Characteristics used to Name Muscles

Directional terms

orientation of muscle fascicles relative to body’s midline

What are the characteristics used to name muscles?

Direction (fascicle arrangement), size, shape, action, number of origins (tendon), location, origin+insertion

D: Rectus

Ex)

parallel to midline

rectus femoris, rectus abdominis

D: Transverse

Ex)

Perpendicular to the midline

transversus abdominis

D: Oblique 

Ex) 

diagonal to midline 

external oblique and internal oblique 

Size

relative size of the muscle

S: Maximus

Ex)

largest

Gluteus maximus

S: Minimus

Ex) 

smallest 

gluteus minimus 

S: Longus

Ex)

long

extensor carpi radialis longus

S: Brevis

Ex) 

short

adductor brevis 

S: Latissimus

Ex)

widest

latissimus dorsi

S: Longissimus

longest

S: Magnus

Ex) 

large 

adductor magnus

S: Major

Ex)

larger

pectoralis major

S: Minor

Ex) 

smaller 

pectoralis minor 

S: Vastus

huge

vastus lateralis, medialis, and intermedius 

Shape

relative shape of muscle

SH: Deltoid

Ex

triangular 

deltoid 

SH: Trapezius

Ex)

trapezoid

trapezius

SH: Serratus

Ex)

saw-toothed

serratus anterior

SH: Rhomboid

Ex)

diamond shaped

Rhomboid minor and major

SH: Gracilis 

Ex) 

slender

gracilis 

Action

principal action of the muscle

A: Flexor

Ex)

decreases a joint angle

flexor carpi radialis

A: Extensor

Ex)

increases a joint angle

extensor carpi radialis

A: Abductor 

Ex)

moves a bone away from the midline 

abductor pollicis longus 

A: Adductor

Ex) 

moves a bone closer to the midline 

adductor longus, magnus, and brevis

A: Levator

Ex) 

raises or elevates a body part 

levator scapulae 

A: Tensor 

Ex)

makes a body part rigid 

tensor fasciae latae 

Number of origins:

number of tendons of origin

NO: Biceps

two origins

NO: Triceps

three origins

NO: Quadriceps

four origins