Lecture 3: Equine Pelvic Limb (Exam 1) Flashcards
What is the difference btw/ the thoracic limb & the pelvic limb
The pelvic limb has a true bony connection to the trunk
How does the pelvis articulate w/ the trunk & the pelvic limb
- Pelvis to the trunk: sacroiliac joint
- Pelvis to the pelvic limb: coxal joint
What joins the left & right os coxae art the ventral midline
Pelvic symphysis
What are the three bones of the os coxae (plus the 4th developmentally)
- Ilium
- Ischium
- Pubis
- Acetabular bone(developmentally)
What is the croup
Region btw/ the hip bone & tail dock
What is the point of the hip
Tuber coxae
What is the point of the buttock
Ischiatic tuberosity
Label the following:
Label the blue, red, & green areas
- Red: Tuber sacrale (sacral tuber)
- Blue: Tuber coxae (coxal tuber)
- Green: Tuber ischii (Ischial tuber or ischiatic tuberosity)
Which pelvis belongs to a canine and which belongs to equine
- A: Dog
- D: Equine
What parts of the pelvis are palpable
- Tuber sacrale
- Tuber coxae
- Tube ischii
- Greater trochanter
Label 1 - 4
Where is the greater trochanter
2/3 of the distance btw/ the tuber coxae & the tuber ischii
What is the slope of the pelvis used for & what can happen if its to steep or flat
- Used for conformation
- Sign of lameness
Label the following:
Whats the difference btw the canine sacrotuberous ligament & equine
In canines the sacrotuberous ligament is cord like while in equine it is very broad and considered the sacrosciatic ligament
What are the attachments of the sacrosciatic ligament
- Ischiatic spine
- Transverse process of the sacrum
What foramina are associated with the sacrostatic ligament
Greater & lesser sciatic foramina
What is a difference btw/ the greater & lesser sciatic foramina
The greater has vessels & nerves running through/around it while the lesser sciatic only
What is the ventral border (pecten pubis or pubic brim”
The cranial most rim of the pelvis located btw/ the dorsal pubic tubercle & the iliopubic eminence
What is the lateral border (arcuate line)
The ridge extending btw/ the iliopubic eminence & the auriculat surface of the ilium
Where is the tuberosity for the insertion of the psoas minor muscle found
Midway along the lateral border of the pelvic inlet
What does the dorsal border consist of
- Sacral promontory
- Wing of the sacrum
Label the blue, green, & yellow line
- Yellow: ventral border
- Green: Lateral border
- Blue: Dorsal border
Label the following:
What are the bones of the pelvic limb in Equine
- Femur
- Patella
- Tibia/Fibula
- Tarsal bones
- Metatarsal bones
- Proximal sesamoids
- Phalanges
What is a major structure @ the metatarsal joints
Proximal sesamoids
What is the difference btw/ the greater trochanter in canines and Equine
- In equine the greater trochanter is divided into a cranial & caudal part
- Rember the cranial part sits lower than the caudal part
What is affiliated w/ the cranial part
A subtendinous bursa (trochanteric bursa)
Describe the trochanteric bursa
A tendon that is deep to the gluteal muscle tendon
What is different about the third trochanter in equine, & why
- It is larger
- B/c the superficial gluteal m is larger
Describe the trochlea in Equine
- Comprised of a medial & lateral ridge w/ a deep depression (trochlear groove) btw/ them
- the medial trochlear ridge is larger & has a pronounced tubercle
What is a resting & gliding surface
- Resting: where the patella is sitting while resting (is more proximal)
- Gliding: where the patella lays when it is moving
Where does the long digital extensor originate from and pass through
- Originates: the extensor fossa of the femur
- Passes through: Extensor groove of the tibia
What is this
Extensor groove of the tibia
Along with the long digital extensor muscle what other muscle originates from the extensor fossa in equine
Peroneus (fibularis) tertius
What is this
Extensor fossa
What is the origin of the superficial digital flexor muscle
The supracondylar fossa
What is this, describe it, and what muscle originates from it
- Lateral supracondylar tuberosity
- roughened cranial border of the supracondylar fossa
- Origin of the lateral head of the gastrocnemius m
Is there a medial supracondylar tuberosity
Yes it is just not that prominent
What is the difference between the fibula found in equine vs. canine
- In canine the bone is separate from the tibia & elongated
- In horses the distal extremity of the fibula is reduced & does not extend the full lenght of the crus
What characteristics should you look for to not get the fibula confused w/ the splint bones
- the fibula does not have buttons
- the dorsal part of the fibula is more flat
What is shown on the cranial view & distal view (what does this articulate w/)
- Cranial view: the lateral malleolus of the tibia
- Distal view: the cochlea which is associated w/ the trochlea
What is different in the metatarsal bones of equine
metatarsul one & two are fused together
Label the following
What is this process & what inserts here
- Process: calcanean tuber
- Some tendon (?)
Label the following:
What is the weight-bearing digit in the pelvic limb
The 3 digit only
Describe the tarsus in equine
- the gused tarsal bones (1 & 2) articulate w/ MT 2 & 3
- Tarsal bone 3 articulates w/ MT 3
- Tarsal bone 4 articulates w/ MT 3 & 4
Decribe the metatarsus in equine
Consist of MT 3 (the cannon bone) & MT 2 & 4 (the medial & lateral splint bones)
Describe the digits in equine
- Proximal phalanx (p1 or long pastern)
- Middle phalanx (p2 or short pastern)
- Distal phalanx (p3 or coffin)
Where are the sesamoid bones located in the equine pes
- A pair is found proximal @ the metatarsophalangeal joint
- One is found @ the distal interphalangeal jt
Label the yellow, green, & purple areas
- yellow: Tarsus
- Green: Metatarsus
- Purple: Digit
What are the black arrows pointing to?
The proximal & distal sesamoid bones
Label these palpable landmarks
What is the sacroiliac joint
The articulation btw/ the auricular surface of the wing of the sacrum & the auricular surface of the ilium
What happens if there is excessive strain on the sacroiliac joint
Can lead to ligament tears & dislocatoion of the SI joint (“Hunter’s Bump”)
Name this joint and the articulations that create it
- Black arrow: The coxal joint
- Yellow area: acetabulum of the os coxa
- Articulation of the femoral head w/ the acetabulum of the os coxa
Describe the acetabulum in equine
- A deep depression that receives the head of the femur to form the coxal joint
- Coposed of the ilium, ischium, pubis, & acetabular bone (not distinguishable in adults)
What is the labrum
Fibrocartilage that extends the rim & deepens the acetabulum as the horse ages
Label the purple area and the yellow star
- Purple: articular surface of the acetabulum
- yellow star: acetabular notch
What spans the acetabulum notch
- Spans during life by the transverse acetabular lig
T/F: the acetabular fossa is a articular surface
F it is non-articular
What is the attachment site of the ligament of the femoral head
the acetabular fossa
Describe the two femoral ligaments in equine
- Allows for high level of stability & secures against luxation
- both ligaments pass deep to the transverse acetabular ligament & insert on the fovea capitis of the head of the femur
What is this & why is it so big
- Fovea capitis of the femur
- To allow the attachment of 2 ligaments
Describe the Accessory ligament
- unique to equine
- Detaches from the prepubic tendon
- restricts movement & stabilizes the joint b/c of forward pull on the prepubic tendon by the weight of the abdominal viscera
What is the location of the coxal joint
About 2/3 the distance btw/ the tuber coxae & tuber ischii, slightly cranioventral to the caudal part of the greater trochanter
T/F: The stifle joint in equine is similar to the one found in canines
True
What type of joint is the stifle joint
Compound joint
List the articulations found in the stifle joint
- Femorotibial articulation
- Femoropatellar articulation
- Proximal tibiofibular articulation
Bony articular surfaces are (congruent/incongruent) & (stable/unstable), why are they?
- Incongruent
- Unstable
- B/c of rounded femoral condyles & flat tibial condyles
What is required for congruency & stability
Accessory structures
Label the following:
What ligament is not found in equine (or large animals in general)
Transverse ligament btw/ the lateral & medial side
What is the difference btw/ the equine patellar ligaments & canine
There are multiple patellar ligaments in equine
Label the following
- 1 = medial patellar ligaments
- 2 = Intermediate or middle patellar ligament
- 3 = lateral patellar ligament
What attaches the patella to the tibial tuberosity in equine
The 3 patellar ligaments
What is the blue stars referring to, and why is it important
- Parapatellar fibrocartilage btw/ the medial patellar ligament & patella
- important for patellar locking mechanism
What ligaments form a loop areound the medial trochlear ridge of the femur
- Medial patellar
- Intermediate patellar
- patella fibrocartilage
- parapatellar fibrocartilage
Label the following and what do they help do
- A = medial patellar ligament
- B = Intermediate patellar ligament
- C = Patella & parapatellar fibrocartilage
- D = Medial trochlear ridge of the femur
- aid in the “locking” of the patella on the resting surface of the tubercle of the medial trochlear ridge of the femur
What are the two synovial compartments of the femorotibial joint
- medial
- Lateral
Label the blue, green, & pink areas
- Green = medial synovial compartment
- Lateral synovial compartment
- Femoropatellar joint
T/F: the femoropatellar joint has a smal divided synovial compartment
False it has a large undivided synovial compartment
Which synovial compartments usually communicate
The femoropatellar & medial femorotibial
Which synovial compartments sometimes communicate (25%)
Femoropatellar & lateral femorotibial compartments
Which synovial compartments do not communicate
The medial femorotibial & lateral femorotibial
Describe the patellar fat pad
- A large fat pad located btw/ the joint capsule of the femoropatellar joint & the patellar ligaments
- Bulges cranially btw/ the patellar ligaments
What can be palpated in the stifle joint
- tibila tuberosity (1)
- patellar ligaments (2)
- Patella (3)
- locate the tibial tuberosity proximocranial to the bulge of crural muscles & work proximally
List the tarsal joints
- Tibotarsal (tarsocrural) joint
- Proximal intertarsal joint
- Distal intertarsal joint
- Tarsometatarsal joint
Label the following:
- A = tibotarsal (tarsocrural) joint
- B = Proximal intertarsal jont
- C = Distal intertarsal joint
- D = Tarsometatarsal joint
Describe the tibotarsal (tarsocrural) joint
- Btw/ the tibia & talus
- Greatest degree of movement
Describe the procimal intertarsal joint
- btw/ the talus, calcaneus, & central & 4th tarsal bones
- little to no movement
Describe the distal intertarsal joint
- Btw/ the central, fused 1st/2nd, & 3rd tarsal bones
- little to no movement
Describe the tarsometatarsal joint
- Btw/ the tarsus & metatarsus
- little to no movement
Tarsal joints have a __________________ ______ fibrous joint capsule w/ the ____ membrane attached around the articular margins of each component joint
- Common outer
- synovial
What tarsal joints communicate freely
The tarsocrural & proximal intertarsal joint
Which tarsal joints rarely communicate
The proximal intertarsal & distal intertarsal joint
Which tarsal joints communicate ~40% of the time
The distal intertarsal & tarsometatarsal joint
What does “communication” mean when talking about joints
They share fluid or allow fluid to cross over btw/ joints
List the components of the suspensory apparatus found in the metatarsophalangeal (fetlock) joint
- proxiaml sesamoid bones
- intersesamoidean ligament (scutum)
- 3 distal sesamoidean ligaments
Describe the distal interphalangeal (coffin) joint
- located w/in the hoof capsule (“coffin”)
- Includes the distal sesamoid (navicular) bone
what digit joint is known as the pastern joint
The proximal interphalangeal joint
Label the following:
- A = metatarsophalangeal (fetlock) joint
- B = Proximal interphalangeal (pastern) joint
- C = distal interphalangean (coffin) joint
