TOPIC 13A - ART METACARPOPHALANGEA + SUSPENSORY APPARATUS OF HORSE

Question 1

what type of joint is art metacarpophalangea (fetlock)?

Answer 1

synovial, composite, hinge

Question 2

what bones are involved in art metacarpophalangea?

Answer 2

trochlea of cannon bone
prox articular surface of P1
prox articular surface of prox sesamoid bones

Question 3

name the the two recesses of the joint capsule and where they are

Answer 3

rec dorsalis (btw cannon bone + ext tendon)
rec palmaris (btw cannon bone + suspensory lig)

Question 4

list the main groups of ligaments involved in art metacarpophalangea

Answer 4

collateral ligaments (lateral and medial)
prox sesamoid ligaments
middle sesamoid ligaments
distal sesamoid ligaments

Question 5

name the prox sesamoid ligaments

Answer 5

lig suspensorium

lig metacarpointersesmoideum

Question 6

where the lig suspensorium originate and insert?

Answer 6

from base of MC bone and branches
1st branch to prox sesmoid bone
2nd branch continues distally forming tractus appositus to m. ext. dig. communis

Question 7

name the middle sesamoid ligaments

Answer 7

lig palmaria

lig sesamoidea collaterale (medial and lateral)

Question 8

what does the lig palmaria form?

Answer 8

scutum proximale

Question 9

what is the function of scutum proximale?

Answer 9

allows smooth gliding of flexor tendons

Question 10

name the distal sesamoid ligaments

Answer 10

lig sesmoidea cruciata
lig sesmoidea rectum
lig sesmoidea obliqua
lig sesmoidea brevia

Question 11

which distal sesmoid ligament has two branches?

Answer 11

lig sesamoidea rectum (deep + supf)

Question 12

define stay apparatus

Answer 12

tendon - ligament support mechanism in the FL and HL allowing animals to carry their body weight with minimal muscular effort and energy.
Also allows horse to stand for long periods

Question 13

how does the passive stay apparatus work in the shoulder/elbow?

Answer 13

tensing SDF + DDF by dorsoflexion of fetlock in normal standing position
also contraction of triceps

Question 14

how does the this apparatus work in the carpus?

Answer 14

lacertus fibrosus prevents carpus from buckling forward

overextension prevented by accessory lig, check lig and lig on palmar surface of carpal

Question 15

how does the this apparatus work in the fetlock?

Answer 15

suspensory lig, distal sesamoid lig, palmare lig prevent hyperextension

Question 16

how does the this apparatus work in the coffin / pastern?

Answer 16

branches of suspensory lig prevent P1 + P2 buckling forward

support also from SDF + DDF tendons

Question 17

what are the 4 main elements of the passive stay apparatus?

Answer 17

lacertus fibrosus
m. interosseus medius + tractus appositus
SDF + DDF + their accessory ligaments
suspensory apparatus (fetlock)