A27 Flashcards
1
Q
Hoof
A
provides protection and is formed by keratinization of epithelial layer and modification of the underlaying dermes.
Acts as a shock absorber
species with elastic nature of component may aid the return of blood to the heart
2
Q
epidermis
A
keratin is referred to as the horn, and makes up the outer surface of the hoof
3
Q
Chorium
A
connected to the underlying structures by subcutis – divided into 5 segments
4
Q
Wall
A
- Visible
- Medial, lateral and dorsal aspect
- Toe, quarter and heels
- 5-10mm thick – three layers
- Protection layer - Periople
- Intermediate
- Inner lamina – anchors the hoof to the bone
5
Q
cornary segement
A
- This is where the wall is created, grows in distal direction from the coronary dermis
- Many papillaes – creates lamellar papilla in wall
- Pigmentation, less deeper in the hoof = white line (melanocytes) important in ferriary
6
Q
periople
A
- Small band of soft tissue found over the proximal surface of the wall of the hoof
- Junction between wall and skin
- Forms the layer that keeps the underlying tissues moist
- In ruminants it forms a part of the joint between the hooves of the foot
7
Q
sole
A
- Concave, majority of the horses weight is transferred to the margin of the sole
- 10 mm in some species
- Keratin is more easily worn down
- Solar chorium
8
Q
frog
A
- Apex, body and crus
- Collateral sulcus between the frog and the sole
- Keratinized stratified squamos epithelium – a lot of water content
- Forces the wall outwards when bearing weight = hoof mechanism
- Circulation of blood around the hoof and back to the heart
9
Q
other structures with the hoof
A
Within the hoof capsule we have the distal phalanx (coffin) distal end of the middle phalanx (pastern) the distal interphalangeal joint and the navicular bone. Other structures:
- Ligaments
- Cartilage
- Digital cushion
- Common digital extensor tendon
- Digital flexor tendon
10
Q
ungular cartilages
A
- Extension of the distal phalanx (proc cartilagio)
- Securliy attached to the internal structures of the foot by ligaments that will extend between
- the medial and lateral cartilages to the distal and middle phalanx
- distal sesamoid bone
- digital cushion
11
Q
pcollateral ligaments
A
- stabilizes the dital interphalangeal joint
- medial and lateral
- connects
- distal end of p2 and proximal end of distal phalanx P3
12
Q
annular ligaments
A
- medial and lateral surface of P1
- most superficial structure in the region
- lies just beneath the skin
- fuses with the digital flexor tendon
- when the ligaments are inside the hoof it will merge with the fibrous attachment of ungual cartialges and digital cushion
- continuous with the digital flexor tendon and inserts on the coffin bone
13
Q
sesamoidean ligament
A
- makes sure the navicular bone is securly attached
- to the distal phalanx – distal sesamoidean ligament
- proximal phalanx – proximal interphalangeal collateral ligaments
- medial and lateral collateral sesamoidean ligament
14
Q
navicular bursa
A
- lies between the sesamoid bone and the digital flexor tendon
15
Q
digital cushion
A
- internal tissue deep to the frog
- lies between the ungual cartiages and is comprised of collagenous, elastic tissue infiltrated by adipose tissue
- in connection with the digital annular ligament where the deep digital flexor tendon inserts
- major shock absorber
- press blood back to heart
