Swan neck deformity

Swan neck deformity
	Swan neck deformity in a 65-year-old rheumatoid arthritis patient.
Specialty	Orthopedic

Swan neck deformity is a deformed position of the finger, in which the joint closest to the fingertip is permanently bent toward the palm while the nearest joint to the palm is bent away from it (DIP flexion with PIP hyperextension). It is commonly caused by injury or inflammatory conditions like rheumatoid arthritis or sometimes familial (congenital, like Ehlers–Danlos syndrome[1]).

Pathophysiology

Swan neck deformity has many of possible causes arising from the DIP, PIP, or even the MCP joints. In all cases, there is a stretching of the volar plate at the PIP joint to allow hyperextension, plus some damage to the attachment of the extensor tendon to the base of the distal phalanx that produces a hyperflexed mallet finger. Duck bill deformity is a similar condition affecting the thumb (which cannot have true swan neck deformity because it does not have enough joints).

Diagnosis

Mainly clinically. MRI of the hand may suggest volar plate attenuation of PIP and extensor tendon damage for DIP

Treatment

Splinting for fingers. Passive stretching and clearing the deformity.

References

ERÇÖÇEN, A. R.; et al. "Dynamic Swan Neck Deformity in a Patient with Ehlers–Danlos Syndrome". The Journal of Hand Surgery. Retrieved 23 May 2013.

External links

Swan neck deformity at Wheeless' Textbook of Orthopedics, a technical review of the condition
Rheumatoid arthritis: Image showing deformities

This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.

[1] ERÇÖÇEN, A. R.; et al. "Dynamic Swan Neck Deformity in a Patient with Ehlers–Danlos Syndrome". The Journal of Hand Surgery. Retrieved 23 May 2013.