Pelvic Limb VI Flashcards
What calcaneal bursa is associated with capped hock? Cause?
Subcutaneous
trauma to the point of the hock
Subcutaneous bursa in between
skin and SDFT
Subtendinous bursa in between
SDFT and tuber calcanei
Gastrocnemius bursa in between
gastrocnemius tendon and tuber calcanei
What does the synovial sheath wrap around?
tendons passing through the tarsus to distal limb attachments
What is wrapped in the tarsal sheath?
The lateral head and caudal tibial head of the DDF pass over the sustentaculum tali through the flexor canal
Flexor canal of tarsus is passageway bound dorsally by the _________________, laterally by _______________, and plantaromedially by the ________________.
dorsally by the sustentaculum tali of the calcaneus, laterally by the calcaneus, and plantaromedially by the flexor retinaculum.
What forms the definitive DDF tendon?
The medial head of the DDF travels more medially in its own sheath and then joins the other two heads of the DDF distal to the tarsus
What does thoroughpin refer to?
excessive synovial fluid distension of the tarsal sheath
Causes of thoroughpin?
DDF tendonitis, or inflammation of the sheath (tenosynovitis) or both i.e. a tendosynovitis.
Complex medial and lateral collateral ligaments of the tarsus pass from tibial malleoli to the tarsal and metatarsal bones; function?
provide very strong medial and lateral support.
Long plantar ligament attachments?
attaches at plantarolateral calcaneus and inserts distally on T4 and MT4
Function of long plantar ligament?
helps to anchor calcaneus to tarsus, offsetting traction forces of common calcaneal tendon.
Curb refers to? Ligament associated?
refers to soft tissue swelling of plantar tarsus, often due to desmitis of the long plantar ligament.
Components of a pig digit? Weightbearing?
3 and 4; proximal, middle and distal phalanges and 2 proximal sesamoids and 1 distal sesamoid present in each digit
Components of a ruminant digit?
proximal, middle and distal phalanges and 2 proximal sesamoids and 1 distal sesamoid present in each digit.
Horse bears weight on what digit(s)? Components?
3; proximal, middle and distal phalanges and 2 proximal sesamoids and 1 distal sesamoid present for digit 3.
What species has a significant suspensory ligament?
horse
What does the suspensory ligament forms part of? Main role?
supportive fibro-osseous sling at plantar fetlock i.e. the suspensory apparatus; passive stay apparatus
Components of ruminant suspensory ligaments?
3rd and 4th interossei mm.
Where does the accessory ligament of DDF arise and insert?
Arises from plantar surface of tarsometatarsal junction (distal tarsus/proximal metatarsus) and inserts into DDFT at mid metatarsus.
Presence of Check ligament in PL?
Small or absent
Role of fibrous connection on DDFT?
acts as a break on the DDFT
Check ligament contributes to what?
passive stay apparatus
Transection of SDFT leads to?
Slight fetlock drop
Transection of SDFT and DDFT?
moderate fetlock drop and toe elevation
Transection of SDFT, DDFT and SL?
severe fetlock ‘drop’ (fetlock contacts ground) and sole of foot off ground, toe pointing proximally (to the sky!).
Role of PL passive stay apparatus?
Allows horse to bear weight on a ‘locked’ PL, with minimal muscular energy required, and meanwhile completely rest the other limb.
Four components of passive stay apparatus of PL?
- Patella locking mechanism
- Reciprocal apparatus (fibularis tertius and superficial digital flexor)
- DDFT (and its check ligament if present in pelvic limb)
- Suspensory apparatus
Requirement of joints for PSA? WHY?
Keep all joints extended to prevent their collapse without the need for significant muscular activity
Describe the reciprocal appartus?
Patella locks over stifle to keep stifle extended, this then keeps tarsus extended via the reciprocal apparatus.
The lower joints of the PSA are passively supported by?
SDFT, the DDFT and its check ligament, suspensory apparatus
