Is ultrasound effective in determining variation of the insertion of the extensor hallucis longus tendon?

Abstract

Background: The extensor hallucis longus (EHL) is located in the anterior compartment of the leg, between the tibialis anterior muscle and extensor digitorum longus. The EHL is characterized by a number of morphological variations, concerning mainly the accessory bands and their insertion. The aim of our research was to evaluate the effectiveness of ultrasound in determining the anatomical variations of the EHL. Methods: The morphology of the EHL was evaluated by ultrasound (high-frequency linear probe of Samsung RS80 apparatus) in 50 healthy volunteers. The types of EHL morphology were determined according to a threefold classification. Results: Only two types of the threefold anatomical classification were observed: Type I in 76 limbs (76%) and Type IIa in 24 limbs (24%). The accessory bands of the EHL were found in 24% of cases, all of which demonstrated a course that was located medially in relation to the main tendon. Conclusion: Ultrasound allows for visualization of the EHL; however, the potential recognition of morphological variance is limited.

Anatomical variations of the tibialis anterior tendon

“…It is quite common to find additional bands/tendons in the anterior compartment of the leg (Olewnik, Podgórski, Polguj, & Topol, 2019), being observed in between 20 and 100% of TAMs (Brenner, 2002; Musiał, 1963; Olewnik, Podgórski, Polguj, & Topol, 2019; Willegger, Seyidova, Schuh, Windhager, & Hirtler, 2017). In contrast, the prevalence of accessory bands of the EHL ranges from 24 to 42.5% (Al‐Saggaf, 2003; Olewnik, Podgórski, Polguj, Ruzik, & Grzelak, 2020; Olewnik, Podgórski, Polguj, Ruzik, et al, 2019) and is rare for the extensor digitorum longus (Tezer & Cicekcibasi, 2012). In contrast, about 55% of examined fibularis tertius samples demonstrate additional originating from the extensor digitorum longus, or independently (Olewnik, 2019a).…”

Case report of the double-headed extensor hallucis longus

“…However, severalstudieshave described variations of this insertion. [1,7,17,22,26,27] Al-Sagaff described three types of possible distal attachment. [1]Type I (most common) was characterized as a single tendinous insertion on the dorsal aspect of the base of the distal phalanx of the big toe.…”

“…[2,34] The role of the EHL is to extend the great toe. It is also responsible for dorsiflexion of the foot, adjunct foot eversion and inversion.There are EHL classifications for fetuses and adults, and more recently an exact classification was proposed by Zielinska et al [1,7,17,22,26,27,38], distinguishing three types of EHL with subtypes. Anatomical variations of the EHL can predispose to hallux valgus deformity, tendonitis and acute compartment syndrome.…”

Anatomical Variations of the Tibialis Anterior Tendon Insertion: An Updated and Comprehensive Review

“…[15], this type was described as a tendinous part divided into one wide insertion (located on the medial cuneiform) and some thin fibers attached to the base of the first metatarsal. ** this type was not included in the classification system by Olewnik et al [11].…”

“…Palpation may be insufficient in cases of parietal tears, bursitis or tendinopathy. In these cases, diagnostic imaging, such as ultrasound (USG) with colour Doppler, computed tomography (CT) or magnetic resonance imaging (MRI), should be initiated [11,12].…”