BIOMECHANICS

name the 5 joints that comprise the shoulder

• sternoclavicular

• acromioclavicular

• scapulothoracic

• glenohumeral

• coracoclavicular

what are the 9 motions of the shoulder?

• flexion

• extension

• adduction

• abduction

• lateral rotation

• medial rotation

• horizontal abduction

• horizontal adduction

• circumduction

what are the major flexors of the shoulder?

• anterior deltoid

• pectoralis major

• biceps brachii

what are the major extensors of the shoulder?

• middle deltoid

• latissimus dorsi

• teres major

what muscles abduct the shoulder?

• middle deltoid

• supraspinatus

muscles that adduct the shoulder

• pectoralis major

• latissimus dorsi

• teres major

muscles that perform the horizontal adduction at the shoulder

• pectoralis major

• anterior deltoid

muscles that perform horizontal abduction at the shoulder

• posterior deltoid 

• infraspinatus

• teres minor

bones of the elbow

• humerus

• ulna

• radius

joints of the elbow

• humeroulnar

• humeroradial

• radioulnar

primary flexors of the elbow

• biceps brachii

• brachialis

• brachioradialis

primary extensors of the elbow

• triceps brachii

• ancondeus

wrist flexors are located on which side?

anterior forearm

wrist extensors are located on which side

posterior forearm

intrinsic vs extrinsic hand muscles?

• intrinsic: attach only distal to the wrist

• extrinsic: attach proximal & distal to the wrist

common elbow injuries

• medial epicondylitis: little leaegue elbow & medial distal humerus

• lateral epicondylitis: tennis elbow & lateral idstal humerus

metacarpalphalangeal 2-5 motions?

• flexion

• extension

• adduction

• abduction

• circumduction

metacarpalphalangel joint 1 (THUMB) unique motion?

opposition

name the 3 primary ligaments of the hip

• iliofemoral

• pubofemoral

• ischiofemoral

pelvic anterior telt - femur motion?

extension

pelvic lateral tilt away - femur motion

flexion

pelvic lateral tilt toward - femur motion

abduction

pelvic lateral tilt away - femur motion

adduction

major hip flexors

• iliopsoas

• rectus femoris

major hip extensors

• gluteus maximus

• hamstrings

hip abductors

• gluteus medius

• gluteus minimus

• tensor fasciae latae

hip adductors

• adductor longus

• adductor brevis

• adductor magnus

• gracilis

3 major loads on the hip

• body weight

• muscle force from abductors

• joint reaction force

hamstring strain most often occurs with what hip & knee positions

hip is flexed and knee is extended

2 joints of the knee

• tibiofemoral

• patellofemoral

4 primary knee ligaments

• ACL

• PCL

• Medial collateral ligament (MCL)

• Lateral collateral igament (LCL)

muscles responsible for knee flexion

hamstrings (Biceps femoris, semimembranosus, semitendinosus)

muscles responsible for knee extension

quadriceps (vastus lateralis, vastus medialis, vastus intermedius, rectus femoris)

what muscle “unlocks” the knee

popliteus

“Screw home” mechanism tibial rotation direction

external rotation

PCL prevents what motion

posterior tibial motion

ACL prevents what motion

anterior tibial motion

q-angle associated pain disorder?

patellofemoral pain syndrome

ACL injury risk demographics

• females

• 14-18 years old

• court & field sports (Jumping, cutting)

primary ankle joints

• tibiotalar

• distal tibiofibular

muscles for dorsiflexion

• tibialis anterior

• extensor hallucis longus

• extensor digitorum longus

muscles for plantarflexion

• soleus

• gastrocnemius

majority of ankle sprians occur in what motion

inversion

describe the three primary classifications of joints and their subgroups

• fibrous joints (Sutures)

• cartilaginous joints (synchondroses)

• synovial joints (hinge joints)

explain the 4 essential components that every diarthrotic or synovial joint must have

every diarthrotic/synovial joint have have articular cartilage, joint capsule, synovial membrane, and synovial fluid

examples of the 6 primary types of diarthrotic joints

• hinge joint - elbow

• ball & socket joint - shoulder

• pivot joint - neck

• saddle joint - thumb

• condyloid joint - wrist

• gliding joint - between carpal bones

define primary functions of articular cartilage

• reduce friction between bones

• absorb shock

• provide a smooth surface for joint movement

how are articular cartilage and fibrocartilage similar and different

similar - both types of carilage that provide support and cushioning in joints

different - in composition and function. denser and provides support in areas like intervertebral discs

describe 2 types of muscle injuries or pathologies

• strains - involves the overstretching or tearing of muscle fibers

• tendinitis - inflammation of a tendon due to overuse or repetitive stress

differences between muscular power, strength, and endurance

• muscular power - ability to exert force quickly

• strength - maximum amount of force on a muscle can produce

• endurance - the ability to sustain repeated contractions over time without fatigue

define mechanical delay and how it can be measured

the time lag between the onset of muscle activation and the onset of force production

describe the force-velocity and length-tension relationships for muscle tissure

indicated that as the velocity of muscle contraction increases, the force produced decreases

describe 3 types of muscle contractions

• concentric (they shorten while generating force)

• eccentric (they lengthen while generating force)

• isometric (the length remains the same while generating force)

explain what pennation angle refers to for muscle fibers and why it is important

the angle between the muscle fibers and the line of action of the muslce

identify 3 difference between type 1, type lla, and type llb muscle fibers

• type 1 - slow twitch, fatigue resistant, & primarily use aerobic metabolism

• type lla - fast twitch, moderately fatigue resistant & can use both aerobic and anaerobic metabolism

• type llb - fast twitch, fatigue prone, & primarily rely on anaerobic metabolism 

describe the process of a muscle fiber going from a twitch to full tetanus

through increased frequency of stimulation

define the basic structural unit of a muscle fiber and what comprises it

sarcomere. it comprises myofilaments, specifically actin & myosin, along w/ other proteins that regulate contraction such as troponin and tropomyosin

describe the stretch-shortening cycle and provide an example

a muscle action that involves an eccentric contraction followed by a concentric contraction.

EXAMPLE: a jump. where a person bends their knees (eccentric) before jumping upward (concentric)

describe the differences between PEC and SEC

• PEC - parallel elastic component - elastic properties of muscle fibers and connective tissue that are parallel to the muscle fibers contributing to passive tension

• SEC - series elastic component - elastic properties of tendons other structures in series with the muscles fibers which store elastic energy during muscle contraction

what are the 4 behavioral properties of the musculotendinous unit

• extensibility

• elasticity

• irritability (excitability)

• contractility 

describe two different joint injuries or pathologies

• torn meniscus

• osteoarthritis

list the 5 types of stretches and their benefits & downsides

• static stretching - improves flexibility but can reduce strength temporarily

• dynamic stretching - prepares muscles for activities but you have to have proper technique

• ballistic stretching - increases range quickly but theres a risk of injury

• proprioceptice neuromuscular facilitation stretching - effective for increasing flexibility but requires someone

• active stretching - strengthens muscles but may be difficult for beginners

anterior deltoid motions

• shoulder flexion

• abduction

• medial rotation

middle deltoid motions

• shoulder abduction, horizontal abduction, assists with lateral rotation

posterior deltoid motions

• shoulder extension

• horizontal abduction

• lateral rotation

pectoralis major (clavicular head) motions

• shoulder flexion

• horizontal adduction

• medial rotation

pectoralis major (sternal head) motions

• shoulder extension

• adduction

• horizontal adduction

• medial rotation

supraspinatus motions

• shoulder abduction

• assists with lateral rotation

coracobrachialis motions

• shoulder flexion

• adduction

• horizontal adduction

latissimus dorsi motions

• shoulder extension

• adduction

• medial rotation

• horizontal abduction

teres major motions

• shoulder extension

• adduction

• medial rotation

infraspinatus motions

• lateral rotation

• horizontal abduction

teres minor motions

• lateral rotation

• horizontal abduction

subscapularis motions

• medial rotation

biceps brachii (long head) motions

• shoulder flexion

• assists with abduction

• lateral rotation

• horizontal abduction

biceps brachii (short head) motions

• shoulder flexion

• assists with adduction

• medial rotation

• horizontal adduction

biceps brachii motions (elbow version)

• elbow flexion

• assists with supination

• shoulder flexion

brachialis motions

• elbow flexion

brachioradialis motions

• elbow flexion

• assists with pronation & supination to neutral

pronator teres motions

• forearm pronation

• assists with elbow flexion

pronator quadratus motions

• forearm pronation

triceps brachii motions

• elbow extension

• long head assists with shoulder extension & adduction

anconeus motions

• assists with elbow extension

• stabilizes elbow during supination

rectus femoris motions

• hip flexion

• assists with knee extension

Iliopsoas motions

• hip flexion

• assists with lateral rotation

pectineus motions

• hip flexion

• adduction

• assists with medial rotation

gluteus maximus motions

• hip extension

• lateral rotation

gluteus medius motions

• hip abduction

• medial rotation

gluteus minimus motions

• hip abduction

• medial rotation

gracilis motions

• hip adduction

• assists with flexion

adductor longus motions

• hip adduction

• assists with flexion

adductor brevis motions

• hip adduction

• lateral rotation

adductor magnus motions

• hip adduction

• extension

• lateral rotation (posterior fibers)

semitendinosus motions

• hip extension

• medial rotation of leg

rectus femoris motions

• knee extension

• assists with hip flexion

vastus lateralis motions

• knee extension

vastus medialis motions

• knee extension

vastus intermedius motions

• knee extension

sartorius motions

• knee flexion

• medial rotation

semimembranosus motions

• knee flexion

• medial rotation