J Korean Soc Surg Hand.  2015 Dec;20(4):204-208. 10.12790/jkssh.2015.20.4.204.

Extensor Digiti Minimi Triggering Caused by an Anatomical Variation: A Case Report

• Roh YT
• Jeong C
• Kang SH
• Lee JY
• Jeon SH
• Park IJ

• KMID: 2150404
• DOI: http://doi.org/10.12790/jkssh.2015.20.4.204

Abstract

Although flexor tendon triggering due to stenosing flexor tenosynovitis is common clinically, extensor triggering is quite rare. Known common causes are impingement between extensor tendon and extensor retinaculum, stenosis of the tendon sheath, and impingement between extensor tendon and osteophyte. We report rare case of triggering in the little finger caused by impingement between extensor digiti minimi and synovial septum.

Keyword

Trigger finger; Extensor digiti minimi; Extensor tendon

MeSH Terms

Constriction, Pathologic
Fingers
Osteophyte
Tendons
Tenosynovitis

Figure

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  Fig. 1. A 22-year-old male student presented a mass and triggering according to the motion of the finger which were palpated on the base of fifth metacarpal bone (black asterisk).

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  Fig. 2. In real time ultrasonography, extensor digiti minimi (white arrow) was observed as a single tendon at the base of fifth metacarpalbone (A), but it was divided into two slips as it progressed distally (B).

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  Fig. 3. Intra-operative photographs. (A) Duplicated EDM originated distal to the retinaculum. (B, C) Synovial septum (black arrowhead) was present between the radial and ulnar EDM slip. (D) Bifurcated area of EDM tendon (black arrow) was more thickened than surrounding tendon. (E) When the little finger was flexed, impingement between bifurcated area and synovial septum resulted in tightening of the ulnar side EDM slip, with laxity of the radial slip. (F) Two EDM slips were sutured after excision of synovial septum, and then triggering was disappeared. EDM, extensor digiti minimi.

Reference

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