Innervation of muscles, roots of nerves and muscle action

obturator

external obturator

pectineus

gracilis

adductor

femoral

sartorious

iliopsoas

all heads of quadriceps

saphenous

sartorious

skin on medial side of the thigh, stifle, leg, tarsus, & remainder of paw

caudal cutaneous femoral

skin of dorsocaudal aspect of the pelvic limb

caudal gluteal

superficial gluteal

cranial gluteal

middle gluteal

piriformis

deep gluteal

tensor fasciae latae

sciatic

internal obturator

gemelli

quadratus femoris

biceps femoris

semitendinosus

semimembranosus

skin of caudal aspect of stifle

common fibular

cranial tibial

fibularis longus

long digital extensor

skin of dorsal aspect of paw

superficial fibular

paw?

lateral digital extensor

fibularis brevis

skin on dorsal aspect of paw

deep fibular

skin of dorsal aspect of paw

tibial

gastrocnemius

superficial digital flexor

popliteus

deep digital flexor

plantar muscles

skin on plantar aspect of paw

external obturator

obturator

pectineus

obturator

gracilis

obturator

adductor

obturator

sartorious

femoral (or saphenous)

iliopsoas

femoral

quadriceps femoris

femoral

skin on medial side of thigh, stifle, leg, tarsus, & remainder of paw

saphenous

skin of dorsocaudal aspect of the pelvic limb

caudal cutaneous femoral

superficial gluteal

caudal gluteal

middle gluteal

cranial gluteal

piriformis

cranial gluteal

deep gluteal

cranial gluteal

tensor fasciae latae

cranial gluteal

internal obturator

sciatic

gemelli

sciatic

quadratus femoris

sciatic

biceps femoris

sciatic

semitendinosus

sciatic

semimembranosus

sciatic

skin of the caudal aspect of the stifle

sciatic

cranial tibial

common fibular

fibularis longus

common fibular & superficial fibular

long digital extensor

common fibular

lateral deep digital flexor

superficial fibular & tibial

medial deep digital flexor

tibial

skin of dorsal aspect of paw

common fibular & superficial fibular & deep fibular

gastrocnemius

tibial

superficial digital flexor

tibial

popliteus

tibial

plantar muscles

tibial

skin on plantar aspect of paw

tibial

what is the tarsal tunnel

contains the tendon of the lateral digital flexor with its synovial sheath, the medial & lateral plantar nerves, & the caudal branch of the saphenous artery

name the 9 extrinsic muscles of the forelimb

1. trapezius

2. rhomboideus

3. brachiocephalicus

4. omotransversarius

5. latissimus dorsi

6. superficial pectoral

7. deep pectoral muscle

8. subclavis

9. serratus ventralis

action of rhomboideus

draw scapula dorsally

action of brachiocephalicus

• motion: extends shoulder joint and advances whole limb

• when both R and L contract, pull head ventrally

action of omotransversarius

• bends neck laterally

action of latissimus dorsi

• draws limb caudally when non-weight bearing

• draws trunk cranially when limb is fixed

action of superficial pectora

• prevent abduction of forelimbs when bearing weight

• adduct limb when not weight bearing

• support weight of body b/w limbs

action of deep pectoral muscle

• adducts and draws limb caudally when limb is free to swing

• advance trunk when limb is advanced and fixed

action of serratus ventralis

• cervical part draws scapula cranially when limb swings caudally

• thoracic part moves scapula caudally when limb advances cranially

Name the 12 intrinsic muscles of the proximal forelimb

1. supraspinatus

2. infraspinatus

3. deltoideus

4. teres major

5. teres minor

6. subscapularis

7. triceps brachii

8. anconeus

9. tensor fasciae antebrachii

10. coracobrachialis

11. biceps brachii

12. brachialis

Name extensor muscles of the distal forelimb

1. extensor carpi radialis

2. common digital extensor

3. lateral digital extensor

4. ulnaris lateralis

5. extensor carpi obliquus

6. interosseus muscle (suspensory ligament) axial and abaxial extensor branches

name the flexors of the distal forelimb

• flexor carpi ulnaris

• flexor carpi radialis

• superficial digital flexor

• deep digital flexor

Action of supraspinatus

• stabilises and extends shoulder joint

Action of infraspinatus

• stabilises shoulder joint

Action of deltoideus

• flexes shoulder joint

Action of teres minor

flexes shoulder joint

Action of teres major

flexes shoulder joint

Action of subscapularis

stabilises shoulder, adduction of antebrachium

Action of triceps brachii

• extend elbow

• long head flexes shoulder joint

Action of anconeus

extends elbow joint

Action of tensor fasciae antebrachii

• extends elbow

Action of coracobrachialis

flexes, adducts and stabilises shoulder joint

Action of biceps brachii

flexes elbow and extends shoulder joint

Action of brachialis

flexes elbow joint

state the muscles in the forelimb involved in:

1. adduction

2. pronation

3. suppination

4. shoulder flexors

5. shoulder extensors

6. elbow flexors

7. elbow extensors

8. carpus and digit flexors

9. carpus and digit extensors

1. subscapularis

2. pronator teres and pronator quadratus

3. short supinator, brachioradialis

4. deltoideus, teres major and teres minor

5. infraspinatus, supraspinatus

6. biceps brachii, brachialis

7. triceps brachii, tensor fasciae, anconeus, antebrachii

8. superficial digital flexor, deep digital flexor, flexor carpi radialis, flexor carpi ulnaris

9. extensor carpi radialis, extensor carpi obliquus, common digital extensor, lateral digital extensor, ulnaris lateralis

Compare and contrast anatomy and function of forelimb in: cats, rabbits, horses, ruminants, pigs and poultry

CATS
-have a clavicle
-more development of pronator/suppinator muscles (increased pronation and supination movement)

RABBITS
-large epicondyles
-well developed deltoideus muscles (allows fast and powerful movement, and burrowing)

HORSES
-vertical scapula, elongated metacarpals and phalanges (increase limb length and therefore stride length)
-fused radius and ulna (increased limb strength)

RUMINANTS
-cloven hooves (better grip for terrain)
-3rd and 4th metacarpal bones are fused, so only have 3 digits (can only flex and extend)

PIGS
-longer olecranon process (more efficient extension)
-irregular shape of radius head, locks into ulnar notch (provides stability, prevents supination)

POULTRY
-very light skeleton (allows slight flight)
-radius and ulnar bowed apart
-carpal and metacarpal bones fused, feathers attached to bones
-anular digit (thumb) can be raised (makes air flow over the wings)
-semi-lunate carpals (carpus moves sideways, so wings fold in sideways)

nerve root of suprascapular nerve

C6

nerve root of radial nerve

C7-T2

nerve root of ulnar nerve

C8-T2

nerve root of median nerve

C8-T1

nerve root of phrenic nerve

C5-7

nerve root of musculocutaneous nerve

C7 ± T1 + T2

nerve root of brachiocephalic nerve

C6, sometimes C5 and C7

nerve root of axillary nerve

C7/8

nerve root of ilio-psoas nerve

L4

nerve root of femoral nerve

L4 and L5

nerve root of obturator nerve

L4-6

nerve root of sciatic nerve

L5-S2