OIAs Lesson 1 Biomechanics

Origin of masseter

zygomatic arch

insertion of masseter

mandibular angle and ramus

action of masseter

elevates mandible

origin of deltoid

lateral 1/3 or clavicle

spine of scapula

acromion process of scapul

insertion of deltoid

deltoid tuberosity of humerus

action of deltoid

abducts arm

flexes arm at shoulder

rotates arm medially

extends arm at shoulder

rotates arm laterally

origin of biceps brachii

supraglenoid tubercle of the scapula

coracoid process of the scapula

insertion of biceps brachii

radial tuberosity of the radius

action of biceps brachii

flexes forearm at elbow

supinates forearm

origin of triceps brachii

infraglenoid tubercle of the scapula

posterior humerus

insertion of triceps brachii

olecranon process of the ulna

action of triceps brachii

extends forearm at elbow

origin of rectus femoris

anterior inferior iliac spine

insertion of rectus femoris

patella and tibial tuberosity

action of rectus femoris

extends leg at knee

flexes thigh at hip

origin of vastus lateralis

greater trochanter of the femur

intertrochanteric line

linea apera of femur

insertion of vastus lateralis

patella and tibial tuberosity

action of vastus lateralis

extends leg at knee

stabilizes knee

origin of vastus intermedius

shaft of the femur

insertion of vastus intermedius

patella and tibial tuberosity

action of vastus intermedius

extends leg at knee

origin of vastus medialis

linea aspera of femur

intertrochanteric line

insertion of vastus medialis

patella and tibial tuberosity

action of vastus medialis

extends leg at knee

stabilizes patella

origin of gluteus maximus

posterior ilium

sacrum

coccyx

insertion of gluteus maximus

iliotibial tract

gluteal tuberosity of femur

action of gluteus maximus

extends thigh at hip

rotates thigh laterally

abducts thigh

origin of gluteus medius

lateral surface of ilium

insertion of gluteus medius

greater trochanter of femur

action of gluteus medius

abducts thigh

rotates thigh medially

origin of biceps femoris

ischial tuberosity

linea aspera

insertion of biceps femoris

head of fibula

lateraly condyle of tibia

action of biceps femoris

extends thigh at hip

flexes leg at knee

rotates leg laterally

origin of semimembranosus

ischial tuberosity

insertion of semimembranosus

medial condyle of tibia

action of semimembranosus

extends thigh at hip

flexes leg at knee

rotates leg medially

origin of semitendinosis

ischial tuberosity

insertion of semitendinosus

medial tibia

action of semitendinosis

extends thigh at hip

flexes leg at knee

rotates leg medially

origin of gastrocnemius

lateral condyle of femur

medial condyle of femur

insertion of gastrocnemius

calcaneus

action of gastrocnemius

plantar flexes foot at ankle

origin of soleus

proximal tibia

proximal fibula

interosseous membrane

insertion of soleus

calcaneous

action of soleus

plantar flexes foot at ankle

origin of tibialis anterior

lateral condyle of tibia

insertion of tibialis anterior

medial cuneiform

1st metatarsal

action of tibialis anterior

dorsiflexes foot at ankle

inverts foot