Double tendons at the distal attachment of the extensor hallucis longus muscle

Abstract

The distal attachments of the extensor hallucis longus (EHL) tendons in 47 amputated legs and in eight cadavers were examined. The EHL had two tendons in 34 of the amputated legs and bilaterally in five cadavers. The lateral tendon was inserted to the middle of the dorsal aspect of the base of the distal phalanx of the hallux and the medial tendon to the medial side of the insertion of the lateral tendon. The length and thickness of these two tendons were measured and compared in order to obtain data for using these tendons in tendon repair and hallux varus corrections by autogenous tendon transfer surgery. Additionally, on the right foot of one of the cadavers, it was observed that the extensor hallucis brevis tendon united with the lateral tendon of the EHL. We recommend that foot-ankle surgeons be aware of the various accessory EHL tendons and their potential use in problematic cases.

Examination of the accessory tendons of extensor hallucis longus muscle in fetuses

“…Denk et al (2002) found AT of EHL muscle in 70% of 47 amputated legs and eight cadavers. In the series of Denk et al (2002), EHL tendon was splitting into two as lateral and medial tendons at the level of the ankle (talocrural) joint, just beneath the inferior extensor retinaculum and attached to the same site (to the middle of the dorsal aspect of the base of the distal phalanx of the hallux). It was also given that the lateral tendons were thicker than the medial ones in only 15 out of 44 legs.…”

“…Some textbooks (Romanes, 1981) claim that it can be ''occasionally'' found while some others assert that EHL muscle ''usually'' gives AT (Standring et al, 2005). Also, studies on cadavers (Denk et al, 2002;Al-saggaf, 2003;Bibbo et al, 2004;Boyd et al, 2006) have reported several frequencies for these AT, varying between 35 and 81%. Thus, the first aim of this study is to determine the AT frequency of EHL muscle in fetuses.…”

Bilateral Tendon Variation of Extensor Hallucis Longus Muscle: Case Report

“…Bu çalışmalarda, MEHL tendonlarının, hem bazı ayak başparmağı deformitelerinde hem de rekonstrüktif cerrahide greft olarak kullanılabilme potansiyeline vurgu yapılmıştır. [4][5][6][7][8][9][10][11][12][13][14][15] M. extensor hallucis longus tendonunun varyasyonlarının sık görüldüğünü vurgulayan Uzel ve ark., ortopedi polikliniğine başvurmuş 35 yaşındaki bir kadın olguda, bilateral olarak m. tibialis anterior ve sol MEHL tendonunun bulunmadığını bildirmiştir. 3 Kaneff ve ark., MEHL'in erkeklerdeki varyasyonunu gelişimsel miyoloji açısından analiz ettikleri çalışmalarında, MEHL'in iki ayrı kas kitlesinden oluştuğunu ve gelişim süreci içinde bu iki kas kitlesinden birinin lateral tarafa diğerinin medial tarafa yöneldiğini belirtmektedirler.…”

“…Bunlara ek olarak çalışmada, bir kadavranın sağ MEHL lateral tendonu ile MEHB'nin tendonunun birleştiği de bildirilmektedir. 6,10 M. extensor hallucis longus'un varyasyonu ile ilgili en kapsamlı çalışmalardan birini yapan Alsaggaf, üç farklı tipte MEHL varyasyonunun bulunduğunu, 60 alt ekstremitenin 39 (%65)'unda MEHL'in tek tendonlu, 16 (%26,67)'sında iki tendonlu ve 5 (%8,33)'inde de üç tendonlu olduğunu bildirmektedir.…”

Unusual accessory tendon connecting the hallucal extensors

“…Specifically, supernumerary tendinous slips inserting onto the hallucal proximal phalanx or metatarsophalangeal (MP) joint capsule have been demonstrated to occur in the majority (approx. 72–87%) of lower limbs (Tate & Pachnik, 1976; Denk et al ., 2002; Bibbo et al ., 2004). Such accessory tendons may arise from the extensor hallucis longus muscle (EHL) or, less commonly, from the tibialis anterior (TA) or a separate muscle belly (Bibbo et al ., 2004).…”