Hind Limb Anatomy: Joints

Question 1

Describe the hind limb joints

Answer 1

○ Sacroiliac (SI)
○ Hip joint
○ Stifle
§ 3 compartments/joints
○ Hock
§ 4 joints
○ Distal joints same
§ Metatarsophalangeal

Question 2

Describe the sacroiliac joint

Answer 2

○ Minimal movement
○ Sacroiliac ligaments
§ Reinforce joint
§ Between sacrum and ilium and ischium

Question 3

Describe a SI partial or full luxation

Answer 3

○ Common cause
§ Slipping during jump landing
○ Diagnosis
§ Palpate grating rectally
○ Prognosis
§ Dislocation heals with rest but not symmetrically
§ Injured side will be higher

Question 4

What are hunter bumps

Answer 4

○ Chronic partial SI luxation
§ Top of ilium protrudes dorsally

Question 5

Describe the hip joint

Answer 5

○ Coxofemoral articulation
§ Ball and socket joint
§ Depth of acetabulum helps stability
○ Major movement
§ Flexion and extension
§ But also…
□ Abduction
□ Adduction
□ Rotation

Question 6

Describe the hip and joint ligaments

Answer 6

○ Three ligaments maintain stability of joint
1. Ligaments maintain stability of joint
- Rupture => lateral rotation of limb (stifle out, hock in, toe out)
2. Transverse acetabular ligament
3. Accessory femoral ligament
- Unique to Equidae

Question 7

What happens during a hip joint luxation

Answer 7

○ Tuber coxae lower
○ Head of femur displaced craniodorsally

Question 8

Describe the stifle joint

Answer 8

○ Articulation
§ Femorotibial
§ Femoropatellar
○ Femur and fibula do not articulate

Question 9

Describe the femorotibial articulation

Answer 9

○ Complex joint
○ Major movement
§ Flexion and extension

Question 10

What are the components of the femorotibial

Answer 10

○ Medial and lateral compartments
§ Do not communicate
○ Medial and lateral collateral ligaments
§ Peri-articular
○ Cranial and caudal cruciate ligaments
§ Intra-articular
§ Named for tibial attachments
○ Medial and lateral menisci
§ Glide caudally when joint flexed

Question 11

Describe the femoropatellar articulation

Answer 11

○ Femoropatellar ligaments
§ Medial and lateral
§ Hold patella in trochlear groove
○ Communication with…
§ Medial femorotibial 100%
§ Lateral femorotibial 25%

Question 12

Describe the patellar ligaments

Answer 12

○ 3 patellar ligaments
§ Lateral
§ Intermediate
§ Medial
○ Infrapatellar fat pad

Question 13

Describe the patellar ligaments and stay apparatus

Answer 13

Medial and intermediate patellar ligaments form loop over medial trochlear ridge => prevents flexion of stifle => horse stands with minimal muscular effort

Question 14

Describe the tarsus

Answer 14

○ 4 articulations
§ Tibiotarsal (Tarsocrural)
§ Proximal intertarsal
§ Distal intertarsal
§ Tarsometatarsal
○ Top two joints communicate
○ Major movement
§ Flexion and extension
○ Almost all motion occurs between tibia and talus

Question 15

Describe the hock joint ligaments

Answer 15

○ Significant ligaments
§ Medial and lateral collateral ligaments
§ Long plantar ligament
- Extends from plantar calcaneus to T4 and proximal MTIV
- Mostly covered by SDFT
- Anchors calcaneus distally
® Calcaneus is pulled proximally by gastrocnemius and other tarsal extenders
- Inflammation = curb

Question 16

What is spavin?

Answer 16

○ Non-descriptive term for almost any disorder of tarsus
○ Examples
§ Bog spavin
- Tarsocrural joint distention
§ Bone spavin
- Osteoarthritis (OA) in distal two joints
§ Blood spavin
- Secondary vein distention

Question 17

Study hind limb joints on paper!