Journal List > J Korean Soc Surg Hand > v.20(4) > 1106504

J Korean Soc Surg Hand. 2015 Dec;20(4):204-208. Korean.
Published online December 31, 2015.  https://doi.org/10.12790/jkssh.2015.20.4.204
Copyright © 2015. The Korean Society for Surgery of the Hand
Extensor Digiti Minimi Triggering Caused by an Anatomical Variation: A Case Report
Youn-Tae Roh,1 Changhoon Jeong,2 Soo-Hwan Kang,2 Jae-Young Lee,2 Sang-Hyun Jeon,2 and Il-Jung Park2
1Department of Orthopaedic Surgery, Uijeongbu Paik Hospital, Uijeongbu, Korea.
2Department of Orthopaedic Surgery, College of Medicine, The Catholic University of Korea, Seoul, Korea.

Correspondence to: Il-Jung Park. Department of Orthopaedic Surgery, Bucheon St. Mary's Hospital, College of Medicine, The Catholic University of Korea, 327 Sosa-ro, Wonmi-gu, Bucheon 14647, Korea. TEL: +82-32-340-7034, FAX: +82-32-340-2671, Email: jikocmc@naver.com
Received August 02, 2015; Accepted August 11, 2015.

This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.


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.

Keywords: Trigger finger; Extensor digiti minimi; Extensor tendon

Figures


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 metacarpal bone (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.
Click for larger image

References
1. Ambrose J, Goldstone R. Anomalous extensor digiti minimi proprius causing tunnel syndrome in the dorsal compartment. Report of a case. J Bone Joint Surg Am 1975;57:706–707.
2. Khazzam M, Patillo D, Gainor BJ. Extensor tendon triggering by impingement on the extensor retinaculum: a report of 5 cases. J Hand Surg Am 2008;33:1397–1400.
3. Panwar J, Thomas BP, Sreekanth R. Sonographic findings of extensor digiti minimi triggering caused by thickened extensor retinaculum. J Ultrasound 2015;18:79–82.
4. Park SE, Kim YY, Ji JH, Lee HH, Jeong JJ. Double triggering of extensor digiti minimi: a case report. Arch Orthop Trauma Surg 2013;133:429–432.
5. Park HS, Kim YH, Kim SS. Treatment of extensor digiti minimi triggering: two cases report. J Korean Soc Surg Hand 2010;15:44–46.
6. Wilson SM, Dubert T, Rozenblat M. Extensor tendon impingement in a gymnast. J Hand Surg Br 2006;31:66–67.
7. Rourke O, PJ;Sullivan O, T,M Stephens.Extensor tendon sheath stenosis resulting in triggering of the little finger. J Hand Surg Br 1994;19:662–663.
8. Durand S, Gaujoux G, Macquillan A. Triggering of the lateral slip of the extensor mechanism on a Bouchard's node. J Hand Surg Eur Vol 2011;36:340–341.
9. Tanaka T, Moran SL, Zhao C, Zobitz ME, An KN, Amadio PC. Anatomic variation of the 5th extensor tendon compartment and extensor digiti minimi tendon. Clin Anat 2007;20:677–682.
10. Yoo MJ, Chung KT, Kim JP, Kim MJ, Lee KJ. Tendon impingement of the extensor digiti minimi: clinical cases series and cadaveric study. Clin Anat 2012;25:755–761.