Dissection of the neck
This presentation is the property of its rightful owner.
Sponsored Links
1 / 95

Dissection of the Neck PowerPoint PPT Presentation


  • 151 Views
  • Uploaded on
  • Presentation posted in: General

Dissection of the Neck. Surface Anatomy Surface landmarks : 1 suprasternal (jugular) notch(fossa), 2 hyoid bone, 3 cricoid cartilage, 4 thyroid cartilage, 5 sternocleidomastoid , 6 great supraclavicular fossa. Dissection of the Posterior Triangle of the Neck.

Download Presentation

Dissection of the Neck

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript


Dissection of the neck

Dissection of the Neck


Dissection of the neck

Surface Anatomy

Surface landmarks :1suprasternal (jugular) notch(fossa),

2 hyoid bone, 3 cricoid cartilage, 4 thyroid cartilage,

5 sternocleidomastoid, 6 great supraclavicular fossa


Dissection of the posterior triangle of the neck

Dissection of the Posterior Triangle of the Neck

Boundaries and Contents of the Posterior Triangle.

The boundaries of the posterior triangle are the sternocleidomastoid, the trapezius, and the clavicle. The triangle is roofed over by the investing layer of deep cervical fascia.


Dissection of the neck

Make a midline skin incision from the point of the chin (symphysismenti) to the suprasternal notch. Continue the upper end of the incision backward and laterally along the lower border of the body of the mandible.


Dissection of the neck

At the angle of the mandible, extend the incision backward, below the ear to the mastoid process and then along the superior nuchal line. From the lower end of the midline incision at the suprasternal notch, make an incision along the upper border of the clavicle to the acromion process.


Dissection of the neck

Now carefully reflect the skin flaps laterally to expose the anterior and posterior triangles and the sternocleidomastoid muscle. Avoid damaging the underlying platysma muscle or the supraclavicular and accessory nerves.


Dissection of the neck

If the arm has already been dissected, the skin will have been reflected from the back of the neck; the trapezius muscle will also been reflected laterally.


Superficial fascia platysma cutaneous nerves and vessels

Superficial Fascia, Platysma, Cutaneous Nerves and Vessels.


Dissection of the neck

The superficial fascia is relatively thin and contains little fat; however, it possesses the platysma muscle. Carefully expose the paltysma muscle and note that its fibers arise from the superficial fascia covering the upper part of the pectoralis major muscle.


Dissection of the neck

The fibers form a thin, broad sheet that passes upward and medially across the clavicle, covering the lower anterior part of the posterior triangle and the greater part of the anterior triangle. The muscle is inserted into the lower border of the body of the mandible and the angle of the mouth.


Dissection of the neck

Divide the platysma along the upper border of the clavicle and reflect it upward and forward. Do not damage the underlying supraclavicular nerves and the external jugular vein that lie deep to it.


Dissection of the neck

Locate the three supraclavicular nerves and note that they descend over the clavicle to supply the skin over the thoracic wall down as far as the sternal angle.


Dissection of the neck

The lesser occipital nerve runs upward along the posterior border of the sternocleidomastoid muscle to be distributed to the skin over the auricle and mastoid process.


Dissection of the neck

The great auricular nerve runs upward and forward to supply the skin over the angle of the mandible and the auricle.


Dissection of the neck

Identify the external jugular vein and follow it superiorly to behind the angle of the mandible, where the external jugular is formed by the union of the posterior branch of the retromandibular vein and the posterior auricular vein. Trace the external jugular vein downward until it pierces the deep fascia. This vein varies considerably in size.


Dissection of the neck

Now clean the sternocleidomastoid muscle and secure the cutaneous branches of the cervical plexus as they pierce the deep fascia at the posterior border of the sternocleidomastoid muscle.


Dissection of the neck

The transverse cutaneous nerve crosses the sternocleidomastoid horizontally to supply the skin over the anterior triangle. The supraclavicular nerves, medial, intermediate, and lateral, descend over the clavicle, where they have already been secured.


Dissection of the neck

Now continue to reflect the platysma as far as the mandible. At the angle of the mandible, examine the deep surface of the platysma and attempt to identify the cervical branch of the facial nerve, which emerges from the lower end of the parotid gland to supply the platysma muscle.


Boundaries and contents of the posterior triangle

Boundaries and Contents of the Posterior Triangle.


Dissection of the neck

The boundaries of the posterior triangle are the sternocleidomastoid, the trapezius, and the clavicle. The triangle is roofed over by the investing layer of deep cervical fascia.


Dissection of the neck

Examine the sternocleidomastoid and the trapezius muscles again. Identify and clean the inferior belly of the omohyoid muscle and note that this muscle subdivides the posterior triangle into an upper large occipital triangle and a lower smaller subclavian triangle (supraclavicular triangle).


Dissection of the neck

Carefully clean the contents of the posterior triangle from the apex to the base. Secure the occipital artery as it crosses the apex. Identify the spinal part of the accessory nerve as it emerges from the posterior border of the sternocleidomastoid and follow it across the triangle on the levator scapulae until it disappears under the anterior border of the trapezius muscle.


Dissection of the neck

Identify also the third and fourth cervical nerves, which run to the trapezius with the accessory nerve. Identify and clean the roots and trunks of the brachial plexus, which lie deeply in the lower anterior part of the posterior triangle.


Dissection of the neck

The roots pass downward and laterally, entering the triangle between the scalenus anterior and medius muscles. The roots join one another to form the upper, middle, and lower trunks of the plexus, which continue laterally in front of the scalenus medius to enter the axilla in the interval between the clavicle and the first rib.


Dissection of the anterior triangle of the neck

Dissection of the Anterior Triangle of the Neck


Dissection of the neck

The anterior triangle is bounded by the lower margin of the mandible above, the sternocleidomastoid posterior, and the midline of the neck anteriorly.


Superficial fascia platysma cutaneous nerves and vessels1

Superficial Fascia, Platysma, Cutaneous Nerves and Vessels


Dissection of the neck

The superficial fascia contains a variable amount of fat and the platysma. The platysma muscle should have been completely reflected upward to the lower margin of the mandible.


Dissection of the neck

Identify again the cervical branch of the facial nerve as it leaves the parotid gland and runs forward, deep to the platysma, to supply it. Trace the transverse cutaneous nerve as it passes forward, across the sternocleidomastoidmuscle, to its distribution.


Dissection of the neck

Identify and clean the anterior jugular vein as it lies in the superficial fascia near the midline and follow it inferiorly until it pierces the investing layer of deep cervical fascia. The anterior jugular vein is very variable in size.


Dissection of the neck

Investing Layer of deep Cervical Fascia.Carefully remove the investing layer of the deep cervical fascia from the body of the hyoid bone above to the suprasternal notch below. Note that the fascia splits inferiorly into anterior and posterior layers, which are attached to the anterior and posterior border of the suprasternal notch.


Dissection of the neck

Identify the suprasternal space that lies between the anterior and posterior layers of fascia and secure the jugular arch within the space that connects the anterior jugular veins to one another.


Dissection of the neck

Now trace the anterior jugular vein laterally, deep to the sternocleidomastoid muscle, to where it joins the external jugular vein.


Dissection of the neck

Subdivisions of the Anterior Triangle.The anterior and posterior bellies of the digastric muscle and the superior belly of the omohyoid muscle subdivide the anterior triangle into four subsidiary triangles, namely, the submental triangle, the digastric triangle, the carotid triangle, and the muscular triangle.


Dissection of the neck

Carefully remove the remaining pierces of the investing layer of the deep cervical fascia that roofs over the anterior triangle of the neck.


Dissection of the neck

Submental triangle. Identify the boundaries of this triangle. Note that it is bounded anteriorly by the midline of the neck, laterally by the anterior belly of the digastric muscle, and inferiorly by the body of the hyoid bone.


Dissection of the neck

Clean the anterior belly of the digastric muscle and note that it arises from the body of the mandible. Note that the mylohyoid muscle forms the floor of the triangle. Identify within the triangle, if possible, the submental lymph nodes.


Dissection of the neck

Digastric triangle.Confirm that the boundaries of the triangle are as follows: anteriorly, the anterior belly of the digastric muscle; posteriorly, the posterior belly of the digastric and the stylohyoid muscles; superiorly, the lower border of the body of the mandible.


Dissection of the neck

Note that the two bellies of the digastric muscle are united by an intermediate tendon, which lies just above the body of the hyoid bone. Note also that the tendon is bound down to the hyoid bone by a loop of deep fascia.


Dissection of the neck

Study the stylohyoid muscle. Follow it downward and forward along the upper border of the posterior belly of the digastric muscle. Note that its tendon of insertion, which is attached to the junction of the body with the greater cornu of the hyoid bone, is pierced by the intermediate tendon of the digastric muscle.


Dissection of the neck

Now expose the submandibular lymph nodes, the facial vein, and the superficial part of the submandibular salivary gland. Identify and clean the posterior border of the mylohyoid muscle and observe that this muscle together with the hyoglossus muscle forms the floor of the digastric triangle.


Dissection of the neck

Secure the facial artery as it curves round the lower border of the body of the mandible. Identify the mylohyoid nerve as it lies on the mylohyoid muscle deep to the body of the mandible. The mylohyoid nerve supplies the mylohyoid muscle and the anterior belly of the digastric muscle.


Dissection of the neck

Identify the hypoglossal nerve as it crosses the lingual artery and passes forward on the hyoglossus muscle deep to the posterior border of the mylohyoid muscle.


Dissection of the neck

Carotid triangle. Note that the carotid triangle lies behind the hyoid bone and is bounded superiorly by the posterior belly of the digastric, inferiorly by the superior belly of the omohyoid, and posteriorly by the anterior border of the sternocleidomastoid muscle.


Dissection of the neck

Carefully remove the fascia within the triangle and identify the internal jugular vein laterally protruding from beneath the anterior border of the sternocleidomastoid muscle. Next identify the common and internal carotid arteries medial to the internal jugular vein.


Dissection of the neck

Then secure the external carotid artery that lies anteromdial to the internal carotid artery. Note the presence of the deep cervical lymph nodes in close relationship with the internal jugular vein.


Dissection of the neck

Identify and clean the lingual, facial, and superior thyroid veins and note that they drain into the internal jugular vein. Identify the tip of the greater cornu of the hyoid bone. This, together with the posterior belly of the digastric muscle, are important landmarks in the neck for reference purposes.


Dissection of the neck

Identify the hypoglossal nerve as it curves forward from beneath the occipital artery. Note that the hypoglossal nerve lies at first between the internal jugular vein and the internal carotid artery. Expose the descending branch and the nerve to the thyrohyoid muscle. Identify the descending cervical nerve.


Dissection of the neck

Carefully remove the anterior part of the carotid sheath, leaving the descending branch of the hypoglossal nerve and the descending cervical nerve intact. Clean the internal jugular vein and the carotid arteries. Identify the vagus nerve. Identify and clean the superior thyroid, facial, lingual, and occipital branches of the external carotid arteries.


Dissection of the neck

Expose the internal laryngeal nerve and its accompanying artery just before they pierce the thyrohyoid membrane. Trace the nerve superiorly to the superior laryngeal branch of the vagus. Dissect out the slender external laryngeal nerve and follow it downward to the cricothyroid muscle.


Dissection of the neck

2.


Dissection of the neck

Identify, but do not disturb, the hyoglossus muscle, the thyrohyoid muscle, and the superior, middle, and inferior constrictor muscles of the pharynx. Understand that these muscles form the medial part of the floor of the carotid triangle. Deflect the carotid arteries medially and identify the sympathetic trunk, which lies posterior to the carotid sheath.


Dissection of the neck

Muscular triangle. Expose the boundaries of the triangle. It is bounded by the midline of the neck anterior, superiorly by the superior belly of the omohyoid, and inferiorly by the anterior border of the sternocleidomastoid muscle. Note that the triangle contains the infrahyoid muscles, which lie on each side of the midline between the hyoid bone and the sternum.


Dissection of the neck

Clean the sternohyoid and superior belly of the omohyoid and identify the pretracheal fascia. Separate the sternohyoid muscles on the two sides and identify the following structures in or near the midline below the hyoid bone:


Dissection of the neck

(1)the thyrohyoid membrane, which fills in the interval between the hyoid bone and the thyroid cartilage;(2)the thyroid cartilage; (3)the cricothyroid muscles;(4)the cricoid cartilage; (5)the isthmus of the thyroid gland, which lies in front of the second, third, and fourth rings of the trachea;


Dissection of the neck

(6)the inferior thyroid veins, which lie in front of the trachea; (7)the thyroideaima artery, which, when present, ascends from the brachiocephalic artery in front of the trachea to the isthmus of the thyroid gland.


Dissection of the neck

To assist you in identifying these structures, remove the pretracheal fascia between the infrahyoid muscles. Transect the sternohyoid muscle at its lower end and reflect it superiorly. Now transect the sternothyroid muscle near its lower end and reflect it superiorly to the oblique line on the thyroid cartilage. Identify the ansa cervicalis and its branches to the infrahyoid muscles.


Deep dissection of the neck

Deep Dissection of the Neck


Dissection of the neck

Thyroid Gland. Remove the anterior part of the capsule of the thyroidgl and formed from the pretracheal fascia and expose the isthmus of the thyroid gland. Clean the superior, middle, and inferior thyroid veins. Examine the trachea.


Dissection of the neck

Note that it recedes from the surface as it descends into the thorax. Follow the superior thyroid artery to the thyroid gland from its origin from the external carotid artery. Identify again and carefully clean the external laryngeal nerve that accompanies the artery and follow the nerve to the cricothyroid muscle, which it innervates.


Dissection of the neck

Identify and clean the inferior thyroid gland artery. At the upper border of the isthmus of the thyroid gland, identify and clean the levator glandulae thyroideae (if present), which connects the thyroid isthmus to the hyoid bone. When present, it usually lies to the left of the midline.


Dissection of the neck

Divide the isthmus of the thyroid gland vertically in the midline.Reflect the right and left lobes laterally and look for the four small, yellowish brown parathyroid glands, which measure about 5 mm in diameter. The glands are embedded in the posterior surface of the capsule of the thyroid gland.Note that the thyroid gland is bound down to the larynx by the pretracheal fascia.


Dissection of the neck

Clean the sides of the trachea and the esophagus and expose the recurrent larygeal nerve, which lies in the glove between them. Note the close relationship between the recurrent laryngeal nerve and the inferior thyroid artery.


Dissection of the neck

Common carotid artery. Remove the carotid sheath from the common carotid artery. Study the right common carotid artery and note that it arises from the brachiocaphalic artery behind the sternoclavicular joint.


Dissection of the neck

The left artery arises from the arch of the aorta in the superior mediastinum. The common carotid artery runs upward and backward through the neck, from the sternoclavicular joint to the upper border of the thyroid cartilage, where it divides into the external and internal carotid arteries.


Dissection of the neck

Examine the terminal part of the common carotid artery and beginning of the internal carotid artery for a localized dilatation, the carotid sinus. Note that the common carotid artery is embedded in the carotid sheath and that it is closely related to the internal jugular vein and the vagus nerve. Apart from the two terminal branches, the common carotid artery gives off no branches.


Dissection of the neck

External carotid artery. Displace the sternocleidomastoid muscle laterally and complete your examination and cleaning of the external carotid artery and its branches.


Dissection of the neck

The artery begins at the level of the upper border of the thyroid cartilage, and it terminates in the substance of the parotid gland, behind the neck of the mandible,by dividing into the superficial temporal and maxillary arteries. 


Dissection of the neck

As the external carotid artery ascends through the neck,it lies at first medial to the internal carotid artery, and then it passes backward and laterally. Examine the branches of the external carotid artery as follows:


1 the superior thyroid artery arises from the front of the external carotid artery near its origin

1. The superior thyroid artery arises from the front of the external carotid artery near its origin.


Dissection of the neck

2. The lingual artery arises from the anterior surface of the external carotid artery, opposite the tip of the greater cornu of the hyroid bone.


Dissection of the neck

3. The facial artery arises from the anterior surface of the external carotid artery, just above the level of the tip of the greater cornu of the thyroid bone.


Dissection of the neck

4. The occipital artery arises from the posterior surface of the external carotid artery, opposite the facial artery.


Dissection of the neck

5. The posterior auricular artery arises from the posterior surface of the external carotid artery, at the level of the upper border of the posterior belly of the digastric muscle.


Dissection of the neck

Vagus nerve. Trace the vagus nerve down to the root of the neck on both sides. Identify the right recurrent laryngeal nerve as it arises from the right vagus and follow it around the subclavian artery to reach the groove between the trachea and the esophagus. Identify the cardiac branches of the vagus nerve.


Dissection of the neck

Thoracic duct and right lymphatic duct.Carefully dissect out the terminal part of the thoracic duct on the left side of the esophagus. It lies behind the common carotid artery and the internal jugular vein and curves laterally and downward in front of the subclavian artery.


Dissection of the neck

Identify, if possible, the right lymphatic duct on the right side of the esophagus. Look for examples of the deep cervical lymph nodes embedded in the lateral part of the carotid sheath.


Dissection of the neck

Sympathetic trunk. Retract the common carotid artery laterally and clean the sympathetic trunk. Trace the trunk superiorly and inferiorly and identify the superior, middle, and inferior cervical ganglia.


Dissection of the neck

三、枕三角(肩胛舌骨肌斜方肌三角):

(一)境界:

位于胸锁乳突肌后缘、斜方肌前缘和肩胛舌骨肌下腹上缘之间。

(二)内容:

1.副神经:出颈静脉孔后、沿颈内静脉前外侧下行,经二腹肌

后腹深面,胸锁乳突肌上部前缘

穿入并发出分支支配该肌。


Dissection of the neck

  • 第八单元 颈部的浅层结构

  • 大纲要求

  • 概述

  • 表面解剖

  • 详细内容

  • 操作过程

  • 实习要点

  • 自我测试


  • Login