Hindlimb Anatomy: Muscles, Tendons, and Ligaments Flashcards
What are the proximal hindlimb muscles
○ Cranial group
§ Quadriceps femoris (group of 4 muscles)
- Flex hip, extend stifle
○ Caudal group
§ Hamstring muscles
- Biceps femoris, semitendinosus, semimembranosus
- Extend hip and hock, flex or extend stifle
What are the cranial/dorsal muscles and tendons
○ Cranial tibial
○ Peroneus tertius
○ Long digital extensor
○ Lateral digital extensor
○ All flex hock, some extend digit
○ All innervated by peroneal nerve
§ Branch of sciatic nerve
Describe the cranial tibial muscle
○ Originates from proximal tibia
○ Divides into dorsal and medial tendons proximal to hock
○ Medial tendon = cunean tendon
§ Palpable on craniomedial hock
§ Landmark for distal intertarsal joint
describe the peroneus tertius
○ Originates from distal femur
○ Inserts proximal MTIII
○ Divides into dorsal and lateral tendons proximal to hock
○ Almost entirely tendon
○ Part of reciprocal apparatus
Describe the digital extensor tendons
long and lateral
§ Long called common in forelimb
§ Fuse 1/3rd way down MTIII
§ Combined tendon inserts primarily on PIII, but also on PI and PII
§ Flex hock, extend distal joints
What are the caudal/plantar muscles and tendons
○ Gastrocnemius
§ Inserts on calcaneus
○ SDFT
○ DDFT
○ Common calcaneal tendon = SDFT + gastrocnemius
○ All extend hock, some flex digit
○ All innervated by tibial nerve
§ Branch of sciatic
Describe the SDFT of the hindlimb
○ Passes over and attached to medial and lateral tuber calcanei
○ Calcaneal bursa protects
§ Buritis = capped hock
○ Inserts on PI and PII
○ No proximal check ligament
○ Extends hock, flexes fetlock and pastern
Describe the DDFT of the hind limb
○ Three parts fuse near hock
○ Lateral head passes over sustentaculum tali in tarsal canal
○ Tarsal sheath protects DDFT
§ Inflammation of tarsal sheath = thoroughpin
○ Insets on PIII
○ Extends hock, flexes distal joints
○ Absent or weak distal check
Describe the distal ligaments of the hindlimb
○ Similar to forelimb distal to hock
○ Includes
§ Suspensory ligament
§ Sesamoidean ligaments
§ Annular ligaments
Describe the hindlimb stay apparatus
○ Components
§ Patellar ligaments
§ SDFT
§ Gastrocnemius
§ Peroneus tertius
§ Long digital extensor tendon
§ DDFT with check ligament
§ Suspensory ligament and extensor branches
§ Distal sesamoidean ligaments
○ Patellar ligaments
§ Stifle joint is key joint for supporting weight in hindlimb
○ SDFT and gastrocnemius
§ From caudal femur to tuber calcanei
§ Inelastic => mechanically maintain hock in extension when stifle fixed in extension
Describe the reciprocal apparatus
○ Peroneus tertius
§ Forces hock to flex when stifle flexed
§ Simultaneous flexion allows greater clearance and minimal work
make sure to study the muscles, tendons, and ligaments of the hind limb!
