ACTIVITIES 5 & 6: APPENDICULAR AND AXIAL MUSCLES Laboratory Objectives: 1. Histology: review histology of skeletal muscle tissue. 2. Identify muscles listed on models and/or cadavers. 3. When indicated, identify the action and attachments for each muscle. Skeletal muscle identification: • You will be required to identify each of the following muscles or associated structures on the cadavers and/or models in lab. • If the table is shaded in a particular box, it means you are not responsible for that information. • Muscle actions are required for each muscle. • Remember: Spelling is important! Practice writing and rewriting the names of each muscle and associated structure. • You are NOT responsible for the nerve innervating each muscle until you do the nervous system activities in laboratory. Note: CN = cranial nerve APPENDICULAR MUSCLES: These muscles control the movement of the upper and lower limbs, pelvic and pectoral girdles. TABLE 1. MUSCLES THAT MOVE THE PECTORAL GIRDLE NAME
ACTION
NERVE (FROM BRACHIAL PLEXUS, EXCEPT TRAPEZIUS)
Muscles that are attached only to the axial skeleton and thus move the pectoral girdle 1. trapezius
-superior fibers: elevate scapula, elevate clavicle -inferior fibers: depress scapula
2. levator scapulae
elevates scapula
3. serratus anterior
protracts and stabilizes scapula
long thoracic nerve
4. pectoralis minor
protracts and depresses scapula
medial pectoral nerve
5. rhomboid major
-elevates and retracts scapula -rotates scapula inferiorly -elevates and retracts scapula -rotates scapula inferiorly
6. rhomboid minor
1
accessory nerve (CN XI)
TABLE 2. MUSCLES THAT ATTACH TO THE AXIAL SKELETON AND TO THE HUMERUS. These muscles move the glenohumeral or shoulder joint. NAME
PROXIMAL ATTACHMENT (ORIGIN)
DISTAL ATTACHMENT (INSERTION)
ACTION
NERVE (BRACHIAL PLEXUS)
ROTATOR CUFF MUSCLES (4 MUSCLES) 1. supraspinatus 2. infraspinatus 3. subscapularis 4. teres minor
supraspinous fossa of scapula infraspinous fossa of scapula subscapular fossa of scapula lateral border of scapula
5. teres major
lateral border and angle of scapula
6. latissimus dorsi
-spinous processes of lower thoracic vertebrae -lower ribs -iliac crest -acromial end of clavicle -acromion and spine of scapula
7. deltoid
8. pectoralis major
-clavicle -costal cartilages -body of sternum
TABLE 3. ANTERIOR COMPARTMENT OF THE ARM NAME PROXIMAL ATTACHMENT (ORIGIN)
greater tubercle of humerus greater tubercle of humerus lesser tubercle of humerus greater tubercle of humerus lesser tubercle and intertubercular groove of humerus intertubercular groove of humerus deltoid tuberosity of humerus greater tubercle and intertubercular groove of humerus DISTAL ATTACHMENT (INSERTION)
collectively, stabilize and rotate shoulder (glenohumeral) joint
extends, adducts, and medially rotates arm at shoulder extends, adducts, and medially rotates arm at shoulder (swimming, climbing rope, hammering) abducts, flexes, extends, and rotates arm at shoulder
axillary nerve
flexes, adducts, and medially rotates arm at shoulder
lateral pectoral nerve and medial pectoral nerve
ACTION
NERVE (BRACHIAL PLEXUS)
1. biceps brachii long head
supraglenoid tubercle of scapula
short head
coracoid process of scapula
radial tuberosity
-flexes and supinates forearm at elbow -flexes arm at shoulder (weak)
musculocutaneous nerve
2. coracobrachialis
coracoid process of scapula
middle medial shaft of humerus
adducts and flexes arm at shoulder
musculocutaneous nerve
3. brachialis
distal, anterior surface of humerus
coronoid process of ulna
flexes forearm at elbow
musculocutaneous nerve
4. brachioradialis
lateral distal humerus
styloid process of radius
flexes forearm at elbow
2
radial nerve
TABLE 4. POSTERIOR COMPARTMENT OF THE ARM NAME PROXIMAL
DISTAL
ATTACHMENT (ORIGIN)
ACTION
NERVE (BRACHIAL PLEXUS)
ATTACHMENT (INSERTION)
1. triceps brachii (long, lateral, and medial heads) long head lateral head medial head
infraglenoid tubercle of scapula posterior shaft of humerus posterior shaft of humerus distal to radial groove
TABLE 5. ANTERIOR COMPARTMENT OF THE FOREARM NAME
olecranon process of ulna
-extends forearm at elbow -assists in arm adduction at shoulder
ACTION
NERVE (BRACHIAL PLEXUS)
1. pronator teres
pronates forearm
median nerve
2. flexor carpi radialis
-flexes wrist -abducts hand at wrist -flexes wrist (weak) -tenses fascia of palm -flexes wrist -adducts hand at wrist -flexes wrist -flexes joints of digits 2-5 (MP and PIP joints) -flexes wrist -flexes joints of digits 2-5 (MP, PIP, DIP joints)
median nerve
3. palmaris longus 4. flexor carpi ulnaris 5. flexor digitorum superficialis 6. flexor digitorum profundus
radial nerve
median nerve ulnar nerve median nerve
flexor retinaculum (associated structure) MP = metacarpophalangeal; IP= interphalangeal; PIP = proximal interphalangeal; DIP = distal interphalangeal
3
TABLE 6. POSTERIOR COMPARTMENT OF THE FOREARM NAME
ACTION
NERVE (BRACHIAL PLEXUS)
1. extensor carpi radialis longus
-extends wrist -abducts hand at wrist
radial nerve
2. extensor carpi radialis brevis
-extends wrist -abducts hand at wrist
radial nerve
3. extensor carpi ulnaris
-extends wrist -adducts hand at wrist
radial nerve
4. extensor digitorum
-extends wrist -extends joints of digits 2-5 (MP, PIP, DIP joints)
radial nerve
5. abductor pollicis longus
-abducts thumb -extends wrist (weak)
radial nerve
6. extensor pollicis longus
-extends thumb joints (MP and IP joints) -extends wrist (weak)
radial nerve
7. extensor pollicis brevis
- extends thumb joints (MP and IP joints) - extends wrist (weak)
radial nerve
8. supinator
supinates forearm
radial nerve
extensor retinaculum (associated structure) TABLE 7. ANTERIOR COMPARTMENT OF THE THIGH NAME PROXIMAL ATTACHMENT (ORIGIN)
1. sartorius
anterior superior iliac spine
DISTAL ATTACHMENT (INSERTION)
ACTION
tibial tuberosity, medial side
-flexes and laterally rotates thigh at hip -flexes leg and medially rotates leg at knee (sitting crosslegged on floor)
NERVE (LUMBAR PLEXUS) femoral nerve
QUADRICEPS FEMORIS GROUP: FOUR MUSCLES WITH A COMMON INSERTION POINT
2. rectus femoris
-extends leg at knee -flexes thigh at hip
femoral nerve
extends leg at knee
femoral nerve
4. vastus medialis
extends leg at knee
femoral nerve
5. vastus intermedius
extends leg at knee
femoral nerve
3. vastus lateralis
anterior inferior iliac spine
patella via quadriceps tendon and then tibial tuberosity via patellar ligament
4
TABLE 8. ILIOPSOAS GROUP NAME
PROXIMAL
DISTAL
ACTION
ATTACHMENT (ORIGIN)
ATTACHMENT (INSERTION)
NERVE (LUMBAR PLEXUS)
1. iliacus *
iliac fossa
lesser trochanter of femur
flexes thigh at hip
femoral nerve
2. psoas major* *These two muscles are collectively known as the iliopsoas
T12-L5 vertebrae
lesser trochanter of femur
flexes thigh at hip
branches of lumbar plexus
TABLE 9. MEDIAL COMPARTMENT OF THE THIGH NAME PROXIMAL
DISTAL
ATTACHMENT (ORIGIN)
ACTION
ATTACHMENT (INSERTION)
1. pectineus 2. adductor longus 3. adductor magnus
4. adductor brevis 5. gracilis
inferior ramus and body of pubis
TABLE 10. POSTERIOR COMPARTMENT OF THE THIGH NAME PROXIMAL ATTACHMENT (ORIGIN)
NERVE (LUMBAR PLEXUS)
proximal medial surface of tibia
DISTAL ATTACHMENT (INSERTION)
-adducts thigh at hip -flexes thigh at hip (weak) -adducts thigh at hip -flexes thigh at hip (weak) -adducts thigh at hip -flexes,extends and laterally rotates thigh at hip adducts thigh at hip
femoral nerve or obturator nerve
-adducts thigh at hip -flexes leg at knee
obturator nerve
ACTION
NERVE (SACRAL PLEXUS)
obturator nerve obturator nerve sciatic nerve obturator nerve
HAMSTRINGS GROUP: (3 MUSCLES) 1. semitendinosus
ischial tuberosity
proximal medial surface of tibia
2. semimembranosus
ischial tuberosity
medial condyle of tibia
3. biceps femoris • long head • short head
long head: ischial tuberosity short head: linea aspera of femur
head of fibula
5
-extends thigh at hip -flexes leg at knee -medially rotates leg at knee -extends thigh at hip -flexes leg at knee -medially rotates leg at knee -extends thigh at hip -flexes and laterally rotates leg at knee
tibial division of sciatic nerve tibial division of sciatic nerve tibial division of sciatic nerve
TABLE 11. GLUTEAL MUSCLES NAME 1. tensor fascia latae
PROXIMAL
DISTAL
ATTACHMENT (ORIGIN)
ATTACHMENT (INSERTION)
iliotibial band
3. gluteus medius
-iliac crest -anterior superior iliac spine -iliac crest -sacrum -coccyx iliac crest
4. gluteus minimus
lateral surface of ilium
greater trochanter of femur
5. piriformis
anterior lateral surface of sacrum
greater trochanter of femur
2. gluteus maximus
-iliotibial band - gluteal tuberosity/ linea aspera of femur greater trochanter of femur
ACTION -abducts thigh at hip -medially rotates thigh at hip -extends thigh at hip -laterally rotates thigh at hip -abducts thigh at hip -medially rotates thigh at hip -abducts thigh at hip -medially rotates thigh at hip laterally rotates thigh at hip
NERVE (SACRAL PLEXUS) superior gluteal nerve inferior gluteal nerve superior gluteal nerve superior gluteal nerve
6. iliotibial band/tract (associated structure) TABLE 12. ANTERIOR COMPARTMENT OF THE LEG NAME PROXIMAL
DISTAL ATTACHMENT (INSERTION)
ATTACHMENT (ORIGIN)
1. tibialis anterior
lateral condyle and proximal shaft of tibia
-metatarsal I -medial cuneiform
2. extensor digitorum longus 3. extensor hallucis longus
TABLE 13. LATERAL COMPARTMENT OF THE LEG NAME 1. fibularis (peroneus) longus 2. fibularis (peroneus) brevis
ACTION
ACTION -dorsiflexes foot at ankle -inverts foot at ankle -extends toes 2-5 -dorsiflexes foot at ankle -extends hallux -dorsiflexes foot at ankle
NERVE (SACRAL PLEXUS) deep fibular nerve deep fibular nerve deep fibular nerve
NERVE (SACRAL PLEXUS)
-everts foot at ankle -plantar flexion at ankle (weak) -everts foot at ankle -plantar flexion at ankle (weak)
6
superficial fibular nerve superficial fibular nerve
TABLE 14. POSTERIOR COMPARTMENT OF THE LEG NAME PROXIMAL
DISTAL
ATTACHMENT (ORIGIN)
ACTION
ATTACHMENT (INSERTION)
1. gastrocnemius
lateral and medial condyles of femur
calcaneus via calcaneal tendon
2. soleus
-head and proximal shaft of fibula -medial border of tibia
calcaneus via calcaneal tendon
3. tibialis posterior 4. flexor digitorum longus 5. flexor hallucis longus
7
NERVE (SACRAL PLEXUS)
-plantar flexes foot at ankle -flexes leg at knee plantar flexes foot at ankle
tibial nerve
-plantar flexes foot at ankle -inverts foot at ankle -plantar flexes foot at ankle -flexes toes 2-5 -plantar flexes foot at ankle -flexes joints of hallux
tibial nerve
tibial nerve
tibial nerve tibial nerve
AXIAL MUSCLES: These muscles have both their origins and insertions on the axial skeleton. TABLE 15. MUSCLES OF FACIAL EXPRESSION NAME
ACTION
NERVE
1. frontalis (frontal belly of occipitofrontalis)
moves scalp forward, raises eyebrows, wrinkles forehead
facial nerve (CNVII)
2. occipitalis (occipital belly of occipitofrontalis)
moves scalp backward
facial nerve (CNVII)
2. orbicularis oris
compresses and purses lips (kiss muscle)
facial nerve (CNVII)
3. orbicularis oculi
closes eye (blink muscle)
facial nerve (CNVII)
4. platysma
pulls lower lip inferiorly, tenses skin of neck
facial nerve (CNVII)
5. zygomaticus major and zygomaticus minor
elevates corners of mouth (smiling muscle)
facial nerve (CNVII)
6. buccinator
compresses cheeks, as in chewing, whistling, playing a wind instrument, and suckling in infants
facial nerve (CNVII)
TABLE 16. MUSCLES OF MASTICATION (CHEWING) NAME
ATTACHMENT (ORIGIN)
ATTACHMENT (INSERTION)
ACTION
NERVE
1. temporalis
parietal and frontal bones
coronoid process of mandible
elevates and retracts mandible
trigeminal nerve (CNV)
2. masseter
zygomatic arch
coronoid process and ramus of mandible
elevates and protracts mandible; jaw closure
trigeminal nerve (CNV)
8
TABLE 17. NECK MUSCLES NAME
ATTACHMENT (ORIGIN)
ACTION
ATTACHMENT (INSERTION)
1. sternocleidomastoid
-manubrium of sternum -sternal end of clavicle
mastoid process of temporal bone
2. splenius capitis and splenius cervicis
ligamentum nuchae (the connective tissue covering the spinal processes of the cervical vertebrae)
-occipital bone -mastoid process of temporal bone
TABLE 18. MUSCLES OF VERTEBRAL COLUMN NAME
NERVE
-one side: lateral flexion with rotation of head to opposite side -both sides: flexes head & neck -one side: turns head to same side -both sides: extends head & neck
ACTION
accessory nerve (CNXI)
cervical spinal nerves
NERVE
Erector spinae groups (3): 1. iliocostalis group (lateral)
-one side: laterally bends the vertebral column
2. longissimus group (intermediate)
-both sides: extends neck and vertebral column; maintains posture
3. spinalis group (medial)
cervical, thoracic, and lumbar spinal nerves cervical and thoracic spinal nerves cervical and thoracic spinal nerves
4. quadratus lumborum (not part of erector spinae groups)
-one side: laterally bends the vertebral column -both sides: extends vertebral column
TABLE 19. MUSCLES OF RESPIRATION NAME
ACTION
thoracic and lumbar spinal nerves
NERVE
1. external intercostals
elevates ribs during normal inspiration
intercostal nerves (from thoracic spinal nerves)
2. internal intercostals
depresses ribs during forced exhalation
intercostal nerves (from thoracic spinal nerves)
3. diaphragm
contraction depresses (flattens) diaphragm and expands the thoracic cavity during normal inspiration
phrenic nerves (from cervical plexus)
9
TABLE 20. MUSCLES OF THE ABDOMINAL WALL NAME 1. external oblique 2. internal obliques 3. rectus abdominis 4. transversus abdominis
ACTION
NERVE
-both sides: flexes vertebral column & compresses abdominal wall -one side: lateral flexion of vertebral column -both sides: flexes vertebral column & compresses abdominal wall -one side: lateral flexion of vertebral column flexes vertebral column & compresses abdominal wall
thoracic spinal nerves
-both sides: flexes vertebral column & compresses abdominal wall -one side: lateral flexion of vertebral column
thoracic spinal nerves
5. inguinal ligament (associated structure)
10
thoracic spinal nerves thoracic spinal nerves
