Equine Musculoskeletal 2 Flashcards
What muscles make up thoracic sling?
serratus ventralis, trapezius, rhomboideus, pectoralis
What is the most important muscle in the thoracic sling?
serratus ventralis
Whart structure attaches to spinous processes of the vertebrae and serratus ventralis?
dorsal scapular ligament
What muscle is in the equine proximal thoracic limb that was not seen in the dog?
subclavius
Where does subclavius m. run?
cranial to supraspinatus
Where does subclavius attach?
fascia of supraspinatus and sternum
What does rupture of serratus ventralis cause?
falling of entire trunk, scapular cartilage becomes visible at the withers
Supraspinatus OIA
O: supraspinous fossa
I: greater and lesser tubercles of the humerus
A: extend and stabilize humeral joint
Infraspinatus OIA
O: infraspinous fossa
I: superficial tendon- greater tubercle of humerus (infraspinous bursa)
-deep tendon- on caudal eminence of greater tubercle
A: stabilize humeral joint
Deltoideus OIA
O: caudal border of scapula, aponeurosis which covers infraspinatus
I: deltoid tuberosity
A: flex humeral joint
Subscapularis OIA
O: subscapular fossa
I: lesser tubercle of humerus
A: stabilize humeral joint
Teres major OIA
O: caudal angle of scapula and adj. caudal border of scapula
I: teres major tuberosity of humerus
A: flex humeral joint
Biceps brachii OIA
O: supraglenoid tubercle
I: radial tuberosuty of radius, extensor carpi radialis via lacertus fibrosus
A: flex cubital joint, extend humeral joint
What is located between the tendon of the origin of biceps brachii and the intertubercular grooves of the humerus?
intertubercular bursa
What is the tendinous insertion of biceps brachii on the extensor carpi radialis m.?
lacertus fibrous
Lacertus fibrosus is part of the ______________
stay apparatus
What connects the tendon of the biceps brachii to the extensor carpi radialis?
lacertus fibrosus
Triceps brachii OIA
O: long head-caudal border of scapula
lateral head-deltoid tuberosity
medial head-medial aspect of the humerus
I: olecranon tuber
A: extend cubital joint, long head- flex humeral joint
What is the difference between equine and canine triceps brachii m?
3 vs. 4 heads
2 bursae of triceps brachii m.
subtendinous and subcutaneous
Craniolateral muscles of the antebrachium are commonly called
extensors
only muscle of the craniolateral antebrachium that flexes
ulnaris lateralis
List the craniolateral muscles
extensor carpi radialis, common digital extensor, lateral digital extensor, ulnaris lateralis
List the caudomedial muscles
Flexor carpi ulnaris, flexor carpi radialis, SDF, DDF
Extensor carpi radialis OIA + innervation
O: lateral supracondylar crest of humerus
I: metacarpal tuberosity of metacarpal III
A: extend and fix carpus and flex elbow joint
Innervation: radial n.
Common digital extensor OIA + innervation
O: lateral epicondyle of the humerus
I: Extensor process of distal phalanx and dorsal surface of P1+P2
A: extend carpus and digit, flex elbow
Innervation: radial n.
Lateral digital extensor OIA + innervation
O: lateral tuberosity of the radius, lateral collateral ligament of elbow
I: dorsal aspect of proximal phalanx
A: extend carpus and digit
Innervation: radial n.
Ulnaris lateralis OIA + innervation
O: Lateral epicondyle of humerus
I: short tendon- accessory carpal bone
long tendon- metacarpal bone IV
A: flex carpus
Innervation: radial n.
Flexor carpi ulnaris OIA + innervation
O: humeral head- medial epicondyle of humerus, ulnar head- olecranon
I: accessory carpal bone
A: flex carpus, extend elbow joint
Innervation: ulnar n.
Flexor carpi radialis OIA + innervation
O: medial epicondyle of humerus
I: metacarpal bone II
A: flex carpus, extend elbow
Innervation: median n.
SDF OIA + innervation
O: medial epicondyle of humerus and radius (check ligament)
I: flexor surfaces of P1+P2
A: flex digit (except distal interphalangeal joint) and carpus, extend elbow joint
Innervation: ulnar n.
What is the check ligament of SDF.
accessory ligament of SDF
DDF OIA + innervation
O: humeral head- medial epicondyle of humerus, ulnar head- olecranon, radial head- radius
I: flexor surface of P3
A: flex digit, carpus, extend elbow
Innervation: median and ulnar nn.
Where does the check ligament of the DDF attach?
palmar carpal ligament and metacarpal III
Suspensory ligament is AKA the ….
interosseous m.
4 areas of suspensory ligament
proximal, mid-body, branches, extensor branches
2 parts of suspensory apparatus
suspensory ligament, distal sesamoidean ligaments
Extensor branch of suspensory ligament fuses with
common digital extensor tendon
suspensory ligament splits into 2 halves and inserts ….
on proximal sesamoid bones
what is the stay apparatus
set of anatomical structures to allow rest standing up w/ little muscular effort
joints tend to ___ under the weight of the horse, thus the need for the stay apparatus
flex
biceps brachii tendon locks in places in the ….. and locks the ……. joint
intertubercular groove; humeral
what muscle contracts to sustain cubital joint
triceps brachii (medial heads)
What helps resist stretching of flexion of carpus
attachment of biceps tendon to extensor carpi radialis (lacertus fibrosus)
What stabilizes the distal joints
check ligaments
7 components of stay apparatus
biceps brachii tendon, triceps brachii, extensor carpi radialis & lacertus fibrosus, SDF & DDF mm., check ligaments, SDF & DDF tendons, distal sesamoid ligaments
