Forelimb Anatomy: Tendons and Ligaments Flashcards
What are the forelimb tendons?
common digital extensor tendon
lateral digital extensor tendon
superficial digital flexor tendon (SDFT)
deep digital flexor tendon (DDFT)
Describe the common digital extensor tendon
cranial/dorsal
insertion - proximal PIII
extends carpal, fetlock, pastern, and coffin joints
major extensor tendon of limb
damaged –> not lame, learns to flick limb forward
Describe the lateral digital extensor tendone
insertion - proximal PI
extends carpus and fetlock joint
does not unite with CDET
Describe the superficial digital flexor tendon
caudal/palmar
branches distal to fetlock
insertion - distal PI and proximal PII
extends elbow, flexes carpus, fetlock and pastern joints
most commonly injured tendon
oval or flattened cross section
Describe the deep digital flexor tendon
caudal/palmar
insertion - PIII
superficial to suspensory ligament and deep to SDFT (distal to carpus)
flex carpus and distal joints
round cross section
What are the four ligaments
suspensory
check
annular
sesamoidean
describe the suspensory ligament
○ AKA interosseous ligament
○ Located on palmar surface of MCIII between MCII and MCIV
○ Originates from distal carpal bones and proximal MCII
○ Attaches to proximal sesamoids
○ Extensor branched continue distally and dorsally from sesamoids to attach to extensor tendon
Describe the check ligaments
○ Provide palmar carpal stability during motion
○ Superior/Proximal/Radial
§ From distal caudomedial radius to merge with SDFT
○ Inferior/Distal/Carpal or Sub-carpal
§ From palmar carpal ligament to merge with DDFT
Describe the annular ligaments
○ Hold flexor tendons in place
○ Thickenings of deep fascia
○ Palmar annular ligament
§ Palmar to fetlock
○ Proximal digital annular ligament
§ Forms X, palmar to PI
○ Distal to digital annular ligament
§ Palmar to PII and PIII
describe the proximal sesamoidean ligaments
○ Intersesamoidean ligament
§ Connects medial and lateral proximal sesamoids
§ Extends dorsally to form articular surface
○ Collateral sesamoidean ligaments
§ From abaxial surfaces to distal MCII and proximal PI
○ Distal sesamoidean ligaments
§ Short, cruciate, oblique, and straight
§ Insert on PI and PII
Describe the distal sesamoidean ligaments
○ Collateral suspensory ligaments to PI and PII
○ Distal (impar) ligament to PIII
describe the passive stay apparatus of forelimb
○ Enables horse to stand for long periods with minimal muscular effort
§ “sleep” standing up
§ Perpetual readiness to run from danger
○ Tendons and ligaments stabilize joints
§ In position suitable for support of body
§ Often means preventing them from flexing
□ Exceptions
® Pastern (extended)
® Fetlock (overextended)
Make sure to also study tendons and ligaments on paper
