Bones Flashcards
Hard, semi-rigid, calcified connective tissue
forming the skeleton
Bones
Found mainly in the
limbs
Has a body/shaft
called diaphysis and
two ends called the
epiphyses
Long bones (ossa longa)
Carpal (wrist), tarsal
(ankle)
Associated with the
spread of pressure
exerted in these
regions
Sesamoid bones
short bones (ossa brevis)
Found in the
thoracic and pelvic
girdles and in the
head
Weigh less
Flat bones (ossa plana)
Vertebral column
and bones of the
skull
For muscular and
ligamentous
attachment
With projecting
processes
Irregular bones (ossa
iregulata)
2 forms of bones based on
structure
Cancellous or
spongy bone
Compact bone
epiphyses in young:
epiphyseal
plate
hollow portion of long bones
Medullary cavity
Young
red marrow
Adult
red and yellow
marrow (fat)
compact bone
surrounding the shaft of
the long bone
Cortex
Layer of specialized connective tissue covering
the outer surface of the bone
Periosteum
thin fibrous membrane that lines the medullary
cavity and osteonal (Haversian) canals of a bone
Endosteum
Inflammation of the
growth plates in the
long bones of
growing foals
Physitis / physeal dysplasia
3 Major Groups of the
Skeletal System
Axial
Appendicular
Visceral
Skull, vertebral column, ribs & sternum
Axial
Thoracic & pelvic limbs
Appendicular
Baculum or os penis (dogs) , ossa cordis (ox and sheep),
os rostri (pigs)
Visceral
Common sites of luxation in horses:
- stifle/patella
- hock
- fetlock
- pastern
A relatively common
developmental disease that
affects the cartilage and bone in
the joints of horses.
It causes clinical signs of disease in 5-25% of all horses and can occur in all horse breeds.
Osteochondritis dissecans (OCD)
Osteochondrosis
Common sites of osteochondrosis : Horse
- Shoulder
- Stifle
- Hock
- Fetlock
Common sites of osteochondrosis : Ox
- Poll/Pin bones
- Shoulder (Proximal end of the humerus)
- Elbow (Distal end of the ulna)
- Stifle
Osteochondrosis in Dogs
common in giant & large breeds
(ie Great Dane, Labrador, Rottweilers)
Osteochondrosis in Cattle
male, purebred
Weight distribution of
horse
Forelimb 58%
Hindlimb 42%
Average horse weight: 1,050 lbs or 476.272 kgs
Weight distribution of ox
Forelimb 60%
Hindlimb 40%
Average ox weight: 1,390 lbs or 630.4934 kgs
Bony orbit: complete
horse and ruminants
Bony orbit: incomplete
carnivores but is completed by the orbital ligament
Facial crest
horses - the ridge on the lateral surface of the face
Facial tuberosity
ruminants - the process on the lateral surface of the face
Cornual process
horned ruminants - the process of the frontal bone of the horned ruminants that is enclosed by the horn
Temporal fossa
ruminants
pushed to the lateral side of the skull by the frontal bone
Foramen orbitorotondum
ruminant and pig
joining of the round and orbital foramina of other species
Interparietal bone
horses and cats
Frontal & Rostral bones (Pre-nasal)
Pig - os rostri
Cephalic index (CI)
The ratio of the maximum width of the head (A) multiplied by 100 divided by the head’s maximum length (B)
Dolichocephalic
CI < 50
Mesocephalic
50 < CI < 60
Brachycephalic
60 < CI = Short-headed
localized, chronic, progressive, granulomatous abscess that most frequently involves the mandible, the maxillae, or other bony tissues in the head
“Lumpy Jaw” or
Actinomycoses
Actinomycoses bovis
treatment of choice in
ruminant actinomycosis.
sodium iodide
Paranasal sinuses
Frontal sinus
Cornual Diverticulum
Conchofrontal sinus &
Frontomaxillary opening
horse
Maxillary recess
dog
Rostral & caudal maxillary
sinus
Horse
Insertion of lavage systems for treatment of primary sinusitis
Sinuscopy
Trephination
Lacrimal bulla
(ruminants)
HYOID APPARATUS
Stylohyoid bone
Epihyoid bone
Ceratohyoid bone
Basihyoid bone
Thyrohyoidbone
Stylohyoid bones are not palpable.
Carnivores
Epihyoid is small, the lingual process is present and they
have a well developed stylohyoid muscle.
Equine
Lingual process is present.
Ruminants, Porcine
have 5-7 neck vertebrae
Two-toed sloths (Choloepus)
have 8 or 9 neck vertebrae
Three-toed sloths (Bradypus)
has 6 cervical
vertebra
manatee
Caused by stenosis of cervical
vertebral canal causing in a
“lazy” or “drunk”-like walk of
horses
Wobbler Syndrome, Equine
Sensory Ataxia (Canine
Wobbler in dogs)
Overriding spinous process,
affected bone is removed in triangular shaped wedges
Horse
Clavicle is separate, non-articulating bone
Cat
rudimentary clavicle
Dog
Clavicle is absent
Horse and Ox
Absent acromion
horse and pig
Spinal tuber – bony enlargement of the scapular spine
horse and pig
Scapular cartilage – narrow band in the dog
In ungulates, the dorsal border is extended by a scapular
cartilage, which enlarges the area for muscle attachment.
This ossifies with age.
Cat also possesses a _____ which lies proximal to the acromion and projects caudally.
suprahamate process
Humerus meets the radius via trochlea
large animals
Humerus articulates with
the ulna medially via a trochlea and the radius laterally via a capitulum
dogs and cats
Varus
Bow-legged
Vagus
Knock kneed
Ulna - fuses with the radius: therefore these animals cannot supinate or pronate their forearm.
horse and ruminant
Radius - Ulna: not fused: allowing pronation and supination
carnivores and pig
Styloid process of ulna - the distal
epiphysis of the ___’s ulna is
fused with the radius, and in
essence becomes a part of the
radius.
horse
has the “generalized” carpus of the 8 bones
Pig
conforms to the generalized pattern of 8 bones
unless the 1st carpal bone is missing, or rarely if a fifth
one is present.
Horse
have 7 carpal bones due to fusion of the radial and intermediate carpal bones to form the dog’s
“radial” carpal bone.
Dog and cat
has 6 carpal bones. The 1st carpal bones is missing and the 2nd and 3rd carpal bones are fused.
Ruminant
: has 4 metacarpal bones. The 1
st metacarpal bone (McI) is
missing. Metacarpal bones II and V (McII and McV) are greatly reduced and don’t
bear weight. The weight is borne by metacarpals III and IV (McIII and McIV).
Pig metacarpal bones
has 3 metacarpal bones, the 1st and 5th are missing.
Horse metacarpal bones
the common name for the greatly reduced metacarpal bones II
and IV (McII and McIV). The splints end distally in small swellings called the “buttons of the splints”
Splint bones
the common name for the large metacarpal III (McIII). it is the
only metacarpal bone to articulate with the digit.
Cannon bone
2 metacarpal bones. The 1st and 2nd (McI and McII) are missing and the 3rd and 4th are fused.
Ruminant metacarpal bones
the common name forfused metacarpal bones III and IV.
Large metacarpal bone (cannon bone)
the common name for the greatly reduced metacarpal bone V (McV)
Small metacarpal bone
digits: 4 digits,2 weight-bearing and 2 non-weight-bearing. The 1st digit is missing.
The 2nd and 5th digits are vestiges (improbable to find) externally manifested as horny
dew claws behind the fetlock.
Ox
3rd and 4th digits: fully developed weight-bearing digits consisting of 3 phalanges and
3 sesamoid bones
Ox
the long pastern in the horse
Proximal phalanx
the short pastern
Middle phalanx
the coffin bone
Distal phalanx
the proximal at the metacarpophalangeal joint and one distal
interphalangeal joint for each digit
Sesamoid bones
digits: 4 digits, the 1st is missing. The 2nd and the 5th are reduced and do not bearweight and are called dew claws. They are fully formed except that they lack a distalsesamoid bone. The main digits (3rd and 4th) consist of 3 phalanges, 2 proximal sesamoids and 1 distal sesamoid.
Pigs
digits: one digit per limb supporting Mc III.
Horse
Amputation
of digit
Cattle
is a horseman’s term for osteoarthritis, or bony
arthritis, of the pastern and/or coffin joints—ringbonein
the pastern joint is called high ringbone, and in the coffin
joint low ringbone. Arthritis is any condition that causes
inflammation of the joint
Ringbone
a very common cause of ringbone
Osteoarthitis, also poor shoeing
ringbone around metacarpal/metatarsal bone
Osselets
Treatment for Ringbone
Shoeing and NSAIDs
Surgery
Buttress foot
Horse
an inflammation or
degeneration of the navicular
bone and its surrounding
tissues, usually on the front
feet.
Navicular disease in horse
is ossification of
the collateral cartilages of
the distal phalanx; it occurs
most often in the lateral
cartilage
Pedal osteitis / Sidebones
Pedal osteitis / Sidebones : It is most common in the forefeet of
heavy horses working on
hard surfaces
Repeated
concussion to the quarters
of the feet is purported to
be the cause.
Osteitis/ Sidebones treatment
Box rest
NSAIDs
Trochlear tubercle - the large prominence on the medial ridge of the patellar surface in the ____ The patella locks over this
surface when the stay apparatus is in use.
horse
Third trochanter is absent in
ruminants
the tibia and
fibula are not fused.
Carnivores and pig
the head of the fibula
fuses to the tibia.
Ruminants
the fibula is a reduced bone
that reaches only half way down the tibia.
Horse
have
7 tarsal bones
Carnivores and pigs
have 5 tarsal bones due to fusion of 4 bones to form 2 bones- centroquartal bone (fused central and 4th) and fused 2nd and 3rd
Ruminants
has six tarsal bones due to fusion of 2 bones
- fused 1st and 2nd
Horses
have 2 trochlea to their talus
Ruminant and pig
the 1st metatarsal bone is even more reduced than in the front limb and the 1st digit (dew claw) is often absent.
Carnivores
the 5th metatarsal bone is absent. A metatarsal sesamoid bone is present and is often called the “small metatarsal” or metatarsal II.
Ruminants
Injuries in horses
Knock down hip
Mid shaft fractures
a bony growth within the lower hock joint of horse or cattle
caused by osteoarthritis, and the degree of lameness that results can be serious enough to end a horse’s competitive career
Bone spavin
Vertebral formula of fowl skeleton
C13, T7, L+S14 & C5 = 39
The skull is divided into
two regions
- Rounded cranium
- Conical facial region
The shoulder girdle:
- Scapula
- Coracoid
- Clavicle (wishbone/furcula)
The wing
- The upper arm – or humerus
- The forearm – radius and ulna
- The manus or hand – carpus, metacarpus and digits
The pelvic girdle or hip bones
- Ileum
- Ischium
- Pubis or pin bone
The leg
- Femur or thighbone
- Tibia and fibia
- Pes or foot – tarsus, metatarsus and digits or toes