Functional Anatomy

Origin

where it comes from

Insertion

where it inserts itself into

Flexion

smaller joint angle

Extension

larger joint angle

Eccentric

force is going onto you (example:going down during bench press)

Isocentric

holding position (example:plank)

Concentric

going against the force (example:going up during squats)

Bi-articulate Muscles

crosses 2 joints; flexion of one and extension of another (example:hamstring muscle-flexes knee and extends hip)

Unilateral

1 leg or 1 arm (unicycle)

Bilateral

2 legs or 2 arms (bicycle)

Open Chain Movement

hands and feet are able to move freely (example:bicep curl and bench press)

Closed Chain Movement

hands and feet are not able to move (example:push-up and squats)

Sagittal

splits you in half vertically

Frontal

splits you from back to front

Transverse

splits you in half horizontally

Biceps

Origin:supraglenoid tubercle of scapula, coracoid process of scapula, humerus (shoulder)

Insertion:radial or ulna tuberosity (elbow/forearm)

Function:flexion at the elbow (primary); supination at the elbow,flexion at the shoulder (secondary); biceps brachii long head (bi-articulate)

Triceps

Origin:infraglenoid tubercle of scapula,humerus (shoulder)

Insertion:olecranon of the ulna (elbow)

Function:extension of the forearm at the elbow (primary)

Anterior Deltoid

Origin:lateral third of clavicle

Insertion:deltoid tuberosity of the humerus

Function:flexion at the shoulder (deltoid is shoulder abduction)-primary; abduction and internal rotation at the shoulder (secondary)

Pectoralis Major

Origin:sternum and clavicle

Insertion:humerus

Function:horizontal adduction at the shoulder (primary); internal rotation and flexion at the shoulder (secondary)

Abdominals

Origin:pubis bone, inguinal line, anterior iliac crest (pelvis)

Insertion:xiphoid process of sternum, ribs

Function:trunk flexion (rectus abdominis), trunk rotation (internal and external oblique), and stabilizing torso and pelvis, valsalva maneuver (transverse abdominis)

Rhomboid

Origin:spinous process of T2-T5 vertebra

Insertion:medial boarder of the scapula

Function:scapular retraction (primary); elevate and rotate the scapula (secondary)

Posterior Deltoid

Origin:spine of the scapula

Insertion:deltoid tuberosity of the humerus

Function:shoulder extension w/ latissimus dorsi (primary); external rotation and horizontal abduction at the shoulder (secondary)

Latissimus Dorsi

Origin:illium, spinous processes, ribs, inferior angle of scapula

Insertion:humerus

Function:shoulder adduction (primary); shoulder extension (secondary)

Erector Spinae

Origin:pelvic, vertebral and rib bones in lower to mid back

Insertion:vertebral and rib bones located higher up in back and neck

Function:trunk extension-bilateral (primary); lateral flexion of spine-unilateral, posture (secondary)

Calves (gastronemius,soleus)

Origin:lateral and medial femoral condyle, tibia and fibula

Insertion:calcaneus

Function:ankle plantar flexion (primary); stabilization of the knee/flexion of the knee (secondary); gastrocnemius-knee flexion and ankle plantar flexion (bi-articulate)

Quadriceps

Origin:femur, anterior inferior iliac spine/ilium of pelvis

Insertion:tibial tuberosity via patella/quad tendon

Function:extension of the knee (primary); flexion of the hip-psoas is the primary hip flexor (secondary); rectus femoris-knee extension and hip flexion (bi-articulate)

Hamstrings

Origin:ischial tuberosity of the pelvis

Insertion:medial condyle of tibia, lateral head of fibula

Function:knee flexion (primary); hip extension, tibial stabilization/rotation (secondary); biceps femoris long head, semitendinosus, semimembranosus (bi-articulate)

Gluteus Maximus

Origin:gluetal surface of the illim and posterior inferior surface of sacrum and coccyx

Insertion:greater trochanter of femur, gluteal tuberosity of femur and iliotibial tract (IT Band)

Function:hip extension

Hip Abductors

Origin:gluteal surface of the ilium

Insertion:anterior and lateral surface of the greater trochanter

Function:hip abduction (primary); hip internal rotation (anterior fibers), hip external rotation (posterior fibers), stabilization of pelvis (secondary)

Hip Adductors

Origin:pubis and ischium

Insertion:mainly medial and posterior surface of femur

Function:hip adduction (primary), stabilization of pelvis; hip extension (adductor magnus); gracilis-crosses hip and knee (bi-articulate)