Kin 151 Exam 1 Study Guide

a single contractile unit, fundamental unit on striated muscle structure

• -longitudinal/parallel 
• -fusiform/spindle
• -fan/radiate
• -pennate
• -quadrate

• -their fiber pattern is parallel to the longitudinal axis of their muscle 
• -dominance is in creating endurance and large range of motion (long, flat, parallel) 
• -ex. sartorius, gracilis, rectus abdominis, etc

• - strong, single point power. it goes from a narrow attachment to a broad attachment 
• -varies between force and range of motion 
• -lateral/medial deltoid, pectoralis major, SITS, latissimus dorsi, etc

• - rounded belly with longer, tapered end fibers
• -vary between force and range of motion 
• - biceps brachii, brachialis, brachioradialis

• - short, parallel, featherlike fibers that lay at a diagonal or perpendicular to the longitudinal axis 
• -different types: uni, bi, multi, and quad 
• - many short fibers=force oriented 
• - examples
• -uni: extensor digitorum longus
• -bi: rectus femoris 
• multi: whole deltoid (technically anything that is also bi)

• -4 sided, short, parallel muscle fibers 
• -force oriented 
• -ex. pronator quadratus, rhomboids, supinator, gluteus maximus

• Nerve and all the muscle fiber cells it innervates. (Floyd, 55)
• A motor unit consists of a single motor neuron. (HWL, 71)

its the measure of how many motor units are activated in the muscle

• major gradation
• 1)type 1: the number of motor units that are being recruited 
• 2)type 2: The frequency of stimulation. If the stimulus is released at lower frequencies the muscle fibers have enough time to relax a little before the next impulse. But if the stimuli are released at high frequencies then the muscle fibers don’t have enough time to relax and eventually reach summation or maximal contraction.

• concentric- sarcomere shortens 
• eccentric- sarcomere lengthens 
• isometric- sarcomere stays at a length but there is tension 
• isotonic- constant rate of tension during full range of motion (concentric and eccentric), but the length and amount of energy needed change
• isokinetic-the muscle will shorten and lengthen, and tension will change, but the energy will remain the same

• to create force for...
• 1) movement- agonist 
• 2) resistance- antagonist 
• 3) coordination and control- antagonist and/or synergist 
• 4) stability- stabilizer and/or neutralizer
• 5) no force- relaxed

• concentric contraction creating a specific movement
• -main movers
• -assisters
• -they guide, refine, and minimize undesired movement

• eccentric contraction elongating at a specific rate 
• -coordinate the main movement
• -oppose the agonist
• -typically on opposite sides of the joint (not always)

• contraction of a muscle to allow another action of...
• - a different muscle
• - another part of a muscle 
• - co contract concentrically to create a new motion (mutual stabilizers)

isometric contraction to steady or support a bone or joint against the pull of other muscles

• epimysium-outside, surrounds the muscle 
• perimysium-middle/around, surrounds the bundle of muscle fibers 
• endomysium-inside, inside of the muscle wrapped around the individual muscle cells

membrane that encloses the muscle cell.. just beneath the endomysium

wrapped by perimysium. it holds a whole bundle of muscle fibers and their wrappings(endomysium and sarcolemma together)

a full lining/bundle of sarcomeres

• 1) sternal end of clavicle- sternoclavicular
• 2) acromial end of scapula- acromioclavicular

superior

conoid tubercle (inferior ridge)

inferior

trapezoid line

inferior

costal tuberosity

inferior

subclavian groove

inferior

spine of scapula

lateral (axillary) border

medial (vertebral) border

inferior angle

superior border

superior angle

corocoid process

supraglenoid tubercle

subscapular fossa

infraglenoid tubercle

supraspinous fossa

suprascapular notch

infraspinous fossa

acromion process

facet for the clavicle

water, calcium, collagen, cartilage

• -60-70% of bone is calcium 
• -calcium phosphate and carbonate form crystals, creating a long flat plate. 
• -purpose is to give strength because its so well compressed, so it resists crushing

• -Long parallel fibers, it overlaps like brick 
• - gives the bone a high tensile property and elasticity

• -they only pull, not push 
• -both ends move towards the center
• -tension moves towards the center for shortening or lenthening
• -they create tension, they dont flex
• -tends to act on all joints that it crosses

• -extensibility 
• -elasticity 
• -irritability/excitability 
• -contractility

the muscles ability to snap back

the muscles ability to be stretched

excitability is driven by the NS, its irritability is the ability to respond back to the nervous system

the ability to shorten, creates tension-can only pull!

• synarthrosis-not moveable ex. skull suture 
• amphiarthrosis-slightly moveable ex. pubic symphasis, acromioclavicular joint, rib-vertebral joint
• diarthrosis- freely moveable ex. shoulder, hip, knee, etc

• Gliding
• pivot 
• hinge 
• ellipsoid (condyloid)
• saddle 
• ball and socket

• -2 somewhat flat surfaces that glide past each other
• -they increase the amount of movement 
• -ex. carpals, tarsals, articular surfaces of vertebrae

• -one plane, uniaxial
• -movement is to open/close a joint with flexion and extension 
• -interphalangeal joints, tibia, fibula, talus

• -movement of a pivot point of one bone within a "ring-like structure" of another bone 
• -causes a true rotational movement 
• -one plane/uniaxial 
• -ex. atlas and axis (C1&C2), radial head and capitulum

• -a bone or set of bones that fit in an ellipsoid cavity and may rock in a couple of different directions
• -*Circumduction: flexion, extension, abduction, adduction 
• -2 planes, biaxial 
• -ex. radioulnar-carpal, metacarpalphalangeal

radial is abduction

ulnar is adduction

• -the bones or set of bones fit together like a rider in a saddle 
• -2 planes, biaxial 
• -ex. thumb (1st carpometacarpal)
• -taluscalcaneous

• -3 places, triaxial
• -hip and shoulder

• -3 joints 
• -2 joints
• -1 joint

• -incoming sensory information to spinal cord and brain 
• -ex. pressure, tension, pain, space, speed, etc
• *(influence, affect)
• -dorsal (back door)

• -outgoing reaction to the muscles and other tissues 
• -they tell the muscle to contract or relax
• *produces the effect of action
• -ventral (front door)

• -with two joint muscles 
• -active:When a muscle cannot shorten anymore, occurs with the agonist.
• -passive: When a muscle cannot stretch anymore, occurs with the antagonist.

Bi-articulate muscles are affected by their inability to allow the complete movements of the two joints they cross at the same time because they aren’t long enough. So they trade off tension to each other. There are 2 types of bi-articulate movement. Concurrent movement is when each muscle is contracted at one joint and relaxed at the other joint. Countercurrent movement happens when the bi-articulate muscles are either contracted or extended over both joints they cross. (HWL, 58-60)

rhomboid major

coracobrachialis

subclavius

supraspinatus

infraspinatus

subscapularis

pectoralis minor

rhomboid minor

• levator scapulae
• *dominant in scapular movement 
• *true elevator 
• o:c1-4 transverse processes
• i: superior angle, upper medial border of scapula

• pectoralis major
• *functionally 3 muscles
• 1)clavicular
• 2)sternal
• 3)costal 
• *twists at insertion 
• *most powerful in saggital plane

deltoid

latissimus dorsi

• trapezius
• *mutual neutralizer 
• *4 parts create the u
• I: creates a "small U" on posterior lateral clavicle, acromion process, spine of scapula
• O: 1. base of skull 2, 3, and 4: Spinous processes C7-T12  
• A: stabilize the scapula, adduction
• 1) elevation
• 2) elevation, outward/upward rotation, adduction 
• 3)adduction 
• 4) outward/upward rotation, depression, and adduction

• teres major-wrapped separately but functions as one with teres minor 
• minor
• o: C7-T1 at lamina 
• i: medial border at spine
• major
• o: T2-5 at lamina 
• i: middle medial border (not on inferior angle)
• A: True adductors

• teres minor-wrapped separately but functions as one with teres minor 
• minor
• o: C7-T1 at lamina 
• i: medial border at spine
• major
• o: T2-5 at lamina 
• i: middle medial border (not on inferior angle)
• A: True adductors

• serratus anterior
• -reaching, pulling, punching
• -abduction, outward/upward rotation, protraction of scapula
• -o: lateral surface of ribs 1-8 
• -i: anterior medial border of scapula