Regional anatomy of (1)

扬州大学医学院 解剖教研室 Parts and regions of the neck

Boundaries  Superior－inferior border of mandible, angle of mandible, tip of mastoid process, superior nuchal line, external occipital protuberance  Inferior－jugular notch, sternoclavicular joint, superior border of clavicle, acromion, spinous processes of C7

(Greater) supraclavicular fossa Lesser supraclavicular fossa Suprasternal fossa

表面标志 surface landmark 表面标志 Surface Landmark

 舌骨 Hyoid(H)

 甲状软骨 Thyroid cartilage(T)

 喉结节 Laryngeal prominence(P)

 环状软骨 Cricoid cartilage (C)

 第1气管环 The first tracheal ringe(1)

 甲状腺峡 Isthmus(S) Regions

 proper neck 固有颈部

 Anterior region of neck

 Lateral region of neck

 Sternocleidomastoid region  Nape 项部 Ⅰ.Anterior region of neck

Suprahyoid region 舌骨上区  Infrahyoid region 舌骨下区 Submental triangle  Carotid triangle (颏下三角) (颈动脉三角) Submandibular triangle  Muscular triangle (下颌下三角) (肌三角)

Ⅱ.Lateral region of neck  Occipital triangle 枕三角  supraclavicular triangle 锁骨上三角 or (great supraclavicular fossa) 锁骨上大窝 Ⅲ.Sternocleidomastoid region Ⅰ.the first layer ---Skin  The natural line of cleavage of the skin are constant and run almost horizontally around the neck

Ⅱ.Superficial  Consists of fat and connective tissue  Contents  Platysma  Superficial veins  Anterior jugular v.  External jugular v.  Cutaneous  Lesser occipital n.  Greet auricular n.  Transverse of neck  Supraclavicular n.  Cervical branch of facial n. Platysma  The main action of the platysma:①draws corners of mouth inferiorly and widens it as in expressions of sadness and fright; ②draws the skin of neck superiorly when teeth are “clenched”. Ⅲ.Cervical fascia 颈筋膜－three layers

Superficial layer (investing fascia 封套筋膜)

 Encloses trapezius, sternocleidomastoid, and parotid and submandibular glands  Attached to bony landmarks of upper and lower boundaries of neck

Pretracheal layer 气管前层  Encloses viscera of neck: pharynx, esophagus ,, ,, thyroid gland and parathyroid glands  Completely surrounds thyroid gland, forming a sheet for it, and bind the gland to larynx

Prevertebral layer 椎前层

 Lies anterior to bodies of cervical vertebrae and prevertebral muscles; extends from base of skull downward into the superior mediastinum, continuous with anterior longitudinal lig.

 Covers subclavian vessels and roots of brachial plexus  Extends into upper limb as axillary sheath 颈动脉鞘  Formed by components of all three layers of  Contains common and internal carotid arteries, internal jugular vein, and vagus nerve  Ansa cervicalis located on its anterior surface Suprasternal space 胸骨上间隙  Inferiorly the investing fascia splits into two layers, which are attached to the anterior and posterior margins of the upper border of the manubrium, between these two layers is a small space, called the suprasternal space  Contains connective tissue, and sometimes a lymph node Pretracheal space 气管前间隙  Lies between pretracheal layer and cervical part of trachea  Contains : inferior thyroid v., unpaired thyroid venous plexus, brachiocephalic trunk and left brachiocephalic v.

Retropharyngeal space 咽后间隙  Lies between prevertebral layer and 椎前间隙  Lies between prevertebral muscles, cervical part of vertebral column and prevertebral layer Suprahyoid region

Submental triangle 颏下三角  Lies below the chin and is bounded laterally by anterior bellies of digastric, and inferiorly by the body of hyoid bone  Covered by skin, superficial fascia and investing fascia  Floor－mylohyoid muscles  Contents－submental lymph nodes Submandibular triangle 下颌下三角  Bounded by anterior and posterior bellies of digastric and lower border of the body of the mandible  Covered by skin, superficial fascia, platysma and investing fascia  Floor: mylohyoid m., hyoglossus m. and middle constrictor of pharynx  Contents－submandibular gland, facial a., v., hypoglossal n. lingual n., submandibular ganglion and submandibular lymph nodes

Infrahyoid region Carotid triangle 颈动脉三角  Bounded by anterior border of sternocleidomastoid, superior belly of omohyoid m. and posterior belly of digastric muscles  Covered by skin, superficial fascia, platysma and investing fascia  Floor－prevertebral fascia and lateral wall of pharynx  Contents－common carotid a. and its branches, internal jugular v. and its tributaries, hypoglossal n. with its descending branches, the accessory and vagus nerves, and part of the chain of deep cervical lymph nodes

Sternocleidomastoid region 胸锁乳突肌区

 Covered by sternocleidomastoid

 Contents

 Carotid sheath

 Cervical plexus

 Cervical part of sympathetic trunk

 Ansa cervicalis (ⅰ) 3 vessels Common carotid artery 颈总动脉  Origin (arises from)

 Brachiocephalic trunk on the right

 Aortic arch on the left  Ascends in neck to upper border of thyroid cartilage; bifurcates into internal and external carotid arteries  Carotid sinus 颈动脉窦 (baroreceptor), located at a local dilation of terminal part of common carotid artery and beginning of internal carotid artery, sensitive to blood pressure changes  Carotid glomus 颈动脉小球 (chemoreceptor), lies posterior to the point of bifurcation of common carotid artery, senses changes in blood carbon dioxide (oxygen) levels

Branches of external carotid a.  Superior thyroid a. 甲状腺上动脉－descends to supply upper pole of thyroid gland and larynx

 Lingual a. 舌动脉

 Facial a. 面动脉

 Maxillary a. 上颌动脉

 Superficial temporal a. 颞浅动脉 Veins draining the neck Internal jugular vein 颈内静脉  Begin at jugular foramen, descending to join the subclavian vein to form brachiocephalic vein  Lies lateral first to internal and then to common carotid a. within carotid sheath  Chief extracranial tributaries  Common facial vein 面总静脉  Lingual v. 舌静脉  Pharyngeal v. 咽静脉  Superior thyroid v.甲状腺上静脉  Middle thyroid v. 甲状腺中静脉

(ⅱ) 3 nerves Vagus nerve (Ⅹ)  Leaves skull via jugular foramen

 Descends in the neck in carotid sheath between internal (or common) carotid artery and internal jugular vein  Branches  Superior laryngeal nerve 喉上神经 passes down side of pharynx and given rise to  Internal branch 内支 which pierces thyrohyoid membrane to innervates mucous membrane of larynx above fissure of glottis  External branch 外支 which innervates cricothyroid  Cervical cardiac branches 颈心支 : descending to terminate in cardiac plexus  Recurrent laryngeal nerves 喉返神经  Ascend in tracheo-esophageal groove  Enter larynx posterior to cricothyroid joint, the nerve is now called inferior laryngeal nerve  Innervations: laryngeal mucosa below fissure of glottis and all laryngeal muscles except cricothyroid m. Accessory n. (Ⅺ ) 副神经  Deep to posterior belly of digastric  Supplies sternoclidomastoid and trapezius muscle

Hypoglossal n.(Ⅻ) 舌下神经  Descends between internal carotid a. and internal jugular v., hooks around external carotid a., to lie on the hyoglossus m. before entering tongue  Supplies muscles of tongue

Cervical part of sympathetic trunk 颈交感干  Formed by superior , middle and inferior cervical ganglia and interganglionic branches  Superior cervical ganglion: largest, situated in front of transverse processes of C1~C3 vertebra  Middle cervical ganglion: smallest, is at level of transverse processes of C6 vertebra  Inferior cervical ganglion: situated at level of C7 vertebra, and may be fused with first thoracic ganglion to form cervicothoracic ganglion 颈胸神经节 Cervical plexus Formation : formed by anterior rami of C1-C4 spinal nerves Position: lies in front of the origin of levator scapulae and scalenus medius and deep to the superior part of the sternocleidomastoid Branches

 Cutaneous branches: emerge around middle of posterior border of sternocleidomastoid, to supply skin of neck and scalp between auricle and external occipital protuberance

 Lesser occipital n. 枕小神经

 Greet auricular n. 耳大神经

 Transverse nerve of neck 颈横 神经

 Supraclavicular n. 锁骨上神经

 Muscular branches: supply the deep muscles of neck  Phrenic nerve 膈神经(anterior rami of C3-C5)  Lies on anterior scalene, deep to fascia  To diaphragm (motor and sensory)  Ansa cervicalis 颈袢:  Hypoglossal nerve gives off superior root of ansa , (composed of fibers picked up from nerve C1)  Joins inferior root of ansa (composed of fibers picked up from anterior rami of C2- C3) to form a loop, the ansa cervicalis, which supplies

Posterior belly of digastic muscle  Superficial－great auricular n., retromandibular v., cervical branch of facial n.  Deep－internal and external carotid a., internal jugular v., Ⅹ～Ⅻ cranial n. and cervical part of sympathetic trunk

Infrahyoid region

Muscular triangle 肌三角  Bounded by midline of the neck, superior belly of the omohyoid and anterior border of the sternocleidomastoid.  Covered by skin, superficial fascia, platysma, anterior jugular v., cutaneous n. and investing fascia  Floor－prevertebral fascia  Contents－ thyroid gland, parathyroid gland, cervical part of trachea and esophagus and relating vessles,nerves,lymph. Thyroid gland 甲状腺

Shape and position  H-shape  Left and right lobes: lie on either side of inferior part of larynx and superior part of trachea, extend from middle of thyroid cartilage to level of sixth trachea cartilage  Isthmus: overlies 2nd to 4th tracheal cartilage  Pyramidal lobe: some times arises from isthmus covering of thyroid 1) Fibrous capsule:(false capsule) A sheath of pretracheal fascia which is attached to arch of cricoid and thyroid cartilages, hence, the thyroid gland moves with larynx during swallowing and oscillates during speaking. 甲状腺假被膜

甲状腺真被膜 囊鞘间隙

甲状腺悬韧带 covering：甲状腺被膜covering of thyroid ：分为甲状腺假被膜 false capsule （即甲状腺鞘，由气管前筋膜包裹甲状腺而成）和甲状腺真被膜 true capsule （即甲状腺纤维囊），两者之间的间隙为囊鞘间隙（内有疏 松结缔组织、血管、神经和甲状旁腺等）。甲状腺悬韧带suspensory ligament of thyroid Arteries of thyroid gland and nerves of larynx

Superior thyroid a.  Branch of external carotid a.  Runs superficial and parallel to the external branch of superior laryngeal n. to reach the upper pole of thyroid gland  Gives off superior laryngeal a. in company with internal branch of superior laryngeal n.

Superior laryngeal nerve  Internal branch which pierces thyrohyoid membrane to innervates mucous membrane of larynx above fissure of glottis  External branch is fine n., which descends in company with the superior thyroid a. and supplies cricothyroid

Inferior thyroid artery 甲状腺下动脉  Branch of thyrocervical trunk off subclavian a.  Turns medially and downward, reaches the posterior border of the thyroid gland and is closely related to the recurrent laryngeal n.  Supplies inferior pole of thyroid gland Recurrent laryngeal nerves 喉返神经  Ascend in tracheo-esophageal groove  Pass deep to the lobe of the thyroid gland and come into close relationship with the inferior thyroid a.  Cross either in front of or behind the artery of may pass between its branches  Nerves enter larynx posterior to cricothyroid joint, the nerve is now called inferior laryngeal nerve  Innervations: laryngeal mucosa below fissure of glottis , all laryngeal laryngeal muscles except cricothyroid

Arteria thyroid ima 甲状腺最下动脉  May arise (4%) from the brachiocephalic a. or aortic arch Venous drainage  Superior and middle thyroid veins into internal jugular vein  Inferior thyroid veins to left brachiocephalic vein

Parathyroid gland 甲状旁腺

 Yellowish-brown, ovoid bodies  Position

 Two superior parathyroid glands: lie at junction of superior and middle third of posterior border of thyroid gland

 Two inferior parathyroid glands: lie near the inferior thyroid artery, close to the inferior poles of thyroid gland  Function: regulate calcium and phosphate balance and is therefore essential for life Cervical part of trachea 气管颈部

 Begins at lower end of larynx－level of C6 vertebra  Consists of a series of incomplete cartilage rings  Extends into thorax  Relations in the neck  Anteriorly The skin , superficial fascia, investing fascia, suprasternal space and jugular arch, infrahyoid muscles and pretracheal fascia, isthmus of thyroid gland ( in front of the 2nd to 4th tracheal cartilage), inferior thyroid v. and unpaired thyroid venous plexus, arteria thyroid ima ( if present), and left brachiocephalic v. in child

 Laterally The lobes of the thyroid gland ( down as far as the sixth ring) and the carotid sheath

 Posteriorly The right and left recurrent laryngeal nerves, the esophagus Cervical part of esophagus 食管颈部

 Connecting the pharynx at level of C6 vertebra  Consists of smooth muscle tube  Relations of the neck  Anteriorly Trachea , recurrent laryngeal nerves ascend, one on each side, in the groove between the trachea and esophagus  Posteriorly Prevertebral layer of cervicl fascia, longus colli, and vertebral column  Laterally Lobe of the thyroid gland and carotid sheath Lateral region of neck 颈外侧区

 Bounded by posterior border of sternocleidomastoid, anterior border of trapezius and middle third of clavicle  Divided by inferior belly of omohyoid into occipital and supraclavicular triangles Triangle of the vertebral a. 椎动脉三角  Boundaries  Medially－longus colli  Laterally－scalenus anterior  Inferiorly－first part of subclavian a.  Apex－transvese procss of C6  Posteriorly－cupula of pleura, transvese procss of C7, anterior rami of C8 spinal nerves, costal neck of 1st rib  Anteriorly－carotid sheath, phrenic n. and arch of thoracic duct (left)  Contents  Vertebral a.  Inferior thyroid a.  Cervical part of sympathetic trunk  Cevicothoracic ganglion Occipital triangle 枕三角  Bounded by posterior border of sternocleidomastoid, anterior border of trapezius and superior border of inferior belly of omohyoid  Covered by skin, superficial fascia, and investing fascia  Floor－prevertebral fascia and scalenus anterior, scalenus medius, scalenus posterior, splenius capitis and levator scapulae  Conents  Accessory n.－emerges above the middle of the posterior border of sternocleidomastoid and crosses the occipital triangle to trapezius  Cervical and brachial plexuses

Supraclavicular triangle 锁骨 上三角  Bounded by posterior border of sternocleidomastoid, inferior belly of omohyoid and middle third of clavicle  Covered by skin, superficial fascia, and investing fascia  Floor－prevertebral fascia and inferior parts of scalenus  Conents  Subclavian v. and venous angle  Subclavian a.  Brachial plexus

Cutaneous nerves and superficial veins

Lesser occipital n.

External jugular vein

Greet auricular n. Transverse nerve of neck Supraclavicular n. Anterior jugular vein Submendibular gland

Digastric Accessory n.

Hypoglossal n.

Superior thyroid a. Ansa cervicalis Cervical plexus

Sternothyroid Phrenic n. Sternohyoid Omohyoid Vagus n. Hypoglossal n.

Vagus n. Internal branch

Superior thyroid a. External branch Vertebral a.

Inferior thyroid a. Root of neck 颈根部

 Formed at thoracic inlet by

 Anteriorly－manubrium sterni

 Posteriorly－body of first thoracic vertebra

 Laterally－first rib and costal cartilage 

 Digastric 二腹肌

 Stylohyoid 茎突舌骨肌

 Mylohyoid 下颌舌骨肌

 Geniohyoid 颏舌骨肌 Elevate (raise) hyoid bone and depress mandible.

 Infrahyoid muscle

 Sternohyoid 胸骨舌骨肌

 Sternothyroid 胸骨甲状肌

 Thyrohyoid 甲状舌骨肌

 Omohyoid 肩胛舌骨肌 Depress hyoid or larynx after elevation  Deep group

 Lateral

 Scalenus anterior 前斜角肌  Scalenus medius 中斜角肌  Scalenus posterior 后斜角肌

 Medial

 longus capitis 头长肌  longus colli 颈长肌 Flex the head, bends the neck forward Scalenus anterior  Origin: transverse processes of C3-C6.  Insertion: tubercle for scalenus anterior  Action: unilateral, bends neck laterally; bilateral, elevate first rib, an accessory muscle of inspiration; if rib is fixed, flex neck anteriorly Scalene fissure 斜角肌间隙 Above the first rib, there is a triangular space between scalenus anterior and midius. The brachial plexus and the subclavine a. emerge from this space. 六、解剖与观察 Dissection and Observation 1.Make a median skin incision 2.Reflect the skin flaps 3.Reflect the platysma 4.Dissect the superficial structures 5.Dissect the submental triangle 6.Dissect the submandibular triangle 1.Make a median skin incision from the mental symphysis to the suprasternal notch. 2.Reflect the skin flaps laterally to the anterior border of the trapezius to expose the platysma directly. 3.Divide the platysma along the upper border of the clavicle and reflect it upwards to the mandible. Do not damage the underlying structures. 4.Look for and expose the superficial structures of the neck.

5.Clean boundaris of the submental triangle 6. Cut through the investing fascia to exopse the submandibular gland, the facial vein, the cervical branches of the facial nerve and submandibular lymph nodes. • Divide Clean the mylohyoidorigin of the and anterior cut it alongbelly of the the median digastric line and and reflectimmediately it downwards. above the Look hyoid.Reflect for the submental the mylohyoid vessels muscle and the mylohyoidupwards• Identify to nerve theexpose facial on the the arteryhypoglossal mylohyoid. and nerve follow on it the to hyoglossus.its origin.  Look for the lingual artery and vein between the hypoglossus nerve and the greater horn of the hyoid, trace it to the submandibular triangle.

• Look for the duct of submandibular gland , the submandibular ganglion, and lingual nerve.  Homework 1.Describe the position of the facial dangerous triangle and its clinical significance . 2.What is the pterion point. 3.What is the carotid sheath． 4. What are the structures which lie deep to the posterior belly of digastric arranged?