Muscles. Fascicle Orientation of Muscles. Chapter 10 Objectives: The Muscular System

Transcription

1 Chapter 10 Objectives: The Muscular System Learn major groupings of Skeletal muscles Understand how movements occur at joints Learn the origin, insertion, function of some major muscles Muscles about 600 human skeletal muscles constitute about half of our body weight three kinds of muscle tissue skeletal, cardiac, smooth specialized for one major purpose converting the chemical energy in ATP into the mechanical energy of motion myology the study of the muscular system Functions? Movement, stability, control of body openings, heat production Fascicle Orientation of Muscles Attachment Sites: Origin and Insertion Parallel T riangular Unipennate Bipennate Multipennate Fusiform Tendon Circular Belly Tendon Direct & indirect muscle attachment Origin = bone that does not move when muscle shortens (normally proximal) Insertion = movable bone (usually distal) Most movements = several muscles working Most muscles are arranged in opposing pairs at joints prime mover or agonist - contracts to cause desired action antagonist stretches and yields to prime mover synergists & fixators stabilize joints & origin of the prime mover Hints: Names of Skeletal Muscle Direction fibers run, size, shape, action, number of origins/locations E.G. - Direction: Rectus femoris - Size: gluteus maximus - Shape: serratus anterior - Action: carpi radialis - Number of origins: Triceps brachii

2 Muscles in Facial Expression Superficial Deep Muscles in Facial Expression Galea aponeurotica Frontalis Galea aponeurotica Frontalis Corrugator supercilii Temporalis Corrugator supercilii Orbicularis oculi Orbicularis oculi Occipitalis Nasalis Levator labii superioris Zygomaticus minor Nasalis Levator anguli oris Zygomatic arch Levator labii superioris Zygomaticus minor Zygomaticus major Risorius Masseter Buccinator Zygomaticus major Modiolus Depressor anguli oris Orbicularis oris Masseter Orbicularis oris Depressor labii inferioris Mentalis Platysma Modiolus Risorius Within superficial fascia Arise (origin)??? Insetion? Mentalis Depressor labii inferioris Depressor anguli oris Buccinator Muscles that Move the Mandible Masseter, temporalis, & pterygoids Origin=skull Insert = mandible Masseter elevate the mandible (biting) Temporalis retracts & elevates Pterygoid muscles Muscles of Chewing and Swallowing extrinsic muscles of the tongue intrinsic muscles of tongue vertical, transverse, and longitudinal fascicles Palatoglossus Styloglossus Inferior longitudinal muscle of tongue Genioglossus Mylohyoid Geniohyoid Larynx Trachea Stylohyoid Posterior belly of digastric Superior pharyngeal constrictor Middle pharyngeal constrictor Hyoglossus Hyoid bone Styloid process Mastoid process Inferior pharyngeal constrictor Esophagus

3 Muscles that Move the Head Muscles Used in Breathing Digastric Sternocleidomastoid muscle arises from sternum & clavicle & inserts onto mastoid process contraction of one, laterally flexes the neck and rotates face in opposite direction Scalenes Cervical Vert. to Ribs 1 & Quadratus lumborum fills in space between 12th rib & iliac crest to create posterior body wall Inspiration: thoracic cavity increases in size external intercostals lift ribs diaphragm contracts: dome is flattened During expiration, thoracic cavity decreases in size internal intercostal mm used in forced expiration Muscles of the Anterior Abdominal Wall four pairs of sheetlike muscles external abdominal internal abdominal transverse abdominal rectus abdominis External abdominal Internal abdominal Transverse abdominal Rectus abdominis Rectus sheath Peritoneum Posterior Anterior Muscles of Abdominal Wall 4 layers of muscle in the abdominal wall Inguinal canal = passageway from pelvis Inguinal ring = opening Subcutaneous fat Aponeurosis Linea alba Skin Figure Superficial Muscles of Back Superficial Deep Semispinalis capitis Sternocleidomastoid Splenius capitis Trapezius Levator scapulae Rhomboideus minor Rhomboideus major Supraspinatus Deep Muscles of the Back erector spinae: iliocostalis, longissimus, spinalis from cranium to sacrum extension and lateral flexion of vertebral column Superior nuchal line Longissimus capitis Splenius capitis Serratus posterior superior Splenius cervicis Erector spinae: Iliocostalis Longissimus Semispinalis capitis Semispinalis cervicis Semispinalis thoracis Erector spinae Serratus anterior Spinalis Serratus posterior inferior Latissimus dorsi External abdominal Thoracolumbar fascia External abdominal Internal abdominal Serratus posterior inferior Internal abdominal External abdominal Multifidus Quadratus lumborum Gluteus medius Gluteus minimus Gluteus maximus Lateral rotators Figure

4 Anterior Group of Muscles of Pectoral Girdle Male Ischiocavernosus Ischiocavernosus Female pectoralis minor ribs 3-5 to scapula serratus anterior ribs 1-9 to scapula abducts and rotates or depresses scapula Bulbospongiosus Bulbospongiosus Urethra Vagina Copyright The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Anus Subclavius Gluteus maximus Gluteus maximus Pectoralis minor (a) Superficial perineal space, inferior view Pectoralis minor Internal intercostals Serratus anterior External intercostals Rectus abdominis three muscles found just deep to the skin ischiocavernosus bulbospongiosus Rectus sheath Internal abdominal Inguinal ligament (b) Deep External abdominal Internal abdominal Posterior wall of rectus sheath (rectus abdominis removed) Transverse abdominal Figure 10.15b Anterior thoracic muscles Subclavius extends from 1st rib to clavicle Pectoralis minor extends from ribs to coracoid process Serratus anterior extends from ribs to inner surface of scapula Stabilizing the Pectoral Girdle Stabilizing the Pectoral Girdle Posterior thoracic muscle Trapezius extends from skull & vertebrae to clavicle & scapula Levator scapulae extends from cervical vertebrae to scapula Rhomboideus extends from thoracic vertebrae to vertebral border of scapula (major and minor) Muscles Acting on Arm nine muscles cross the shoulder joint and insert on humerus two are axial muscles because they originate on axial skeleton 1. pectoralis major 2. latissimus dorsi Medial head Biceps brachii Brachialis Clavicle Sternum Pectoralis major Coracobrachialis Supraspinatus Spine of scapula Greater tubercle of humerus Humerus Latissimus dorsi Muscles Acting on Arm 7 scapular muscles originate on scapula 1. deltoid rotates and abducts arm intramuscular injection site 2. teres major extension and medial rotation of humerus 3. coracobrachialis flexes and medially rotates arm 4 7 remaining four form the rotator cuff Medial head Biceps brachii Brachialis Figure 10.24a (a) Anterior view Clavicle Sternum Pectoralis major Coracobrachialis Supraspinatus Spine of scapula Greater tubercle of humerus Humerus Latissimus dorsi (a) Anterior view (b) Posterior view Figure 10.24a Figure 10.24b Figure 10.24b (b) Posterior view

5 The McGraw-Hill Companies, Inc./Rebecca Gray, photographer/don Kincaid, dissections Rotator Cuff Muscles tendons of the remaining four scapular muscles form the rotator cuff Rotator Cuff Muscles Anterior Posterior SITS muscles for the first letter of their names supraspinatus infraspinatus teres minor subscapularis Rotator cuff (SITS) muscles: Supraspinatus Subscapularis Clavicle Acromion Coracoid process Glenoid cavity Inferior angle Figure Anterior View of Cadaver Chest Back Muscles of Cadaver Copyright The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Levator scapulae Rhomboideus minor Rhomboideus major Pectoralis major Biceps brachii: Short head Serratus anterior External abdominal Medial border of scapula Latissimus dorsi (a) Anterior view (b) Posterior view Figure 10.25b s of the Forearm (elbow) Cross anterior surface of elbow joint & form flexor muscle compartment Biceps brachii scapula to radial tuberosity flexes shoulder & elbow & supinates hand Brachialis humerus to ulna s of the Forearm (elbow) Cross posterior surface of elbow joint & forms extensor muscle compartment Triceps brachii long head arises scapula medial & lateral heads from humerus inserts on ulna

6 Common flexor tendon Cross Section of Upper Limb Pectoralis major Biceps brachii Triceps brachii (a) (b) (c) (a) Biceps brachii: Short head Coracobrachialis Humerus Latissimus dorsi tendon Anterior view Brachialis Common flexor tendon Pronator teres Aponeurosis of biceps brachii carpi radialis Palmaris Supinator Interosseous membrane profundus carpi ulnaris Anterior Lateral Medial Biceps brachii carpi radialis and pollicis pollicis Brachialis Posterior Key Anterior (flexor) compartment, superficial Anterior (flexor) compartment, deep (b) Posterior (extensor) compartment Medial head retinaculum Palmar aponeurosis tendons tendons Other muscles Pronator teres profundus tendons profundus tendons Supinator Radius carpi radialis carpi radialis carpi radialis Palmaris pollicis carpi ulnaris (a) Superficial flexors (b) Intermediate flexor (c) Deep flexors digiti minimi carpi ulnaris (c) profundus Ulna Anconeus Figure Intrinsic Hand Muscles Posterior view Triceps brachii Anconeus carpi ulnaris carpi radialis carpi radialis Olecranon Anconeus Supinator Abductor pollicis Retinaculum dorsal interosseous muscles palmar interosseous muscles lumbricals Tendon sheath First dorsal interosseous carpi ulnaris digiti minimi Tendon of extensor indicis Tendons of extensor Abductor pollicis pollicis pollicis Tendons of extensor carpi radialis and pollicis indicis pollicis Tendon of flexor profundus Tendon of flexor Lumbricals Opponens digiti minimi digiti minimi Abductor digiti minimi retinaculum pollicis Tendon of flexor pollicis pollicis Abductor pollicis Opponens pollicis Tendons of: Tendons of: carpi ulnaris Abductor pollicis carpi radialis Palmaris pollicis (a) Superficial extensors (b) Deep extensors (a) Palmar aspect, superficial Muscles Acting on the Hip and Femur anterior muscles of the hip iliacus flexes thigh at hip iliacus portion arises from iliac crest and fossa psoas major flexes thigh at hip arises from lumbar vertebrae they share a common tendon on the femur Iliopsoas: Iliacus Psoas major Pectineus magnus Insertion of gracilis on tibia Figure Piriformis Obturator externus Posterior Muscles Acting on Hip and Femur lateral and posterior muscles of the hip tensor fasciae latae gluteus maximus prime hip extensor gluteus medius and minimus abduct and medially rotate thigh 6 under gluteus minimus!! Iliac crest Gluteus medius Sacrum Gluteus maximus Coccyx Ischial tuberosity Superficial Deep Gluteus minimus Lateral rotators: Piriformis Gemellus superior Obturator internus Obturator externus Gemellus inferior Quadratus femoris

7 Muscles Acting on Hip and Femur medial (adductor) compartment of thigh primary adductors of the thigh adductor adductor magnus gracilis pectineus Iliopsoas: Iliacus Psoas major Pectineus magnus Piriformis Obturator externus Muscles Crossing the Hip Joint muscles bring legs together cross hip joint medially Pulled groin muscle Insertion of gracilis on tibia Figure Muscles Acting on the Knee and Leg Anterior Thigh Cadaver Muscles Copyright The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Iliac crest Lateral Medial Quadriceps femoris has 4 heads 1. Rectus femoris crosses hip (biggie) 2. Vastus lateralis 3. Vastus intermedius 4. Vastus medialus Iliopsoas: Iliacus Psoas major Anterior superior iliac spine Tensor fasciae latae Iliotibial band L5 Medial compartment: magnus Pectineus Anterior compartment: Sartorius Quadriceps femoris: Vastus intermedius Rectus femoris Vastus lateralis Vastus medialis Tensor fasciae latae Iliopsoas Sartorius Iliotibial band Quadriceps femoris: Rectus femoris Vastus lateralis Vastus medialis Femoral vein Femoral artery Pectineus Sartorius!!!!!! Quadriceps femoris tendont Patella Patellar ligament Quadriceps tendon Patella Figure (a) Superficial (b) Deep The McGraw-Hill Companies, Inc./Rebecca Gray, photographer/don Kincaid, dissections Figure Muscles Acting on the Knee and Leg Anterior Compartment of Leg Patella posterior (flexor) compartment of the thigh hamstring muscles from lateral to medial; biceps femoris semitendinosus semimembranosus Gluteus medius Gluteus maximus magnus Iliotibial band Vastus lateralis Hamstring group: Biceps femoris Short head Semitendinosus Semimembranosus Patellar ligament retinacula Tibia Gastrocnemius Soleus Tibialis anterior Tibialis anterior hallucis hallucis tertius (a) (b) (c) (d) Figure

8 Posterior Compartment of Leg Superficial Group Intrinsic Muscles of Foot Gastrocnemius: Plantaris Popliteus Heads of gastrocnemius digiti minimi Abductor digiti minimi Abductor hallucis Quadratus plantae Lumbricals hallucis tendon tendon Abductor hallucis Medial head Tendon of plantaris Soleus Plantar aponeurosis Calcaneus (a) Layer 1, plantar view (b) Layer 2, plantar view Gastrocnemius Tendon of gastrocnemius Calcaneal tendon hallucis digiti minimi hallucis Plantar hallucis interosseous hallucis tendon Dorsal interosseous (a) Calcaneus (b) Quadratus plantae Abductor hallucis tendon (c) Layer 3, plantar view (d) Layer 4, plantar view (e) Layer 4, dorsal view