HAN 200 Chapter 10

Movements of the Thigh (Abductors and External (lateral) rotators)

**Abductors** Gluteus medius (also medially rotates thigh) Gluteus minimus (also medially rotates thigh) Gluteus maximus (also laterally rotates thigh) **External (lateral) rotators** 1.Piriformis 2.Obturator externus 3. Obturator internus 4/5. Gemellus (superior & inferior) 6. Quadratus femoris

Muscle of the Forearm: Posterior Compartment

**Extensors** -Extensors carpi radialis longus and brevis (wrist extension) -Extensor digitorum (finger extension) -Extensor carpi ulnaris (wrist extension) -Extensor pollicis brevis and longus (thumb extension) -Extensor indicis (index fingers) -Abductor pollicis longues- (thumb abduction)

Muscles of the Abdominal Wall

**Four paired muscles** 1) rectus abdominis 2) External obliques (most superficial) 3) Internal obliques 4) Transversus abdominis (deepest)

Muscles of the Leg: Movements

**Leg muscles produce the following movements: ** 1)Ankle-dorsiflexion and plantar flexion 2)Intertarsal joints: inversion and eversion of the foot 3)Toes: flexion and extension

Muscles of the Posterior Compartment of the Leg

**Plantar flex ankle** -Gastrocnemius -Soleus -Plantaris -Popliteus -Flexor digitorum longus (Flex toes) -Flexor hallucis longus (flex great toe) -Tibialis posterior

Intrinsic Muscles of the Hand

**Small weak muscles** 1)Thenar eminence (ball of thumb): produce opposition- move thumb toward little finger 2)Hypothenar eminence (ball of the little finger)- Each of above groups has flexor, abductor, and opponens muscle 3)Midpalmar muscles- lumbricals and interossei -Abduct and adduct fingers 4)Lie entirely within palm of hand

Classifications of Levers (LFE, ELF, LEF)

**Three types of levers based on positions of the fulcrum, the effort and load** 1) First-Class Levers: fulcrum is between the effort and the load 2) Second-Class Lever: the load is between fulcrum and effort (Ex: Wheelbarrow) 3)Third-Class Lever: The effort is between the fulcrum and the load (Example: pair of forceps)

Muscle Crossing the Elbow Joint (posterior)

- Posterior extensor muscles -Triceps brachii- (3 heads) prime mover of elbow extension -Anconeus- weak synergist

Muscle Crossing the Elbow Joint (Anterior)

-Anterior flexor muscles -Brachialis and biceps brachii (2 heads)- chief forearm flexors (chin ups vs pull up) -Brachioradialis: synergist and stabilizer

Major Skeletal muscles of the Body #2 (To learn)

-Be aware of information learned from muscle name -Read description; identify on figure; relate location and description -Relate attachments to actions -Act out movements on yourself

Muscles of the Forearm: Anterior Compartment

-Flexors -Flexor carpi radialis (Wrist flexion) -Palmaris longus -Flexor carpi ulnaris (Wrist flexion) -Flexor digitorum superficialis and flexor digitorum profundus (finger flexion) - Flexor pollicis longus (thumb flexion)

Plantar Muscles

-Four Layers of plantar muscles -Superficial layer -Flexor digitorum brevis -Abductor hallucis -Abductor digiti minimi -Second Layer -Flexor accessorius -Lumbricals

Movements of the Thigh (Thigh(Hip) extensors)

-Hamstring muscles: prime movers of extension -Biceps femoris (lateral hamstring) -Semitendinosus (medial hamstring) -Semimembranosus (medial hamstring) Gluteus Maximus: assists hamstrings in forceful thigh extension

Intrinsic Muscles of the Foot

-Help flex, extend, abduct, and adduct toes -Support arches of foot; some leg tendons assist -Extensor digitorum brevis: dorsal foot muscle; helps extend toes

Muscle Mechanics: Lever Systems

-Levers allow given effort to move heavier load; move load farther and faster -Components of lever system 1) Lever: rigid bar (bone) that moves on a fixed point called fulcrum (joint) 2) Effort: force (supplied by muscle contraction) applied to lever to move resistance (load) 3) Load: resistance (bone+tissue+any added weight) moved by the effort

Muscle of the Forearm

-Pronator teres and pronator quadratus pronate forearm -Supinator: synergist with biceps brachii in forearm supination

Muscle Crossing the shoulder Joint #2

-Rotator cuff muscles act as synergists and fixators; originate on scapula; reinforce shoulder capsule; prevent dislocation 1) Supraspinatus: assists deltoid in abd 2) Infraspinatus: shoulder external rot 3) Teres minor: shoulder external rotation 4) Subscapularis: shoulder internal rotation

Movements of the Thigh( hip joint)

-Thigh flexors pass in front of hip joint -lliopsoas(iliacus and psoas major)- prime mover of flexion -Tensor fasciae latae -Rectus femoris (hip flexion) -Assisted by medial adductors (groin) and sartorius (cross leg)

Muscles of Tongue Movement

-Three muscles anchor and move tongue 1) Genioglossus 2) Hyoglossus 3) Styloglossus

Muscles Crossing the shoulder Joint

-Three prime movers of arm 1)Pectoralis major: adduction&flexion 2) Latissimus dorsi: adduction&extension 3) Deltoid: anterior fibers- flexion, middle fiber-abduction and posterior fibers- extension

Muscle of the Anterior Compartment of the Leg

-primary toe extensors and ankle dorsiflexors -Tibialis anterior (dorsiflexes foot) -Extensor digitorum longus (extends toes) -Extensor hallucis longus (Extends great toe)

Major Skeletal Muscles of the Body

1) >600 in body; grouped by function and location 2)Information for each muscle -shape -Location relative to other muscles -Origin and insertion- usually a joint between origin and insertion -Actions- insertion moves toward origin -Innervation-name of major nerve that supplies muscle

Arrangement of Fascicles (circular, convergent, parallel, fusiform and pennate)

1) Circular: Fascicles arranged in concentric rings (ex: orbicularis oris, orbicularis oculi) 2) Convergent: Broad origin; fascicles converge toward single tendon insertion (Ex: pectoralis major) 3) Parallel: Fascicles parallel to long axis of straplike muscle (ex: sartorius) 4) Fusiform: Spindle-shaped muscle with parallel fibers (Ex: Biceps brachii) 5) Pennate: Short fascicles attach obliquely to central tendon running length of the muscle (ex: rectus femoris)

Muscles of Facial Expression&MM of Mastication

1) MM of Facial Expression - Zygomaticus: smile - Risorius: grin -Orbicular Oculi: closed eyelid -Orbicularis Oris: pucker lips -Platysma: pulls corners of mouth down 2)MM for chewing -Temporalis -Masseter -Buccinator

Levers: Power versus speed

1) Mechanical advantage: (power level)- load close to fulcrum; effort far from fulcrum - Small effort can move large load 2)Mechanical disadvantage: (speed lever)-load far from fulcrum; effort close to fulcrum - Load moved rapidly over large distance; wide range of motion

Superficial Muscles of The Thorax

1) Most-extrinsic shoulder muscles -Act in combination to fix shoulder girdle (mostly scapula); move it to increase range of arm movements -Scapula actions: elevation, depression, rotation, protraction, and retraction 2) Two groups of muscles: anterior and posterior 3) Muscles of anterior thorax -Pectoralis minor: protraction& downward rotation of scapula -Serratus anterior (saw tooth): protraction -Boxing muscle -Subclavius: stabilizes pectoral girdle

Naming Skeletal Muscles

1) Muscle Location: bone or body region with which muscle associated 2) Muscle shape: ex) Deltoid muscle (Deltoid=triangle) 3) Muscle size- (ex: Maximus (largest), minimus (smallest), longus (long) 4) The direction of muscle fibers or fascicles - (Ex: Rectus (fibers run straight), transversus (Fibers run at right angles), and oblique(fibers run at angles to the imaginary defined axis) 5) Number of origins- Ex: biceps (2 origins) and triceps (3 origins) 6)Location of attachments: named according to point of origin and insertion (origin named first) -sternocleidomastoid 7) Muscle action- named for action they produce, ex) flexor or extensor - Several criteria can be combined, ex: extensor carpi radialis longus

Actions and Interactions of Skeletal Muscles

1) Muscles can only pull; never push 2) What one muscle group "does," another "undoes" 3) Agonist: primary mover 4) Antagonist: opposes or reverses particular movement

Muscles of the Pelvic Floor

1) Pelvic Floor (pelvic diaphragm): composed of two paired muscles which are Levator ani and Coccygenus - Floor of Core Muscles/supports pelvic organs 2)Urogenital diaphragm: contains external urethral sphincter (voluntary control of urination)

Superficial Muscles of the posterior thorax

1) Posterior extrinsic shoulder muscles: Trapezius -Upper trapezius: elevation of scap (Shrug) -Middle trapezius: retraction of scap -Lower trapezius: depression of scap -Levator scapulae -Rhomboids (major and minor)-retraction&downward rotation

Muscles of the Thigh that Move the Knee joint

1) Quadriceps femoris (4 muscles) -Sole extensor of knee (anterior muscle) -Recuts femoris -Vastus lateralis -Vastus medialis -Vastus intermedius 2) Hamstring muscles- flex knee (post mm) -Biceps femoris -Semitendinosus -Semimembranosus

Muscles of the Neck and Vertebral Column: Head movement

1) Sternocleidomastoid: major head flexor 2) Sternocleidomastoid and scalenes: lateral head movements 3)Splenius capitis and cervicis portions- head extension, rotation, and lateral bending 4) Semispinalis capitis: synergist with sternocleidomastoid

Skeletal Muscles: Functional Groups

1) Synergist helps prime movers -Adds extra force to same movement -Reduces undesirable or unnecessary movement 2) Fixator -Synergist that immobilizes bone or muscle's origin (rotator cuff and G-H joint) -Gives prime mover stable base on which to ace (Ex scap and G-H joint)

Pennate has three forms

1) Unipennate: fascicles attach only to one side of tendon (Ex: extensor digitorum longus) 2) Bipennate: fascicles insert from opposite sides of tendon (Ex: rectus femoris) 3) Multipennate: appears as feathers inserting into one tendon (Ex: deltoid)

Muscles of the Vertebral Column: Truck Extension

1)Deep (intrinsic) back muscles -Erector spinae (sacrospinalis) group: prime movers of back extension and lateral bending -Lliocostalis (most lateral) -Longissimus -Spinalis (most medial) 2) Semispinalis and quadratus lumborum: synergists in extension and rotation

How Skeletal Muscles Produce Movement: Fascicle Arrangement

1)Fascicle arrangement affects a muscle's power and range of motion 2)There are 5 patterns of fascicle arrangement: -Parallel -Fusiform -circular -triangular -pennate 3)Longer fibers produce greater range of motion 4) Power of a muscle depends on its cross-sectional area

Muscles Crossing Hip and Knee Joints

1)Movements at the hip include: flexion, extension, abduction, adduction, circumduction, and rotation 2)Most anterior muscles flex femur at hip, extend leg at knee (swing of walking) 3)Most posterior muscles extend thigh, flex leg (backswing of walking) 4)Medial muscles all adduct thigh 5)Lateral muscles abduct thigh

Deep Muscles of the Thorax: breathing

1)Muscle of respiration 2)External intercostals: more superficial muscles; elevate ribs for inspiration 3)Internal intercostals: deeper muscles; aid forced expiration 4)**Diapharagm:** -Partition between thoracic and abdominal cavities -Most important muscle in inspiration -Innervated by phrenic nerves - (upper cervical innervation)

The Muscular System

1)Muscle tissue- all contractile tissues - Skeletal, cardiac and smooth muscles 2)Focus on skeletal muscle -How muscles interact to-- a movement -Criteria for naming muscles -Principles of leverage

Muscle Mechanics: Importance of Fascicle Arrangement and Leverage

Additional forces contributing to muscle force and speed -Fascicle arrangement -Lever systems

Clicker Question #11: The rotator cuff muscles include the supraspinatus, infraspinatus, teres minor, and _________. A)Subscapularis B)Pectoralis major C)Teres major D)Deltoid

Answer: A) Subscapularis

Clicker Question #8: This muscle flexes the elbow and inserts on the ulnar A)Biceps brachi B)Brachialis C)Brachioradialis D)Coracobrachialis

Answer: B) Brachilalis

Clicker Question #7: The prime mover in abduction of the arm is the ______. A)triceps brachii B)deltoid C)biceps brachii D)latissimus dorsi

Answer: B) Deltoid

Clicker Question#9: The ______ is (are) the most important muscle(s) for inspiratory breathing. A)internal intercostals B)diaphragm C)scalenes D)rectus abdominis

Answer: B) diaphragm

Clicker Question #1: T tubules are an extension of the A)sarcomere B)sarcoplasmic reticulum C)sarcolemma D)endomysium

Answer: C) Sarcolemma

Clicker Question #4: The coracobrachialis muscle has its origin and insertion on what two bones? A) vertebral column and clavicle B) femur and tibia C) scapula and humerus D) trapezium and radius

Answer: C) Scapula and humerus

Clicker Question #2: The force exerted by a contracting muscle is? A)muscle summation B)muscle twitch C)muscle tension D)muscle load

Answer: C) muscle tension

Clicker Question #13: Which muscle is considered part of the hamstring group? A)Rectus femoris B)Gracilis C)Sartorius D)Biceps femoris E)Piriformis

Answer: D) Biceps femoris

Clicker Question #3:Which activity would be most dependent upon creatine? A)Tennis B)Soccer C)Jogging D)Diving

Answer: D) Diving

Clicker Question #14: This muscle inserts on the calcaneus A) Biceps femoris B) Tibialis anterior C) Tibialis posterior D) Gastrocnemius

Answer: D) Gastrocnemius

Clicker Question #5: When you bite down on an ice cube, this muscle strongly contracts. A)Lateral pterygoid B)Buccinator C)Hyoglossus D)Masseter

Answer: D) Masseter

Clicker Question#6: The ______ muscles are antagonistic to each other when moving the scapula forward and backward (protraction and retraction). A)pectoralis major and subclavius B)latissimus dorsi and rhomboid C)pectoralis minor and serratus anterior D)serratus anterior and trapezius

Answer: D) Serratus anterior and trapezius

Clicker Question #12: Which muscle group does not have an origin on the pelvic girdle? A)Hamstrings B)Gluteals C)Abdominals D)They all have origins on the pelvic girdle.

Answer: D) they all have origins on the pelvic girdle

Clicker Question#10: What arm muscle is the prime mover for this activity? A) biceps brachii B) latissimus dorsi C) triceps brachii D) flexor carpi radialis longus

C) Triceps brachii

Valsalva Maneuver

Increased intra abdominal pressure used during coughing, vomiting, sneezing, defecation and childbirth