A18

Question 1

The Pastern joint

Answer 1

articulationes interphalangeae proximales manus

Saddle joint with flexion and extension and allows for some movement from side to side

Between the caput if the proximal phalanx with the fovea articularis of the middle phalanx - more saddle shaped in Ru and Eq

Question 2

Joint capsule of the pastern joint

Answer 2

Has a dorsal and a plantar recessus

In the equine:

• the dorsal recess lies under the common extensor tendon
• the palamar recess will extend proximally

In Carnivores:

• the joint capsule is closely related to both the extensor and flexor tendons
• dorsal wall is thickened by cartilage
• sesamoid cartilages are almost within the joint capsule

Ruminant

• no communication between the recesses
• a lot of synovia

Question 3

Ligaments of the pastern joint

Answer 3

Ligg. collateralia

Ligg. plantaris

Question 4

Ligg. collateralis of pastern joint

Answer 4

Eq:

• oblique, between tuberositas extensoria on 1st phalanx to the tuberosity on the 2nd

Ru

• axial and abaxial
• axial common collateral ligament

Ca

• only ligament present in the ca
• fossa on first phalanges to the epicondyle of the second
• 1st digit (if present) attaches distally to the proximal end of the distal phalanx

Pigs

• depression on the first phalanx to the protuberance on the second
• stronger in the chief digits

Question 5

Lig. plantaris of the pastern joint

Answer 5

present in the horse, the chief digit of ruminants and pigs

Equine:

• axial and abaxial
• from the ridges of the plantar surface and the middle border to the tuberositas flexoria

Ru:

• lies in the middle of the axial and the abaxial ligaments

Pigs

• lateral, medial and palmar aspect of each digit
• plantar surface of the 1 st phalanx to the sexond phalanges below the joint margin
• axial and abaxial

Question 6

Coffin joint

Answer 6

Articulationes interphalangeae distales manus

Termed the claw joint in all but the horse

Eq:

• distal end of the second phalanx + the proximal end of the third phalanx + navicular bone
• extension and flexion
• can rotate to some extent, to adjust to irregular surfaces when walking

Question 7

Joint capsule of the coffin joint

Answer 7

recessus dorsalis and plantaris + some small additional recesses

Question 8

Ligaments of the coffin joint

Answer 8

1. Ligg. collateralia
2. Ligg. sesamoidea collateralia
3. Ligg. chondrocompedalia
4. ligg. chondrosesamoidea
5. ligg. chondroungularia collateralia
6. Ligg. chondrounglaria cruciata

Question 9

ligg. sesamoidea collateralisa

Answer 9

Eq, bo

elastic suspensory ligament of the navicular bone

dorsal to the collateral ligament of the pastern joint to the axial surface of the hoof cartilage to the navicular bone ( sometimes it continous to the third phalanx)

Question 10

ligg. chondrocempedalia

Answer 10

elastic

goes from the first phalanx, above and behind the collateral ligaments of the pastern joint

the lateral fibers will go to the proximal border of the axial surface of the cartilage

medial fibers goes to the distal phalanx

Question 11

Ligg. chondrocoronalia

Answer 11

proximally on the dorsal border of the hoof cartilage + collateral ligament of the coffin joint to the second phalanx

Question 12

Ligg. chondrosesamoidea

Answer 12

between axial surface of the cartilage and the side of the navicular bone

Question 13

ligg. chondroungularia collateralia

Answer 13

distal border of cartilage + angle of the coffin bone

Question 14

ligg. chondroungularia cruciata

Answer 14

covered by the deep flexor tendon

axial surface of the cartilage to the distal phalanx of opposite side

Question 15

Case of ruminant and su regarding the claw joint

Answer 15

lig. interdigitale proximale and distale

Question 16

Digital flexors of hindlimb

Answer 16

M. flexor digiroum superficialis

M. flexor digitorum profundus

Question 17

M. flexor digitorum superficialis

Answer 17

lies between the two heads of the gastrocnemius muscle

proximal to tuber calcanei the tendon passes from deep to superficial position to form galea calcanea before it continous down to the digit(s)

in horses the crural part of this muscle is important part of the passive stay apparatus and fixation

O: tuberositas supracondylare laterales

I: tuber calcanei, and middle phalanx of the chief digits

A: flexes the chief digits and extends the hock

Question 18

M. flexor digitorum profundus

Answer 18

Three individual muscles

1. flexor hallucis longus - fibua, tibia and the interosseus membrane
2. tibialis caudalis - from fibula
3. flexor digitalis longus - from tibia (caudoproximally)

Their tendons unite to fomr the deep digital flexor tendon

Eq, Ru, Su: flexor hallucis longus is applied directly to the caudal surface of the tibia

In the carnivores the caudal tibial is not a part of the deep digital flexor.

the tendon descends in sulcus sustentaculum tali and is held in place by flexor retinaculum

Question 19

Digital extensors of the hindlimb

Answer 19

extensor digitorum longus

extensor digitorum lateralis

extensor digiti 1 longus

Question 20

M. extensor digitorum longus

Answer 20

passes thorugh sulcus extensoria and lies on recessus subextensorius, passage over the bursa which is formed by the lateral and medial protrusions of the lateral diverticulum of the joint capsule - becomes a strong tendon at the level of the proximal transverse ligament

O: fossa extensoria

I: 2-5th digit on the distal phalanx

A: extends the digits and draws foot forwards

Question 21

M. extensor digitorum lateralis

Answer 21

O: fibula

I: first phalanx of digit ( ru 2nd phalanx of IV)

A: extends and abducts digit V

Question 22

M. extensor hallucis longus

Answer 22

only in Su and Ca

in Eq + ru it is fused with cranial tibial

O: fibula and interosseus membrnae

I: Mt 2 and 2nd digit

A: extends the second digit and the first if present