnar deviation, Z deformity, tenosynovitis, interosseous atrophy, or hypertrophic degeneration.
21) When evaluated separately, the buttonhole deformity has been reported in 36% of RA patients and swan neck deformity in 14%.