A study of anatomical variability of the omohyoid muscle and its clinical relevance

OBJECTIVE: The omohyoid muscle is a long, thin muscle consisting of superior and inferior bellies and an intermediate tendon, which runs obliquely in the lateral cervical region. The omohyoid is important in neck dissections because it is the surgical landmark for level III and IV lymph node metastases. METHODS: In the present study, the anterior and posterior triangle of the neck was dissected in 35 male cadavers and observed for variations in the omohyoid bilaterally. Observations were focused on variations in number, attachments, and position of omohyoid. RESULTS: Among the 35 cadavers studied, double omohyoid was present in one cadaver, inferior belly originated from the clavicle in three cadavers, superior belly merged with the sternohyoid in two cadavers, and the omohyoid received additional slips from the sternum in one cadaver. Standard attachment and position of the omohyoid was observed in the remaining cadavers. CONCLUSION: Variations of this muscle are important because of its close relation to the large vessels and brachial plexus. Because of the direct adhesion of the intermediate tendon to the anterior wall of the internal jugular vein and its connection with it through a thin lamina of the pretracheal layer of the cervical fascia, the contraction of the omohyoid muscle has a direct effect on the lumen of this vessel

A study of anatomical variability of the omohyoid muscle and its clinical relevance

OBJECTIVE: The omohyoid muscle is a long, thin muscle consisting of superior and inferior bellies and an intermediate tendon, which runs obliquely in the lateral cervical region. The omohyoid is important in neck dissections because it is the surgical landmark for level III and IV lymph node metastases. METHODS: In the present study, the anterior and posterior triangle of the neck was dissected in 35 male cadavers and observed for variations in the omohyoid bilaterally. Observations were focused on variations in number, attachments, and position of omohyoid. RESULTS: Among the 35 cadavers studied, double omohyoid was present in one cadaver, inferior belly originated from the clavicle in three cadavers, superior belly merged with the sternohyoid in two cadavers, and the omohyoid received additional slips from the sternum in one cadaver. Standard attachment and position of the omohyoid was observed in the remaining cadavers. CONCLUSION: Variations of this muscle are important because of its close relation to the large vessels and brachial plexus. Because of the direct adhesion of the intermediate tendon to the anterior wall of the internal jugular vein and its connection with it through a thin lamina of the pretracheal layer of the cervical fascia, the contraction of the omohyoid muscle has a direct effect on the lumen of this vessel

Hypoplastic posterior tibial artery and the enlarged peroneal artery supplying the posterior crural region: a rare variation Artéria tibial posterior hipoplásica e a artéria peroneal aumentada suprindo a região crural posterior: uma variação rara

Arterial variations of distal parts of lower extremities are well-documented and can be demonstrated with the help of Doppler ultrasound or by arteriography. However, absence or variation of posterior tibial artery is considered a rare finding. We present a case of hypoplastic posterior tibial artery that terminated by supplying soleus muscle. The variant arterial supply to the sole was provided by the enlarged peroneal artery that continued as the lateral plantar artery. The awareness of these variations is important to vascular surgeons while performing arterial reconstructions in femorodistal bypass graft procedures, and also to orthopedists during surgical clubfoot release.<br>Variações arteriais de partes distais dos membros inferiores estão bem documentadas e podem ser demonstradas com o auxílio de ultra-sonografia Doppler ou por arteriografia. Entretanto, a ausência ou variação da artéria tibial posterior é um raro achado. Apresentamos um caso de artéria tibial posterior hipoplásica que terminava suprindo o músculo solear. Esse suprimento arterial variante foi fornecido pela artéria peroneal aumentada que continuava como artéria plantar lateral. Estar consciente dessas variações é importante para cirurgiões vasculares ao realizarem reconstruções arteriais em procedimentos de derivação femorodistal, bem como para ortopedistas durante correção cirúrgica do pé torto

Anatomy of the Hamstrings

This chapter will provide the anatomical foundation for the content to come in later portions of this book. It will begin with an overview of the proximal insertion sites of the muscles that comprise the hamstring group. The proximal tendons and musculotendinous junctions (MTJs) of semimembranosus, semitendinosus and the long and short heads of biceps femoris long head will then be described, highlighting the differences in structure between each of the muscles. The distinct architectural characteristics of each muscle belly (e.g. size, fascicle orientation within and between muscles) will be outlined, followed by the structure of the distal tendons and MTJs. Finally, a summary is provided of the neurovascular supply of the hamstrings