Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Chapter 11, Part 2 Muscles of the head and Neck Fig. 11.2b © The McGraw-Hill Companies, Inc./Photos and Dissections by Christine Eckel Copyright © McGraw-Hill Education. Permission required for reproduction or display. Fig. 11.2b Epicranial aponeurosis Epicranius Frontal belly of occipitofrontalis Occipital belly of occipitofrontalis Orbicularis oculi Levator labii superioris Zygomaticus minor Levator anguli oris Zygomaticus major Buccinator Orbicularis oris Sternocleidomastoid Mentalis Depressor labii inferioris Depressor anguli oris Platysma © The McGraw-Hill Companies, Inc./Photos and Dissections by Christine Eckel Copyright © McGraw-Hill Education. Permission required for reproduction or display. Fig. 11.4 Extrinsic Eye Muscles (a) Lateral view, right eye Superior oblique Frontal bone Superior rectus Common tendinous ring Trochlea Optic nerve Lateral rectus Orbicularis oculi • AKA extraocular muscles • called extrinsic because originate in orbit and insert into sclera of eye • Move the eyes • Rectus eye muscles originate from common tendinous ring Inferior rectus Maxilla Inferior oblique Copyright © McGraw-Hill Education. Permission required for reproduction or display. (a) Lateral view, right eye Extrinsic Eye Muscles • Lateral rectus • attaches to anterolateral surface of eye • pulls eye laterally (toward ear) Superior rectus • Inferior rectus • attaches to anteroinferior surface of eye • pulls eye down and medially (look at tip of nose) Lateral rectus Inferior rectus • Superior rectus • attaches to anterosuperior surface of eye • pulls eye up and medially (look at procerus muscle) Copyright © McGraw-Hill Education. Permission required for reproduction or display. Fig. 11.4 (b) Medial view, right eye Extrinsic Eye Muscles • Medial rectus • attaches to anteromedial surface of eye • pulls eye medially (toward bridge of nose) Superior rectus Medial rectus Optic nerve Common tendinous ring Inferior rectus Fig. 11.4 (a) Lateral view, right eye Extrinsic Eye Muscles Superior oblique Trochlea • Oblique eye muscles • originate from within the orbit • inserts on posterolateral part of eye • Superior oblique • hooks through trochlea • inserts on posterior superior part of eye • pulls back of eye up (eye looks down) • Inferior oblique • inserts on posterior inferior part of eye • pulls back of eye down (eye looks up) Inferior oblique Copyright © McGraw-Hill Education. Permission required for reproduction or display. Fig. 11.4 (b) Medial view, right eye (a) Lateral view, right eye Superior oblique Frontal bone Superior rectus Common tendinous ring Trochlea Orbicularis oculi Trochlea Superior rectus Superior oblique Medial rectus Optic nerve Optic nerve Lateral rectus Inferior rectus Inferior oblique Common tendinous ring Inferior rectus Maxilla Inferior oblique Trochlea Superior rectus Sagittal axis Coronal axis Superior oblique Lateral rectus Optic canal Common tendinous ring Inferior oblique Inferior rectus Medial rectus (c) Anterior view of right orbit, eye removed Trochlea Center of eye Inferior oblique Superior oblique Medial rectus Inferior Lateral (d) Superior view Superior rectus rectus rectus Copyright © McGraw-Hill Education. Permission required for reproduction or display. Fig. 11.5 Muscles of Mastication (superficial) Temporalis • Buccinator is deep to masseter • prevents “chipmunk cheeks” • Masseter connects zygomatic process to mandible • elevates and protracts mandible • most powerful chewing muscle • Orbicularis oris is ring around mouth • “puckers up” Buccinator Masseter Orbicularis oris (a) Superficial lateral view • Temporalis extends from temporal lines on parietal and frontal bones to coronoid process of mandible (deep to zygomatic process) • elevates and retracts mandible Copyright © McGraw-Hill Education. Permission required for reproduction or display. Fig. 11.6 Muscles that Move the Tongue • Intrinsic muscles curl, squeeze and fold tongue • sit inside tongue • tongue acts like muscle, but actually isn’t • Extrinsic muscles have origin on other head and neck structures, insert on tongue Palatoglossus Styloid process Tongue Styloglossus Genioglossus Mandible (cut) Hyoid bone Hyoglossus • end in -glossus Right lateral view Thyroid cartilage Fig. 11.6 Muscles that Move the Tongue (extrinsic) • genioglossus muscles (left/right) • originate on mandible • protract tongue Styloid process Tongue Genioglossus Mandible (cut) Hyoid bone Styloglossus Thyroid cartilage Right lateral view Fig. 11.6 Muscles that Move the Tongue (extrinsic) • genioglossus muscles (left/right) • originate on mandible • protract tongue Styloid process Tongue Styloglossus Genioglossus Mandible (cut) Hyoid bone • styloglossus muscles (left/right) • originate on styloid process of temporal bone • elevate and retract tongue Thyroid cartilage Right lateral view Fig. 11.6 Muscles that Move the Tongue (extrinsic) Palatoglossus • hyoglossus muscles (left/right) • originate on hyoid bone • insert on sides of tonue • depress and retract tongue Tongue Styloglossus Genioglossus Mandible (cut) Hyoid bone Hyoglossus • palatoglossus muscles (left/right) • originate on soft palate • elevate posterior portion of tongue Thyroid cartilage Right lateral view Fig. 11.6 Muscles of the Pharynx • pharynx is funnel-shaped tube Styloid behind and below mouth and nose process • pharyngeal constrictor muscles contract sequentially to swallow food pharyngeal Tongue Mandible (cut) constrictor muscles Hyoid bone Thyroid cartilage Right lateral view Fig. 11.6 Muscles of the Anterior Neck • Suprahyoid muscles are above the hyoid bone • elevate hyoid during swallowing or speaking • Stylohyoid muscle • originates on styloid process of temporal bone • inserts on hyoid • elevates hyoid, elongates oral cavity during swallowing • Geniohyoid muscle • originates on mental spines of mandible • inserts on hyoid • elevates hyoid Styloid process Tongue Stylohyoid Mandible (cut) Geniohyoid Hyoid bone Thyroid cartilage Right lateral view Fig. 11.8 Superficial Anterior Neck • Digastric: two bellies • anterior belly from mental protuberance to hyoid • posterior belly from hyoid to mastoid portion of temporal bone • depresses mandible, elevates hyoid Digastric: Anterior belly Posterior belly Sternocleidomastoid Trapezius Fig. 11.8 Anterior Neck • Mylohyoid • muscular floor of mouth • elevates hyoid and raises floor of mouth Superficial Mylohyoid Stylohyoid Fig. 11.8 Superficial Anterior Neck • Omohyoid • • • • • two thin bellies lateral to sternohyoid originates at superior border of scapula inserts on hyoid Omohyoid depresses hyoid Sternohyoid • Sternohyoid • originates at sternum • inserts on hyoid • depresses hyoid Fig. 11.8 Superficial Deep Anterior Neck • Thyrohyoid • Originates at thyroid cartilage • Inserts at hyoid • Depresses hyoid and elevates thyroid cartilage to close off larynx during swallowing • Sternothyroid • • • • deep to sternohyoid originates at sternum inserts at cartilage of thyroid depresses thyroid cartilage to return it to position after swallowing Thyroohyoid Sternothyroid Fig. 11.9 Stylohyoid Posterior belly of digastric Semispinalis capitis Splenius capitis Levator scapulae Mylohyoid Anterior belly of digastric Thyrohyoid Inferior constrictor Sternothyroid Superior belly of omohyoid Sternohyoid Sternocleidomastoid Scalene muscles Trapezius Inferior belly of omohyoid Platysma (cut) Anterolateral view Copyright © McGraw-Hill Education. Permission required for reproduction or display. Fig. 11.9 Muscles that Move the Head and Neck • Anterolateral neck muscles flex the neck • Sternocleidomastoid • Originates on sternum and clavicle • Inserts on mastoid process of temporal bone • Contraction of both flexes the neck • Contraction of one rotates head to opposite side and laterally flexes neck Sternocleidomastoid Scalene muscles Trapezius Inferior belly of omohyoid Anterolateral view Platysma (cut) Copyright © McGraw-Hill Education. Permission required for reproduction or display. Fig. 11.9 Muscles that Move the Head and Neck • Anterolateral neck muscles flex the neck • Scalene muscles (anterior, middle, and posterior) • Originate from transverse processes of C2 to C7 • Insert onto ribs 1 and 2 • Elevate ribs 1 and 2 during inhalation Sternocleidomastoid Scalene muscles Trapezius Inferior belly of omohyoid Anterolateral view Platysma (cut) Copyright © McGraw-Hill Education. Permission required for reproduction or display. Fig. 11.9 Muscles that Move the Head and Neck • Trapezius • Superior fibers support neck • Originate on occipital protuberance (occipital bone) and spinous processes of C7 to T12 • Insert on clavicle and scapula • Pulls down on back of head Sternocleidomastoid Scalene muscles Trapezius Inferior belly of omohyoid Anterolateral view Platysma (cut) Fig. 11.11 Muscles of the Vertebral Column Deeper Deep Longissimus capitis Splenius capitis Serratus posterior superior External intercostals Splenius cervicis Iliocostalis group Longissimus group Erector spinae Spinalis group • Complex origins and insertions • Extensive overlap • Covered by superficial back muscles (trapezius and lattisimus dorsi) Semispinalis capitis Semispinalis cervicis Transversospinalis Semispinalis thoracis Serratus posterior inferior Multifidus Internal oblique Quadratus lumborum External oblique (cut) Posterior view Fig. 11.11 Muscles of the Vertebral Column • Erector spinae • group of muscles that maintain posture • iliocostalis group • most laterally placed • longissimus group Erector spinae Deep Iliocostalis group Longissimus group Spinalis group • inserts on transverse processes of vertebrae • spinalis group • most medially placed • insert on spinous processes of vertebrae Posterior view Fig. 11.11 Muscles of the Vertebral Column • Transversospinalis • connect and stabilize vertebrae • includes semispinalis capitis, semispinalis cervicis • semispinalis thoracis extends and laterally flexes vertebral column • multifidus extends and rotates vertebral column • rotatores thoracis extends and rotates vertebral column Posterior view Deeper Semispinalis capitis Semispinalis cervicis TransversoSemispinalis spinalis thoracis Multifidus Rotatores thoracis Transverse process of vertebra Spinous process of vertebra Fig. 11.11 Muscles of the Vertebral Column • Quadratus lumborum • located primarily in lumbar region • bilateral contraction extends vertebral column • unilateral contraction flexes vertebral column laterally Deeper Quadratus lumborum Posterior view Fig. 11.13 Muscles of Respiration • Muscles contract to increase volume of lungs, drawing air in (inhalation) • On exhalation, most muscles relax, some contract to decrease volume of lungs, forcing air out • respiration muscles are on anterior and posterior surfaces of thorax, deep to trapezius and latissimus dorsi, superficial to erector spinae muscles Scalene muscles External intercostals Internal intercostals Transversus thoracis Diaphragm (a) Anterior view Fig. 11.13 Muscles of Respiration Scalene muscles • external intercostals extend from superior rib to adjacent inferior rib • lift rib on inhalation External intercostals Internal intercostals • internal intercostals lie deep to external intercostals Transversus thoracis • fibers at right angles to external intercostals • depress ribs on exhalation Diaphragm (a) Anterior view Fig. 11.13 Muscles of Respiration • serratus posterior superior attaches to ribs 2-5; elevates them in inhalation • serratus posterior inferior attaches to ribs 8-12; depresses them during exhalation Fig. 11.13 Muscles of Respiration • transverse thoracis extends across inner surface of rib cage, inserts on ribs 2-6 Scalene muscles • depresses ribs Transversus thoracis Diaphragm (a) Anterior view (a) Interior view Fig. 11.13 Muscles of Respiration • diaphragm is sheet of muscle that separates thoracic cavity from abdominal cavity • aponeurosis in center is insertion point • contraction of diaphragm pulls diaphragm down, increasing size of thoracic cavity Diaphragm (a) Anterior view Fig. 11.13 Muscles of Respiration • diaphragm is sheet of muscle that separates thoracic cavity from abdominal cavity • aponeurosis in center is insertion point • contraction of diaphragm pulls diaphragm down, increasing size of thoracic cavity Fig. 11.13 Muscles of Respiration • diaphragm is sheet of muscle that separates thoracic cavity from abdominal cavity • aponeurosis in center is insertion point (central tendon) • contraction of diaphragm pulls diaphragm down, increasing size of thoracic cavity (a) Diaphragm, inferior view Sternum Xiphoid process Costal cartilage Central tendon of diaphragm Caval opening Aortic opening (hiatus) 12th rib Right crus Esophageal opening Left crus L2 L3 L4 Quadratus lumborum muscle (cut) Psoas major muscle (cut) Fig. 11.13 Muscles of the Abdominal Wall • muscles compact and hold in the abdominal organs • work together to flex and stabilize vertebral column • unilateral contraction laterally flexes vertebral column Fig. 11.13 Muscles of the Abdominal Wall • rectus abdominis • long, runs vertically entire length of abdominal wall from pubis (origin) to sternum (insertion) • four segments created by three tendinous intersections (form “six pack”) • enclosed in rectus sheath made by • aponeurosis of external oblique • internal oblique • transversus obdominis • Medial border of rectus sheaths is fibrous strip called linea alba Linea alba Rectus sheath Tendinous intersection Rectus abdominis Muscles of the Abdominal Wall • external oblique • most superficial of abdominal muscles • two groups of muscles connected by Transversus abdominis aponeurosis Internal obliques • inguinal ligament extends from External obliques anterior superior iliac spine to public tubercle along bottom of aponeurosis • fibers run from superior lateral to inferior medial Fig. 11.13 Muscles of the Abdominal Wall • internal oblique • deep to external oblique • forms aponeurosis medially • fibers run from inferior lateral to superior medial • rotates vertebral column • transversus obdominis • deep to internal oblique • fibers run laterally Transversus abdominis Internal obliques External obliques Fig. 11.13 Muscles of the Pelvic Floor • Pelvic diaphragm = 3 layers of muscles and fasciae • Extends from ischium and pubis to sacrum and coccyx • Support pelvic viscera