The m. omotransversarius belongs to extrinsic muscles of the thoracic limb. In dogs it is narrow and flat, laying laterally on the neck. M. omotransversarius originates from ala atlantis and terminates on spina scapulae distal third, acromion and fascia brachialis. The aim of the study was to showing difference in the origin of that muscle in dogs. The study was carried out on a crossbreed dog during the gross anatomy course at the Department of Anatomy, Histology and Embryology, Faculty of Veterinary Medicine, University of Zagreb. Left side: small tendon of m. omotransversarius unites with m. rhomboideus capitis and both originated at crista nuchae on occipital bone. A thin and narrow band of m. omotransversarius ran caudo-ventrally and join the rest of the muscle, which had origine on ala atlantis. Right side: M. omotransversarius was also split in two bands. Dorsal origin had two tendinous parts: the broader, caudodorsal tendon began from m. rhomboideus capitis, while the narrower ; cranioventral tendon began together with m. rhomboideus capitis at crista nuchae. Both parts united to a band, about three times stronger than that on the left side, and then join the rest of the muscle. On both sides m. omotransversarius terminated at the distal third of spina scapulae and acromion. Nomina Anatomica Veterinaria (2005) and veterinary anatomy literature describes only m. omotransversarius. Therefore, the presented anatomical finding is rather unusual for dogs. Generally, the two muscles, m. omotransversarius and m. omotransversarius dorsalis are present in Primates. Among carnivores, both are present in Mustelide and bears. In rabbits, one muscle splits into two units, which in our opinion was observed in presented case-study.

Veterinarska medicina

DOI: 10.1111/j.1439-0264.2010.01008_2.x