Thoracic Limb- Myology Flashcards
Rhomboid
Origen: nuchal ligament from 2-6th cervical vertebra to 7th thoracic vertebra
Insertion: medial surface of dorsal border of scapula
Innervation: cervical and thoracic spinal nerves
Function: draws limb forward, fixes scapula, elevates limb and neck
Which are the extensor muscles of the digits?
Common digital extensor
Lateral digital extensor
Long abductor muscle of the 1st digit
Extensor muscle of the 1+nd digit
Brachialis
Origin: caudal neck of humerus
Insertion: proximal cranial surface of radius/ulna
Innervation: radial and musculocutaneous nerve
Function: flexion of elbow joint
Biceps brachii
Origin: supraglenoid cavity
Insertion: radial tuberosity
Innervation: musculocutaneous nerve
Function: flexion of elbow joint, extension of shoulder joint, fixes shoulder
Subscapular
Origin: subscapular fossa
Insertion: lesser tubercle
Innervation: subscapular nerve
Function: extensor or flexor of shoulder, fixes shoulder joint
Radial extensor muscle of the carpus
Origin: lateral epicondyle of humerus
Insertion: 3rd metacarpal bone
Innervation: radial nerve
Function: extension of carpus
What are the general characteristics of the fixation muscles of scapula?
Fixes thoracic limb to the trunk
Origins in neck or back
Insertion in scapula and forearm
Innervated by accessory nerve to r dorsal branches are f cervical and thoracic spinal nerves
Latissimus dorsi
Origin: thoracolumbar fascia
Insertion: caudal border of scapula, lateral surface of thorax and body of humerus
Innervation: thoracodorsal nerve
Function: main retroversr of thoracic limb, flexor of shoulder
Brachiocephalic
Origins at head, different between species
Insertion: as cleidobrachialis, differs between species
Innervation: accessory nerve, axillary nerve, cervical nerve
Function: draws neck and head down/back, draws head/neck/ upper arm fascia to one side
Infraspinous
Origin: infraspinous fossa
Insertion: greater tubercle of humerus
Innervation: suprascapular nerve
Function: flexion and fixation of shoulder joint
Quadrate pronator
Origin: ulna
Insertion: radius
Innervation: median nerve
Function: pronation
Which are the fixation muscles of the scapula?
Trapezius
Omotransverse
Rhomboid
Ventral serrate
Ulnar extensor of the carpus
Origin: lateral epicondyle of humerus
Insertion: 4+5+accessory metacarpal bones
Innervation: radial nerve
Function: flexion carpus, supports extension of carpus
Radial flexor muscle of the carpus
Origin: medial epicondyle of humerus
Insertion: 2+3rd metacarpal bones
Innervation: median nerve
Function: flexion of carpus
Major teres
Origin: caudal border of scapula
Insertion: tuberosity for teres major
Innervation: axillary nerve
Function: flexion of shoulder joint
Sternocephalic
Origin: manubrium
Insertion: head, differs between species
Innervation: ventral branch of accessory nerve
Function: flexor of head/neck, draws head/neck to the side, fixes head during swallowing
Coracobrachialis
Origin: coracoid process of scapula
Insertion: medial surface f humerus
Innervation: musculocutaneous nerve
Function: extensor of shoulder joint, adductor of thoracic limb
Which are the superficial extrinsic muscles?
Brachiocephalic Sternocephalic Trapezius Omotransverse Latissimus dorsi Superficial pectoral
Deltoid
Origin: scapula spine and caudal border of scapula
Insertion: deltoid tuberosity
Innervation: axillary nerve
Function: flexion of shoulder joint, abduction of thoracic limb
Ulnar flexor muscle of the carpus
Origin: medial epicondyle of humerus
Insertion: carpal bones
Innervation: ulnar nerve
Function: flexion of carpus
What are the general characteristics of the intrinsic muscles of the thoracic limb?
Responsible for movements of separate parts of the limb
Trapezius
Origin: nuchal ligament/supraspinous ligament
Insertion: scapula spine
Innervation: accessory nerve (dorsal branches)
Function: fixes shoulder joint, lifts/abducts and draws limb forward
Supinator
Origin: lateral epicondyle of humerus
Insertion: radius
Innervation: radial nerve
Function: supination
What are the general characteristics of the extensor muscles of the digits?
Cranial-lateral surface
Origin: lateral epicondyle of humerus, radius/ulna
Insertion: digits
Innervation: radial nerve
Which are the deep extrinsic muscles?
Deep pectoral
Subclavian
Rhomboid
Ventral serrate
What are the muscles of the elbow joint?
Brachialis Biceps brachii Triceps Anconeous Tensor muscle of antebrachial fascia
What are the muscles of the shoulder joint lateral surface?
Supraspinous
Infraspinous
Deltoid
Minor trees
What are the general characteristics of the flexor muscles of the digits?
Medial-palmar surface
Origin: medial epicondyle of humerus, radius/ulna
Insertion: digits
Innervation: ulnar and median nerve
Supraspinous
Origin: supraspinous fossa of scapula
Insertion: greater and lesser tubercle of humerus
Innervation: suprascapular nerve
Function: extension and fixation of shoulder joint
Triceps
Origin: caudal border of scapula or humerus
Insertion: olecranon of ulna
Innervation: radial nerve
Function: extension of elbow joint, flexion of shoulder
Articular muscle of the shoulder joint (equine, pigs, cats)
Origin: glenoid cavity of scapula
Insertion: neck of humerus
Innervation: axillary nerve
Function: tenses joint capsule
What are the muscles of the shoulder joint medial surface?
Major teres
Articular muscle of shoulder joint
Subscapular
Coracobrachial
Round pronator
Origin: medial epicondyle of humerus
Insertion: radius
Innervation: median nerve
Function: pronation
Superficial pectoral
Origin: sternal manubrium
Insertion: humerus
Innervation: thoracic and pectoral spinal nerves
Function: anteversor and retroversir of thoracic limb and lateral movement of trunk
What are the general characteristics of the superficial extrinsic muscles?
Origins in neck, back and then radical region
inserts in scapula and humerus
Joins the limb to the trunk, responsible for coordinating movements of the head, neck, limb and trunk
What are the muscles of the carpal joints?
radial extensor muscle of carpus
Ulnar extensor muscle of carpus
Radial flexor muscle of carpus
Ulnar flexor muscle of carpus
Deep pectoral
Origin: sternum
Insertion: lesser tubercle of humerus
Innervation: thoracic spinal nerves
Function: retroversor thoracic limb, adductor, fixes limb to trunk
Anconeus
Origin: olecranon fossa and humerus
Insertion: olecranon
Innervation: radial nerve
Function: extension of elbow joint
Tensor muscle of antebrachial fascia
Origin: caudal border of scapula
Insertion: antebrachial fascia
Innervation: radial nerve
Function: extension of shoulder joint, tenses antebrachial fascia
Brachioradial
Origin: humerus
Insertion: radius
Innervation: radial nerve
Function: supination
Which are the flexor muscles of the digits?
Superficial digital flexor muscle
Deep digital flexor muscle
Interflexor muscle
What are the muscles of the radioulnar joint?
Supinator muscles: brachioradial, supinator
Pronator muscles: round pronator, quadrate pronator
Minor teres
Origin: caudal border f scapula
Insertion: tuberosity for teres minor
Innervation: axillary nerve
Function: flexion of shoulder joint
Omotransverse
Origin: wings of atlas or transverse process of 2nd cervical vertebra
Insertion: scapula spine
Innervation: accessory nerve
Function: draws neck backwards/sideways, draws scapula forward
Ventral serrate
Origin: cervical portion: cervical transverse processes, thoracic portion: ribs lateral surface
Insertion: medial surface of scapula/serrate surface
Innervation: cervical and thoracic spinal nerves, long thoracic nerve
Function: draws limb forward, fixes scapula, elevated limb and neck
