Gantzer muscle. An anatomical study

Abstract

OBJECTIVE: The relationship of Gantzer muscle to the median and anterior interosseous nerve is debated. METHODS: Ìn an anatomical study with 80 limbs from 40 cadavers the incidence, origin, insertion, nerve supply and relations of Gantzer muscle have been documented. RESULTS: The muscle was found in 54 forearms (68% of limbs) and was supplied by the anterior interosseous nerve. It arose from the deep surface of the flexor digitorum superficialis muscle, (42 limbs), coronoid process (eight limbs) and medial epicondyle (seven limbs). Its insertion was to the ulnar part of flexor pollicis longus muscle. The Gantzer muscle always lay posterior to both the median and anterior interosseous nerve. CONCLUSION: The Gantzer muscle may contribute to the median nerve and anterior interosseous nerve compression. The muscle was found in 68% of limbs and should be considered a normal anatomical pattern rather than an anatomical variation. Level of Evidence IV, Case Series.

Accessory head of the flexor pollicis longus muscle: anatomical study and clinical significance

“…Afterwards Pai et al [17] classified the morphology in three groups: straplike (slender), fusiform and voluminous. In our series, the most frequent type was fusiform, consistent to the reported by Kara et al [12], Pai et al [17], El Domiaty et al [7], Caetano et al [3], Gunnal et al [9]. Regarding the morphometric data, the length of the muscle belly and the tendon have been reported to range between 60 and 80.4 mm and between 8 and 20.7 mm.…”

“…Regarding the origin of the AHFPL muscle, some authors have reported the medial epicondyle of the humerus as the most frequent site [1,6,10,13,14,22], others have reported that is the coronoid process [9,16,27]. In our series, the most frequent origin was the flexor digitorum superficialis muscle, similarly reported by Jones et al [11], El Domiaty et al [7], Kara et al [12] and Caetano et al [3]. However, a recent meta-analysis of 24 cadaveric studies found that the most common origin of the AHFPL was the medial epicondyle of the humerus [19].…”

“…In South American population, earlier reports are contradictory. Studies by Caetano et al [3] reveal a frequency of 67.5% and studies by Riveros et al [20] reveal a frequency of 10%. Including the present study, the consolidated prevalence of this group is 42.1%.…”

“…This discrepancy can be explained by the fact that in its origin the AHFPL is intimately related with other structures of the flexor mass, leading to a possible misidentification by authors [3,10,16,19]. It is necessary to do a meticulous dissection to determine the origin appropriately, because the FDS has fascicles originated in the coronoid process and medial epicondyle of the humerus.…”

“…The AHFPL has an oblique trajectory from medial to lateral aspect of the forearm below the FDS and then joins the flexor pollicis longus muscle (FPL) [10,21,27]. Moreover, the AHFPL may also give rise to a second tendinous contribution to the flexor digitorum profundus muscle (FDP) [3,11,16,22].…”