Equine Proximal Thoracic Limb Flashcards
Notable bony prominences scapula
scapular spine supraspinous fossa infraspinous fossa scapular notch supraglenoid tubercle scapular cartilage
scapular spine
lateral aspect in middle of scapula
supraspinous fossa
on cr lateral aspect of scapula, supraspinatus attaches to this
infraspinous fossa
on cd lateral aspect of scapula, infraspinatus attaches to this
supraglenoid tubercle
cr scapula, wedge like, on thin side of scapula, adjacent to scapular notch
- biceps brachii attaches here
scapular notch
on dorsal aspect of scapula, cr, adjacent to superglenoid tubercle (starts around narrowing of scapula)
scapular cartilage
on dorsal aspect of scapula on wide end; can become ossified
notable bony landmarks of humerus
greater tubercle
lesser tubercle
intermediate tubercle
medial and lateral epicondyles
notable bony landmarks of radius
medial and lateral styloid processes
notable bony process of ulna
- olecranon
- ulna is not complete in horse; the dorsal remnant of the the ulna is the lateral styloid process
greater tubercle of the humerus
lateral, has cr and cd part; cr part is pt of shoulder
lesser tubercle of the humerus
on medial side of humerus
intermediate tubercle of humerus
on dorsal aspect of humerus between greater and lesser tubercle
- biceps runs through groove divided by this
- teres major attaches here
what attaches to greater tubercle of the humerus
supraspinatus and infraspinatus
what attaches to the lesser tubercle of the humerus
supraspinatus and subscapularis
medial and lateral epicondyles of the humerus
on the ventral aspect of the humerus; will see jutting out of bone that is fairly rounded this is epicondyle
what attaches to lateral epicondyle of humerus
extensors of the carpus and digit
- Extensor carpi radialis
- common digital extensor
- Lateral digital extensor
- extensor carpi ulnaris
- all innervated by radial nerve
what attaches to medial epicondyle of humerus
flexors of the carpus and digit
- flexor carpi ulnaris
- Superficial digital flexor
- deep digital flexor
- flexor carpi radialis
- all innervated by mixed innervation from median and ulnar nerves
medial and lateral styloid processes
bony prominences of the radius
- on v surface (distal) of radius circular almost pointy looking bump of bone
- distal attachment points lateral ligaments?
olecranon
triceps brachii inserts here; this is the elbow
deltoid tuberosity
lateral on humerus; located mid bone
what attaches to deltoid tuberosity
deltoideus; teres minor attaches just proximal to deltoid tuberosity
carpal bones
accessory carpal bone, ulnar carpal bone, intermediate carpal bone, radial carpal bone, carpal bones 2,3, and 4
accessory carpal bone
located along back of carpus (cd aspect)
radial carpal bone
dorsal row, medial
intermediate carpal bone
dorsal row, between radial and ulnar carpal bones
ulnar carpal bone
dorsal row, lateral
carpal bones 2,3,4
2 v small v medial almost looks continuous with 3 grossly bt not on rad; 4th is lateral
what attaches to accessory carpal bone
- extensor carpi ulnaris short tendon
- flexor carpi ulnaris distal attachment
blood supply hind limb
- axillary
2a. subscapular
2b. Brachial
3b. Median
4b. Medial and lateral palmar
4bb. Medial and lateral palmar metacarpal
5b. Medial and lateral palmar digital
suprascapular nerve
innervates muscles sitting cr to spine of scapula aka lateral shoulder stabilizers (supraspinatus and infraspinatus); dives between subscapularis and infraspinatus
axillary nerve
innervates shoulder flexors (teres major and deltoideus; also innervates teres minor which is lateral stabilizer of shoulder not flexor); dives between supscapularis and teres major
subscapular nerve
innervates subscapularis; stays on medial side of shoulder
musculocutaneous
innervates elbow flexors (biceps brachii and brachialis); travels down brachium
radial nerve
innervates elbow extensors (triceps brachii) and carpal and digital extensors (extensor carpi radialis, common digital extensor, lateral digital extensor, extensor carpi ulnaris); weight bearing nerve of forelimb
median and ulnar nerves
innervate digital flexors (flexor carpi ulnaris, flexor carpi radialis, superficial digital flexor, deep digital flexor)
innervation distal limb thoracic limb
median and ulnar nerves
median nerve
- Median nerve
2a. Medial palmar nerve
3a. Communicating branch
2b. Lateral Palmar nerve
3b. Deep branch
4b. Medial and lateral palmar metacarpal nerves
2c. Medial and lateral palmar digital nerves
ulnar nerve
palmar brach blends with lateral palmar nerve
components of the passive stay apparatus do what
Overall goal is minimal energy expenditure (ligaments and tendons, want to extend every jt not flex bc flex = buckled)
- Avoid shoulder flexion
- Avoid carpal and elbow flexion
- Avoid carpal overextension
- Avoid pastern and fetlock overextension
What structure(s) avoids shoulder flexion
-Biceps brachii tendon
what structure(s) avoid carpal and elbow flexion
- Lacertus fibrosis
- extensor carpi radialis
- collateral ligaments
what structure(s) avoid carpal overextension
- palmar carpal ligament