Canine Forelimb Extrinsic Muscles

Cutaneous trunci (origin)

Superficial fascia of trunk

Cutaneous trunci (insertion)

Caudal border of deep pectoral and fascia of medial antebrachium

Cutaneous trunci (action)

Twitch skin

Cutaneous trunci (innervation)

Lateral thoracic nerve

Cutaneous trunci (arterial supply)

Lateral thoracic artery

Superficial pectoral (origin)

1st and 2nd to 3rd sternebrae

Superficial pectoral (insertion)

crest of greater tubercle of humerus

Superficial pectoral (action)

adduct limb when not bearing weight, prevent abduction when bearing weight

Superficial pectoral (innervation)

Ventral branch of spinal nerves C7 and C8, Cranial pectoral nerves

Superficial pectoral (arterial supply)

External thoracic artery

Deep pectoral (origin)

Ventral part of sternum

Deep pectoral (insertion)

lesser and greater tubercles of the humerus

Deep pectoral (action)

Pull trunk cranially and extend shoulder joint when supporting weight, draw limb caudally and flex shoulder when not SW

Deep pectoral (innervation)

Caudal pectoral nerves, C8, and T1

Deep pectoral (arterial supply)

Lateral thoracic artery

Platysma (origin)

Deep raphe of the neck

Platysma (insertion)

Cheek and commissure of labia

Platysma (action)

Draw lips caudad

Platysma (innervation)

Facial nerve

Brachiocephalicus (origin)

Clavicular intersection

Cleidobrachialis (insertion)

cranial border of humerus, distal

Cleidocephalicus (insertion)

cranial half of the mid-dorsal fibrous raphe/temporal bone (mastoid part)

Brachiocephalicus (action)

advance limb, extend shoulder, laterally flex neck

Brachiocephalicus (innervation)

accessory nerve and ventral branches of cervical spinal nerve

Brachiocephalicus (arterial supply)

superficial cervical artery

Sternocephalicus (origin)

1st sternebra/manubrium

Sternocephalicus (insertion)

Temporal bone (mastoid part) and occipital bone (nuchal crest)

Sternocephalicus (action)

Draw head and neck to side

Sternocephalicus (innervation)

Accessory nerve and ventral branches of cervical spinal nerves

Sternocephalicus (arterial supply)

Superficial cervical artery

Sternohyoideus (origin)

1st sternebra, 1st costal cartilage

Sternohyoideus (insertion)

Basihyoid bone

Sternohyoideus (action)

Pull tongue and larynx caudally

Sternohyoideus (innervation)

Ventral branches of cervical spinal nerves

Sternohyoideus (arterial supply)

Superficial cervical artery

Sternothyroideus (origin)

1st costal cartilage

Sternothyroideus (insertion)

Caudolateral surface of thyroid cartilage

Sternothyroideus (action)

Draw larynx and tongue caudally

Sternothyroideus (innervation)

Cervical spinal nerves, hypoglossal nerve

Sternothyroideus (arterial supply)

Superficial cervical artery

Omotransversarius (origin)

Distal spine of scapula

Omotransversarius (insertion)

Wing of the atlas

Omotransversarius (action)

Advance limb, flex neck laterally

Omotransversarius (innervation)

Accessory nerve

Omotransversarius (arterial supply)

Superficial cervical artery

Trapezius (Origin)

Median raphe and supraspinous ligament from C3 to T9

Trapezius (insertion)

spine of scapula

Trapezius (action)

elevate and abduct forelimb

Trapezius (innervation)

Accessory nerve

Trapezius (arterial supply)

Superficial cervical artery

Rhomboideus (origin)

capitis: nuchal crest of occipital bone; cervicis: median fibrous raphe of neck; thoracis: spinous process of T1-T7

Rhomboideus (insertion)

Dorsal border of scapula

Rhomboideus (action)

Elevate limb, draw scapula to trunk

Rhomboideus (innervation)

Ventral branches of cervical and thoracic spinal nerves

Rhomboideus (arterial supply)

Superficial cervical artery

Latissimus dorsi (origin)

Thoracolumbar fascia

Latissimus dorsi (insertion)

Teres major tuberosity and teres major tendon

Latissimus dorsi (action)

Draw free limb caudal (digging), flex shoulder joint

Latissimus dorsi (innervation)

Thoracodorsal nerve (C7, C8, T1)

Latissimus dorsi (arterial supply)

Lateral thoracic artery, thoracodorsal artery

Serratus ventralis (origin)

transverse processes of C3-C7 and ventral halves of ribs 1-7

Serratus ventralis (insertion)

Serrated face of scapula

Serratus ventralis (action)

Support trunk, depress scapula

Serratus ventralis (innervation)

Cervical spinal nerve, long thoracic nerve

Serratus ventralis (arterial supply)

Superficial cervical artery