Muscles Flashcards
Superficial pectoral
Origin: sternum
Insertion: crest of greater tubercle and cranial humeral border
Action: adduct thoracic limb
Deep pectoral
Origin: sternum
Insertion: greater/lesser tubercles
Action: adduct thoracic limb and pull it caudally
Brachiocephalicus
Origin: clavicular intersection
Insertion: distal cranial humerus, mastoid process of temporal bone, dorsal midline of neck
Action: pull thoracic limb cranially and depress head/neck laterally
Omotransversarius
Cranial-most: wing of atlas
Caudal-most: distal spine of scapula
Action: pull thoracic limb cranially and depress head/neck laterally
Trapezius
Origin: dorsal neck and dorsal thorax
Insertion: spine of scapula
Action: elevate thoracic limb
Rhomboideus
Origin: dorsal neck (cervicis), dorsal thorax (thoracis), nuchal crest of occipital bone (capitis)
Insertion: dorsal border of scapula and scapular cartilage
Action: elevate thoracic limb
Serratus ventralis
Origin: cervical vertebrae and thoracic wall of ribs
Insertion: serrated face of scapula
Action: support and elevate trunk
Latissimus dorsi
Origin: thoracolumbar fascia
Insertion: teres major tuberosity
Action: draw thoracic limb caudally, flex/extend humeral joint
Sternocephalicus
Origin: sternum
Insertion: mastoid process and occipital bone
Action: depress head and neck, draw them laterally
Sternohyoideus
Origin: sternum
Insertion: basihyoid
Action: pull tongue and larynx caudally
Sternothyroideus
Origin: cranial aspect of sternum
Insertion: thyroid cartilage
Action: pull tongue and larynx caudally
Deltoideus
Origin: spine of scapula and acromion
Insertion: deltoid tuberosity
Action: flex humeral joint
Supraspinatus
Origin: supraspinous fossa
Insertion: greater tubercle
Action: extend humeral joint
Subscapularis
Origin: subscapular fossa
Insertion: lesser tubercle
Action: adduct limb
Infraspinatus
Origin: infraspinous fossa
Insertion: greater tubercle
Action: flex humeral joint, abduct limb
Teres major
Origin: caudal border of scapula
Insertion: teres major tuberosity
Action: flex humeral joint
Biceps brachii
Origin: supraglenoid tubercle
Insertion: radial and ulnar tuberosity
Action: flex cubital joint and extend humeral joint
Brachialis
Origin: brachial groove
Insertion: proximal radius and ulna
Action: flex cubital joint
Triceps brachii
Origin: caudal border of scapula (long head), proximal humerus (all other heads)
Insertion: olecranon tuber
Action: flex humeral joint (long) and extend cubital joint (all other heads)
Extensor carpi radialis
Origin: lateral epicondyle
Insertion: dorsal base of 2 and 3 metacarpals
Action: extend carpal joints
Common digital extensor
Origin: lateral epicondyle
Insertion: extensor processes of distal phalanges
Action: extend carpal and digital joints
Lateral digital extensor (thoracic)
Origin: lateral epicondyle
Insertion: distal phalanges and/or proximal/medial lateral digits
Action: extend carpal and digital joints
Ulnaris lateralis
Origin: lateral epicondyle
Insertion: accessory carpal bone and lateral base of 5th metacarpal
Action: flex carpal joints, abduct manus
Supinator
Origin: lateral epicondyle
Insertion: body of radius
Action: supination of manus
Brachioradialis
Origin: lateral epicondyle
Insertion: fascia near carpus
Action: flexes cubital joint and supinates manus
Flexor carpi radialis
Origin: medial epicondyle
Insertion: palmar base of metacarpal bones 2 and 3
Action: flex carpal joints
Flexor carpi ulnaris
Origin: medial epicondyle and olecranon
Insertion: accessory carpal bone
Action: flex carpal joints
Superficial digital flexor (thoracic)
Origin: medial epicondyle
Insertion: palmar aspects of middle phalanges
Action: flex carpal joints, metacarpophalangeal and proximal interphalangeal joints
Deep digital flexor
Origin: medial epicondyle, radius, ulna
Insertion: flexor tubercles of distal phalanges
Action: flex carpal and digital joints
Pronator teres
Origin: medial epicondyle
Acton: weak elbow flexion and weak pronation of manus
Pronator quadratus
Attachments: apposed surfaces of radius and ulna
Action: pronation of manus
Interossei muscles
Origin: palmar base of metacarpal bone
Insertion: palmar base of proximal phalanges and tendon of common digital extensor
Action: flexes/supports metacarpophalangeal joint
Tensor fasciae latae
Origin: tuber coxae
Insertion: fascia lata
Action: tense fascia lata (flex coxal joint and extend genual joint)
Superficial gluteal
Origin: sacrotuberous ligament
Insertion: third trochanter
Action: abduct limb
Middle gluteal
Origin: gluteal surface of ilium
Insertion: greater trochanter
Action: extend coxal joint, abduct limb
Deep gluteal
Origin: body of ischium and ischiatic spine
Insertion: greater trochanter
Action: extend coxal joint
Piriformis
Origin: sacrum and 1st caudal vertebra
Insertion: greater trochanter
Action: extend coxal joint
External obturator
Origin: ventral aspect of os coxae around obturator foramen
Insertion: trochanteric fossa
Action: rotate limb laterally at coxal joint
Internal obturator
Origin: dorsal aspect of os coxae around obturator foramen
Insertion: trochanteric fossa
Action: rotate limb laterally at coxal joint
Gemelli
Origin: lateral aspect of ischium
Insertion: trochanteric fossa
Action: rotate limb laterally at coxal joint
Quadratus femoris
Origin: ventral aspect of ischium
Insertion: caudal femur near trochanteric fossa
Action: extend coxal joint, rotate limb laterally at coxal
Biceps femoris
Origin: ischiatic tuberosity and sacrotuberous ligament
Insertion: patella, tibia, tuber calcanei
Action: extend coxal joint, extend tarsocrural joint, variable on genual
Semitendinosus
Origin: ischiatic tuberosity
Insertion: tibia and tuber calcanei
Action: extend coxal joint, variable on genual, extend tarsocrural joint
Semimembranosus
Origin: on/near ischiatic tuberosity
Insertion: distal femur and proximal tibia
Action: extend coxal joint, variable on genual
Gracilis
Origin: pelvic symphysis
Insertion: medial aspect of genual region
Action: adduct limb, extend coxal joint, flex genual joint, extend tarsocrural joint
Sartorius
Origin: crest of ilium
Insertion: medial aspect of genual region
Action: flex coxal joint, extend genual joint (cranial) and flexes genual joint (caudal)
Pectineus
Origin: iliopubic eminence
Insertion: distal body of femur
Acton: adduct limb
Adductor
Origin: ventral surface of os coxae
Insertion: caudal surface of femur
Action: adduct limb and extend coxal joint
Quadriceps femoris
Origin: ilium (rectus femoris) and proximal femur for the other 3
Insertion: tibial tuberosity
Action: flex the coxal joint (rectus femoris), other 3 extend the genual joint
Iliopsoas
Origin: ilium and lumbar vertebrae
Insertion: lesser trochanter
Action: flex coxal joint
Cranial tibial
Origin: lateral aspect of proximal tibia
Insertion: plantar base of metatarsal bones 1 and 2
Action: flex tarsocrural joint
Long digital extensor
Origin: extensor fossa
Insertion: extensor processes of distal phalanges
Action: extend genual joint, flex tarsocrural joint, extend digital joints
Lateral digital extensor (pelvic)
Origin: on/near proximal aspect of fibula
Insertion: lateral digits
Action: flex tarsocrural joint and extend digital joint
Peroneus longus
Origin: on/near lateral collateral ligament
Insertion: plantar base of metatarsal bones
Action: flex tarsocrural joint
Gastrocnemius
Origin: distal caudal femur
Insertion: tuber calcanei
Action: flex genual joint and extend tarsocrural joint
Superficial digital flexor (pelvic)
Origin: lateral supracondylar tuberosity
Insertion: tuber calcanei and bases of middle phalanges
Action: flex genual joint, extend tarsocrural joint, flex metatarsophalangeal and proximal interphalangeal joints
Deep digital flexor (pelvic)
Origin: proximal caudal aspect of tibia and fibula
Insertion: flexor tubercle of distal phalanges
Action: extend tarsocrural joint, flex digital joints
Popliteus
Origin: popliteal fossa
Insertion: proximal caudal aspect of tibia
Acton: sensory function for genual joint
