Skeletal muscle anatomy 2

glenoid labrum

cartilage labrum adds more socket to the glenoid fossa, helps cushion more, various activities can tear labrum (ex baseball pitching, power lifting), most common tear is SLAP tear (superior labrum from anterior to posterior, where biceps muscle attaches to supraglenoid tubercle)

major muscles of back

superficial layer - trapezius, latissimus dorsi

middle layer - splenius, rhomboids, supraspinatus, infraspinatus, teres minor

flexors of elbow

biceps brachii - crosses shoulder and elbow joint, flexes shoulder/elbow/supinates hand

brachialis - humerus to ulna, flexor of elbow

brachioradialis - humerus to radius (outermost muscle, you can feel it), flexor of elbow

extensors of elbow

triceps brachii - 3 heads (long crosses both joints, medias and lateral only for elbow), extends elbow and shoulder joints

anconeus - synergist with triceps, extends elbow

fascial adhesions

can form between adjacent fascia, restrict movement of muscles - makes muscles stiff

muscles of forearm/wrist (anterior)

protonator teres - medial epicondyle to radius, protonates (palm to floor)

flexor carpi radialis - medial epicondyle to distal radius, abduct wrist, flex wrist

flexor carpi ulnaris - medial epicondyle to distal ulna, adduct wrist, flex wrist

flexor digitorum muscles (superficialis, profundus) - flexion of digits 2-5, look where tendons go not the muscle belly

flexor pollicis longus - flex thumb

muscles of forearm/wrist (posterior)

supinator - lateral epicondyle of humerus to radius, supinates hand and forearm

extensor carpi radialis - abduct wrist

extensor carpi ulnaris - adduct wrist

extensor digitorum - extends digits 2-5

extensor pollicis - extends thumb

retinaculum

flexor on anterior side, extensor on posterior side, crosses wrist region from bone to bone, tough CT that prevents “bowstring” of tendons (ex carpal tunnel syndrome)

palmar aponeurosis

attaches palmaris longus to proximal phalanx of each finger, reinforces region

intrinsic muscles of hand

fine movement of fingers

thenar muscles - move the thumb

hypothenar muscles - move the little finger

midpalmar muscles - move all fingers between

lumbricals - flex metacarpal joints, extend ip joints (digits) (hand shape like L)

lateral/anterior hip muscles

psoas major - joins iliacus to lesser trochanter of femur, flex/rotate hip laterally (pulled groin muscle from moving too fast)

tensor fasciae latae - flex and abduct thigh

sartorius - crosses from lateral hip to medial knee, flex hip joint/flex knee joint/lateral rotation

quadriceps femoris (4 heads, all from femur to extend knee) - rectus femoris crosses hip (flex hip, extend knee), vastus medialis/lateralis/intermedius only move knee

adductor muscles of thigh

extend from pelvis to linea aspera on posterior surface of femur

pectineus - also flex/medially rotate thigh

adductor longus, adductor magnus, adductor brevis - also medial rotation of thigh

gracialis - also flexes knee

butt muscles and posterior thigh

gluteus muscles - maximus (extends, laterally rotates thigh), medius and minimus (abduct and medially rotate thigh)

hamstring muscles (extend hip flex knee) - semimembranous (like hot dog bun), semitendinosus (like hot dog), biceps femoris

innervation of compartments of thigh

anterior compartment = femoral nerve (vastus lateralis/intermedius/medialis, rectus femoris, sartorius)

medial compartment = obturator nerve (adductor magnus/brevis/longus, gracialis)

posterior compartment = sciatic nerve (biceps femoris, semitendinosus, semimembranous)

muscles of lower leg anterior component

all extend ankles/toes, tendons pass under retinaculum, dorsiflex foot (toes towards ceiling)

tibialis anterior - invert foot (roll ankle)

extensor hallucis longus - invert foot, extend big toe

extensor digitorum longus - foot eversion (roll other way), extend toes

muscles of lower leg lateral compartment

peroneus or fibularis muscles - plantar flex (dig toes into ground), evert foot (peroneus or fibularis longus/brevis)

muscles of lower leg posterior compartment

superficial - gastrocnemius (“calf”, arise from femur, flexes knee and ankle), plantaris and soleus (flex ankle)

deep - cross ankle joint to insert into foot, flex ankle joint (plantar flex) and toes, invert foot - tibialis posterior, flexor digitorum longus, flexor hallucis longus

muscles of plantar foot

sole of foot muscles, intrinsic muscles (arise and insert in foot), 4 layers get shorter as you go deeper, flex/adduct/abduct toes, plantar aponeurosis, platar fasciitis (chronic irritaion of plantar aponeurosis at calcaneal)