Английский язык для медиков: конспект лекций

Anterior triangle is bound by the sternocleidomastoid muse the mid-line of the neck, and the inferior border of the body of the mandible. Muscular triangle is bound by the sternocleidomastoid muscle, the superior belly of the omohyoid muscle, and the midline of the neck. Its contents include the infrahyoid (strap) muscles, which function to control movements the hyoid bone and larynx during speech and deglutition (swallowing). Carotid (vascular) triangle is bound by the ster-nocleidomastoid muscle, the superior belly of the omohyoid muscle and the posterior belly of the digastric muscle. The carotid triangle contains the following: Internal jugular vein; Common carotid artery, bifurcates at the upper border of the thyroid cartilage (i. e., vertebral level C3) to form the internal and external carotid arteries. The external carotid artery has six branches (i. e., the superior thyroid; the ascending pharyngeal, the lingual, the facial, the occipital, and the posterior auricular arteries). The supply structures of the neck and face; vagus nerve; hypoglossal nerve; internal and external laryngeal branches of the superior laryngeal branch of the vagus nerve. The internal laryge-al nerve conveys sensory information from the laryngeal mucosa above the level of the vocal folds, and the external laryngeal nerve supplies motor fibers to the cricothyroid, an intrinsic muscle of the larynx. Digastric (submandibular) triangle is bound by the anterior and posterior bellies of the digastric muscle and the inferi or border of the body of the mandible. The floor of this tri angle is formed by the hyoglos-sus and mylohyoid muscles. It contains the submandibular salivary gland. Submental triangle is bound by the anterior belly of the digastric muscle, the hyoid bone, and the midline of the neck. The floor of this triangle is formed by the mylohyoid muscle. It contains the submental lymph nodes. Root of neck: This area communicates with the superior medi astinum through the thoracic inlet. Structures of the region include the following: subclavian artery and vein. The subclavian artery passes poste rior to the scalenus anterior muscle, and the vein passes ante rior to it. Branches of the artery include: vertebral artery; thyrocervical trunk, which gives rise to the inferior thyroid, the transverse cervical, and the suprascapular arteries; Internal thoracic artery.

Phrenic nerve is a branch of the cervical plexus, which arises from C3, C4, and C5. It is the sole motor nerve to the diaphragm. It crosses the anterior scalene muscle from lateral to medial to enter the thoracic inlet.

Recurrent laryngeal nerve is a branch of the vagus nerve. This mixed nerve conveys sensory information from the laryngeal; mucosa below the level of the vocal folds and provides motor innervation to all the intrinsic muscles of the larynx except the cricothyroid muscle.

Thoracic duct terminates at the junction of the left subclavian and the left internal jugular veins. On the right side of the body, the right lymphatic duct terminates in a similar fashion.

Fascias of the neck: Superficial investing fascia encloses the platys-ma, a muscle of facial expression, which has migrated to the neck.

Deep investing fascia surrounds the trapezius and sternoclei – do-mastoid muscles.

Retropharyngeal (visceral) fascia surrounds the pharynx.

Prevertebral fascia invests the prevertebral muscles of the nee (i. e., longus colli, longus capitis). This layer gives rise to a derivative known as the alar fascia.

The major muscle groups and their innervations. A simple method of organizing the muscles of the neck is based on two basic principles: (1) The muscles may be arranged in group according to their functions; and (2) all muscles in a group share common innervation with one exception in each group.

Group 1: Muscles of the tongue. All intrinsic muscles plus all but one of the extrinsic muscles (i. e., those containing the suffix, glossus) of the tongue are supplied by CN XII. The one exception is palatoglos-sus, which is supplied by CN X.

Group 2: Muscles of the larynx. All but one of the intrinsic muscles of the larynx are supplied by the recurrent laryngeal branch of the vagus nerve. The sole exception is the cricothyroid muscle, which is supplied by the external laryngeal branch of the vagus.

Group 3: Muscles of the pharynx. All but one of the longitudinal and circular muscles of the pharynx are supplied by CNs X and XI (cranial portion). The sole exception is the stylopharyngeus muscle, which is supplied by CN IX.

Group 4: Muscles of the soft palate. All but one of the muscles of the palate are supplied by CNs X and XI (cranial portion). The sole exception is the tensor veli palatini, which is supplied CN V3.

Group 5: Infrahyoid muscles. All but one of the infrahyoid muscles are supplied by the ansa cervicalis of the cervical olexus (C1, C2, and C3). The exception is the thyrohyoid, which is supplied by a branch of C1. (This branch of C1 also supplies the geniohyoid muscle).