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.

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Swan Neck Deformity

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

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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.