Thoracic Limb - Bones

Name these parts of the humerus

1. lesser tubercle 2. medial epicondyle 3. trochlea 4. capitulum 5. lateral epicondyle 6. deltoid tuberosity 7. greater tubercle

Name these parts of the humerus

1. greater tubercle 2. tricipital line 3. deltoid tuberosity 4. lateral epicondyle 5. olecranon fossa 6. medial epicondyle 7. supratrochlear foramen 8. lesser tubercle 9. head 10. body of humerus

Name these parts of the humerus

1. head 2. lesser tubercle 3. teres major tuberosity 4. medial epicondyle 5. greater tubercle 6. intertubercular groove 7. capitulum 8. trochlea

name these parts of the humerus

1. greater tubercle 2. head 3. tricipital line 4. deltoid tuberosity 5. body 6. brachial groove 7. radial fossa 8. lateral supracondylar crest 9. lateral epicondyle

Name these parts of the scapula

1. supraglenoid tubercle 2. glenoid cavity 3. acromion 4. spine 5. supraspinous fossa 6. infraspinous fossa 7. coracoid process 8. glenoid cavity 9. serrated face 10. subscapular fossa

Name these parts of the ulna

1. anconeal process 2. trochlear notch 3. medial coronoid process 4. lateral styloid process 5. olecranon 6. tuber olecrani

Name these parts of the ulna

1. tuber olecrani 2. olecranon 3. lateral coronoid process 4. radial notch 5. lateral styloid process 6. medial coronoid process 7. trochlear notch 8. anconeal process

Name these parts of the radius

1. head 2. neck 3. ulnar notch 4. medial styloid process

Name these parts of the radius

1. head 2. neck 3. medial styloid process

Name these parts of the manus

1. radius 2. ulna 3. intermedioradial carpal 4. ulnar carpal 5. distal phalanges 6. proximal phalanges 7. middle phalanges

Name these parts of the manu

1. radius 2. intermedioradial carpal 3. ulna 4. accessory carpal 5. ulnar carpal

What is a useful landmark for arthrocentesis of the shoulder joint and detection of shoulder luxations?

The acromion

What is special about the clavicle of cats?

it is more developed and palpable

What is special about the acromion in cats?

it exhibits both a hamate (distal) and suprahamate (proximal) process

What is unique about the scapula in cats?

the dorsal border normally projects above the spinous processes of the thoracic vertebrae

what is special about the coracoid process in cats?

it is well developed

What is a common site of osteochondritis dissecans lesions and flexion of the shoulder joint?

The caudal aspect of the humeral head.

• These diseases are painful

  • the greater tubercle is preferred for collection of bone marrow for samples/grafts

what is a common site for articular fractures?

the humeral condyle

Do cats have a supratrochlear foramen?

No, they have a supracondylar foramen.

• the brachial a. (not v.) and median n. travel through this

  • these are vulnerable to injury in distal humeral fractures and must be considered in humeral repair

What on the ulna is prone to avulsion fractures?

the olecranon, due to its attachment to the triceps.

What happens during elbow luxation?

the palpable olecranon is displaced laterally to the lateral epicondyle (also palpable).

what is the important of the anconeal process in immature dogs?

it’s a separate ossification center. If not fused in time, ununited anconeal process (UAP) develops, leading to degenerative joint disease (arthritis) of the elbow

What else can lead to degenerative joint disease in dogs?

Fragmentation of the medial coronoid process. Pressure over the medial aspect of the elbow elicits pain in this condition.

what is a landmark during declawing?

The ungual crest. Failure to remove it completely will result in regrowth of the claw.

What does cats have on their distal phalanx?

Dorsal elastic ligaments, which keep the claw in a retracted state.

• in retraction, the distal phalanx lies lateral to the middle phalanx

• upon flexion of the deep digital flexor muscle/tendon, the claw is exposed

  • arrangement of the distal phalanx is important during declaws

what is the carpal organ?

In cats, they have specialized sensory elevation in the skin on the caudal forearm. This area has stiff whiskers connected to pressure receptors. Not to be confused with a tumor/lesion.

what are the 4 regions of the forelimb?

1. shoulder

2. brachium

3. antebrachium

   1. manus

what is the difference in forelimbs between a cat and a dog?

The bumps, holes, and depressions are more prominent in dogs. Cat bones are usually straighter

does the shoulder articulate with the trunk?

no, extrinsic muscles attach the forelimb to the bodyw

what other animals have a suprahamate process?

elephants and rabbits

what runs through the supratrochlear foramen in dogs?

nothing

What is OCD?

Osteochondritis Dissecans

• The term osteochondrosis refers is an abnormal development of the cartilage on the end of a bone in the joint.

  • OCD occurs when the diseased cartilage separates from the underlying bone. It most commonly affects the shoulder joint, but the elbow, hip, or knee (stifle) may also be affected.

what percent of weight do the radius and ulna support?

radius - 80% ulna - 20%

at what ages. do more fractures occur in dogs?

when they’re immature

What can result from forces transmitted through the limb?

it can break off the lateral aspect of the humeral condyle

what do the radius/ulna allow for?

pronation/supination

• ulna starts medially and ends up laterally

• a fracture of one likely means a fracture to both

what is a physis?

a growth plate

describe the guillotine declaw method. is it optimal?

• Have to control hemostasis – tourniquets (possible radial n. damage if left on too long)

• Pressure bandages for several days

• Often get part of pad – disfigured/pain

• Leave behind bone (P3) – possibility of claw regrowing/pain

• Higher incidence of chronic lameness

• not optimal

describe the scalpel declaw method

• surgical removal w/ scalpel blade

• Have to control hemostasis – tourniquets

• Pressure bandages for several days

• More precise removal of P3/no bone left over

• Little to no regrowth

• Lower incidence of chronic pain/lameness

describe the laser declaw method

• Similar to scalpel technique, just use laser

• Usually little bleeding – no tourniquet

• Need to prevent burning

• More precise removal of P3/no bone left over

• Little to no regrowth

• Lower incidence of chronic pain/lameness

  • Expensive piece of equipment/training

do muscles act on bones or joints?

joints. muscles must cross over the act on it

what is the appendicular skeleton?

includes the limbs and girdles that attach them to the axial skeleton

what is the axial skeleton?

forms the body axis and protects vital organs