MOVEMENT and SKELETAL MUSCLE

                                      

I  Movement

            A.  Requirements

            B.  Origin vs. Insertion

            C.  Muscle - Muscle Interactions: coordination and control

                        1.  opposing pairs

                                    a.  prime mover (agonist)

                                    b.  antagonist

                                    c.  synergists

                                                1.  fixators

            D.  Muscle - Bone Interactions:  work                   

                        1.  lever systems

                                    a.  lever = bone

                                    b.  fulcrum = joint

                                    c.  effort (power) = muscle

                                    d.  load

                        2.  first class levers

                                    a.  fulcrum between effort (force) and load (see-saw)                       

                        3.  second class levers

                                    a.  load between effort and fulcrum (wheelbarrow)               

                                    b.  strength, less speed and range of movement

                         4.  third class levers

                                    a.  effort between load and fulcrum

                                    b.  fast, large movements with little effort

                                    c.  most common in the body                                       

 

                          

 

  

When you finish this unit you should be able to: 

    -  list what is needed to provide movement of the bones

    -  define origin and insertion of a muscle

    -  identify the origin and insertion of a muscle when given the two points of attachment

    -  define the different roles a muscle can play:  agonist, antagonist, synergist

    -  identify role a muscle performs when given a particular movement

    -  list the components of a lever system in general and their counterparts in the body

    -  draw a 1st, 2nd, and 3rd class lever system

    -  compare the advantages and differences between the three lever systems

    -  identify an example of each class of lever systems in the body

   

                        

II   Muscle Capabilities 

             A.  Common to all muscle types

             B.  Differences between muscle types

 

 

III  Skeletal Muscle Structure

            A.  Organ

                 1.  skeletal muscle tissue

                          a. cell:  sarcolemma, striations, myofilaments

                         2.  connective tissue

                                    a.  endomysium (around fiber)

                                    b.  perimysium  (around fascicle)

                                    c.  epimysium  (around whole muscle)

                                    d.  deep fascia

                                    e.  tendon

                          3.  neural  tissue

                                    a.  neuromuscular junction

 

                                                              

 

                   B.  Fascicle structure and arrangement

                          1.  effects :  motion and power

                          2.  types

                                    a.  parallel

                                    b.  convergent

                                    c.  pennate   (uni-, bi-, multi-)

                                    d.  circular (sphincters)

 

 

When you finish this unit you should be able to:

    - identify skeletal, cardiac, and smooth muscle

            1)  by photo (or a slide ! )

            2) by structural characteristics

            3) by functional characteristics

    -  draw a muscle fiber and label its basic parts

    -  state the reason for the striated appearance, and the reason for nuclei at the periphery of the fiber

    -  identify and describe the organization of a muscle from fibers to fascicles to whole muscle including connective tissue wrappings

    -  explain how muscle can pull on bone when it never comes in direct contact with the insertion

    -  define neuromuscular junction and its location on a muscle fiber

    -  recognize and describe a parallel, a convergent, and a pennate arrangement of muscle fascicles

    -  discuss why a parallel arrangement is able to provide more movement

    -  discuss why a convergent arrangement provides less power and variety of movement

    -  discuss why a pennate arrangement provides less movement and more strength 

    -  describe sphincters and their roles in the body

 

 

IV  Abdominal Wall

            A.  Surface Markings

            B.  Muscles

                        1.  rectus abdominus

                                    a.  tendinous intersections

                             2.  external oblique

                        3.  internal oblique

                        4.  transversus abdominus

            C.  Aponeuroses and linea alba

 

V   Upper limb muscles

            A.  Scapular

                        1.  stabilize joint (rotator cuff)

                                    a.  all origins on scapula

                                    b.  all insertions on humerus

                                                1.  subscapularis

                                                2.  infraspinatus

                                                3.  teres minor

                                                4.  supraspinatus

                        2.  moor scapula

                                    a.  all origins on axial skeleton

                                    b.  all insertions on scapula

                                                1.  trapezius (3 areas)                                               

                                                2.  levator scapulae

                                                3.  rhomboids

                                                4.  pectoralis minor

                                                5.  serratus anterior

                        3.  move arm

                                    a.  all insertions on humerus

                                                1.  deltoids (3 areas)

                                                2.  pectoralis major

                                                3.  latissimus dorsi

                                                4.  teres major

                                                5.  coracobrachialis

            B.  Arm

                        1.  movement (at elbow) of forearm

                                    a.  anterior compartment; flexors; musculocutaneous nerve

                                                1.  biceps brachii

                                                2.  brachialis

                                                3.  (coracobrachialis)

                                    b.  posterior compartment; extensors; radial nerve

                                                1.  triceps brachii

            C.  Cubital fossa 

                    1.  structures

                                    a.  brachial artery ----> radial and ulnar artery

                                    b.  median nerve

                                    c.  bicipital aponeurosis

                                    d.  median cubital vein

            D.  Forearm      

                        1.  movement of wrist and hand

                                    a.  anterior compartment; flexors; median nerve for most

                                    b.  brachioradialis; outside compartment lateral side; flexor; radial nerve

                                    c.  posterior compartment; extensors; radial nerve   

 

VI   Lower Limb Muscles

            A.  Thigh

                        1.  move thigh

                                    a.  origins on pelvis

                                    b.  insertions on femur

                                                1.  iliopsoas - flexor

                                                2.  gluteus maximus

                                                3.  gluteus medius

                                                4.  gluteus minimus

                        2.  compartments

                                    a.  anterior compartment - extensors of leg (tibia)

                                    b.  medial compartment - adductors of femur    

                                     c.  posterior compartment - cross two joints; extensor of thigh, flex leg

          B.  Leg

                        1.   anterior compartment (extend toes, dorsiflex foot)

                        2.   lateral compartment (plantar flex, evert foot)

                        3.   posterior compartment (flexors)

 

 

At the end of this unit you should be able to:

    - identify some surface markings on the anterior body surface

    - discuss the structural arrangement of the abdominal muscles and their role in the body

    - define tendon, ligament, aponeurosis

    - identify on a diagram and discuss the "rotator cuff" muscles (origins, insertions, individual actions, group action),

    - identify on a diagram and discuss the muscles which moor the scapula

    - identify on a diagram and discuss the muscles which move the arm

    - identify on a diagram and discuss the muscles which move the forearm (at the elbow)

    - compare muscle of the anterior compartment of the arm and the posterior compartment of the arm

    - describe the structure of the cubital fossa and the structures within it

    - compare the function of muscles in the anterior and posterior compartments of the forearm

    - state the general origin and insertion of muscles of the thigh

    - label the three compartments of thigh muscles and state the general function of the muscles in each compartment

    - label the three compartments of the leg and state general function of muscles in each compartment

 

 

 

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