Canine Anatomy

Front 1

Caudal

Back 1

Toward the tail

Front 2

Cranial

Back 2

Toward the Head

Front 3

Rostral

Back 3

Toward the nose

Front 4

Dorsal

Back 4

Towards the back or spine

Front 5

Ventral

Back 5

towards the belly (underside)

Front 6

Proximal

Back 6

towards the body

Front 7

Distal

Back 7

Away from the body

Front 8

Lateral

Back 8

surface directed away from the median plane

Front 9

Medial

Back 9

towards the median plane

Front 10

Palmar

Back 10

the flexor aspect of the foot, below the carpus

Front 11

Plantar

Back 11

the flexor aspect of the foot, below the tarsus (hock)

Front 12

median plane

Back 12

a vertical plane passing through the body from nose tip to tail tip

Front 13

osteoblasts

Back 13

produce bony tissue

Front 14

osteoclasts

Back 14

eat away bony tissue

Front 15

Diaphysis

Back 15

shaft

Front 16

Epiphysis

Back 16

ends

Front 17

What makes up the skeleton

Back 17

Bones, Cartilage, Periosteum (covers surface of bone), Marrow – yellow (fat) and red (blood cell forming), Ligaments

Front 18

Vertebrae

Back 18

Cervical vertebrae: 7: C1 atlas supports the skull, C2 axis provides rotation

Thoracic vertebrae: 13 (compared to 18 in the horse)

Lumbar vertebrae: 7

Sacrum 3 (fused) – pelvis is attached

Coccygeal – tail: 2-23, depending on breed and if docked

Front 19

Osteochondritis Dissecans

Back 19

Affects large and giant breeds

A growth disorder in the long bones

Normally, cartilage is produced and is replaced by bone as the dog matures. A disruption in the blood supply interferes with the process and calcification does not follow cartilage growth; the cartilage continues to grow, leaving a thick layer of cartilage that is less resistant to mechanical stress . Cracks and crevices form in the abnormally thickened cartilage and fragments detach and lodge in the affected joint.

It presents as mild to moderate lameness that progresses in severity over time. It is especially seen after rest when the dog first gets up and walks. Pain is elicited when you extend the limb. It may or may not have joint swelling.Treatment: Conservative – weight control, exercise limitation, non-steroidal anti-inflammatory drugs (NSAIDS) –OR- Surgery- arthroscopy to remove the loose & diseased cartilage.Without treatment they will develop arthritis

Front 20

Panosteitis

Back 20

Inflammation of the growing bone

The normal process of bone degeneration & resorption fails (remember osteoclasts) resulting in excess thickening of bone. This increased bone density can be seen on x-ray in more advanced cases

Large breed dogs, esp. German Shepherd Dogs

Young growing dog

Risk factors:over nutritionShifting leg lameness – know what this means

Pain especially seen in the long bones: humerus of front leg and femor or tibia of hind leg. It seems to be unaffected by rest or exercise.

Self-limiting - gets better on its own, outgrow it

Treat with NSAIDS, usually better by 18-24 mo of age

Front 21

Elbow dysplasia

Back 21

Improper formation of the elbow leading to osteoarthritis and eventual joint degenaration

1. Ununited anconeal process (UAP)- radius grows longer than ulna

2. Fragmented medial coronoid process (FMCP) – ulna longer than radius

3. Osteochondrosis dissecans (OCD) of the distal end of the humerus (medial condyle)Young, rapidly growing dogs

Lameness, mild & intermittent- see stiff stilted gait- holds elbow close to chest.

Genetic trait influenced by environmental effects (excessive caloric intake, supplements)Treatment – surgery to correct bone malalignment

Front 22

Hypertrophic Osteodystrophy

Back 22

Disease of young, rapidly growing dogs, large or giant breeds

Calcified cartilage fails to be penetrated by vessels from the bone marrow – this tissue then dies leaving excess mineralization with calcium deposits

Painful swelling of the joints, usually multiple limbs involved – obvious swelling

Lameness comes on suddenly and lasts 2-3 weeks at a time.

Extremely painful and has a fever.

Dog lays down and is reluctant to move.

Cause unknown

Nutrition (too many calories, too much calcium)Some think it is due to a vit C deficiency but vit C supplementation is NOT recommendedBacteria?

Usually treat with steroids covered by antibiotics in case there is a bacterial componentIt is self-limiting like panosteitis.

Front 23

Hip Dysplasia

Back 23

Developmental disease involving malformation of the femoral head (ball) and the acetabulum of the pelvis (the socket)

Muscle laxity during growth

During growth the pelvic muscles must hold the ball of the femur into the acetabulum. If the muscle tone is inadequate or bone growth is more rapid than muscle growth then can get subluxation (a partial dislocation) which leads to abnormal wear and erosion of the joint cartilage with eventual flattening of the femoral head and shallow development of the acetabula

Genetic trait strongly influenced by environmental factorsMeaning overnutritionAffects most large breed dogs

See a swaying gait at the walk, a bunny hop at the run, loaded shoulders with atrophied hindquarters, they may prefer to sit to eat, can’t jump up into the truck

Front 24

Diagnosis of Hip Dysplasia: Orthopedic Foundation of America (OFA)

Back 24

Xrays at 2 years of age (2 views)The hip distended view. Have to be perfectly lined up with patella in the middle. Even head and shoulders have to be perfectly symmetrical. The dog is anesthetized for the procedure.

Rated by veterinary radiologists

Only those rated good or excellent can be registered by OFA

Important to ask for this when buying a puppy of a breed prone to hip dysplasia

No guarantee, just a probability

So this is to check the parents or diagnose an adult dog.

Front 25

Diagnosis of Hip Dysplasia: University of Pennsylvania Hip Improvement Plan (PennHIP)

Back 25

Evaluation conducted by a specially trained veterinarian

A distraction index is calculated based on comparison of radiographs (X-rays) of “compressed” hips and “distracted” hips

Must be done under anesthesia or heavy sedation

Pups can be certified as young as 16 weeks

Front 26

Treatment for hip dysplasia:

Back 26

Moderate consistent exercise encouraged. No jumping. Surgery:

1. pectineous tendonectomy (cut tendon)

2. pelvic osteotomy (ream out arthritis)

3. resection arthroplasty of femoral head (cut it off)

4. total hip = replacement. This is the best treatment

Front 27

Extensors

Back 27

extend a limb

Front 28

Flexors

Back 28

flex the limb

Front 29

Adductors

Back 29

muscles that pull a limb toward the middle of the body

Front 30

abductors

Back 30

muscles that pull a limb away from the center of an animal’s body

Front 31

Dog vital signs

Back 31

Temp: 101-102.5

Respiratory Rate: 10-34 breaths per minutePulse: Puppies up to 180 beats per minute Small dogs - 90-120 bpm Medium dogs – 70-110 bpm Large dogs – 60-90 bpm