equine radiographic anatomy
DESCRIPTION
lecture slidesTRANSCRIPT
Equine Radiographic Anatomy
Views of the hoof Lateromedial Dorsopalmar
Lateral radiograph of the equine foot
P1
P2
P3
Anatomy: • First phalanx • Second phalanx • Third phalanx • Navicular bone • Proximal interphalangeal joint •Distal interphalangeal joint Navicular bone
Proximal interphalangeal joint AKA pastern joint
Distal interphalangeal joint AKA coffin joint
Distal limb anatomy
• Extensor process of P3
• Common digital extensor
• Deep digital Flexor
• Straight sesmoidean ligament
• Insertion of oblique sesmoidean ligament
• Impar ligament
• Digital cushion
Articular surface Proximal
surface
Flexor surface
Distal surface
Lateral radiograph of the equine foot
5
Views of the hoof • Dorsal proximal to palmar distal
( Upright pedal )
• Good view to asses solar margin of P3 and the navicular bone
Dorsal proximal to palmar distal
•Navicular bone •Coffin bone/P3 •Vascular channels • Solar margin • Semilunar canal • Wings of the coffin bone
Dirt in the white line on bottom of hoof
Vascular channels
Crena margins solearis
8
Crena margins solearis - a smooth rounded concavity of the distal phalanx solar margin (more prominent in hindlimb)
Views of the hoof
• Palmar proximal to palmar distal ( Skyline )
• Good view to asses flexor surface and medullary cavity of the navicular bone
Palmar proximal to palmar distal (skyline)
•Navicular bone •Flexor surface •Medullary cavity • Wings of coffin bone
Dorsoproximolateral to palmarodistomedial-
To throw out the lateral wing of P3.
Equine Metacarpal-phalangeal joint Fetlock
Lateral Dorsal palmar DLPMO
• Proximal sesamoids • Lateral condyle of MC3
• Ergot • Sagittal ridge
MC3
P1
MC4 Prox. Sesamoids
Flexed lateral
The only way to know medial versus lateral and which limb is radiographed is if the film was correctly labeled at the time the image was obtained.
The views
• Radiographs are named by the direction through which the photons transverse the patient.
Lateral Medial
Dorsal
Palmar
• Dorsopalmar radiograph of the carpus
Dorsopalmar view equine carpus
Lat. Styloid process
Radius
Radial CB
Inter-mediate CB Ulnar CB
Third CB 4th CB
2nd CB
MC3 MC4
Dorsal view of the carpal bones
MC2
R I U
A
2 3 4
MC2 MC3 MC4
The views
Lateral Medial
Dorsal
Palmar
• Lateromedial
• Radiographs are the most sensitive on the edges
Flexed views
• Manipulation of the limb to better image anatomic structures of interest.
• Visualization of articular surfaces
Lateral views of the equine carpus
Flexed lateral radiograph of the carpus
Anatomy: • Radial carpal bone • Intermediate carpal bone • Ulnar carpal bone • C3 • C4
* Need to know how to differentiate between radial and intermediate carpal bones and C3 versus C4. So if there is a chip fracture, you can tell the surgeon which bone is fractured.
Three main joints: • Radial carpal •Middle carpal •Carpal metacarpal
Dorsolateral to palmaromedial
Lateral
Dorsal
Medial
Palmar
• Palmar-lateral structures such as the lateral splint bone are easily seen in this view.
Dorsolateral to palmaromedial radiograph of the equine carpus
Palmar lateral su
rface D
ors
al m
edia
l su
rfac
e
C4
MC4
Accessory carpal bone curled around and well projected. Articulates with ulnar carpal bone.
R
C3
On the lateral surface, the fourth carpal bone is not aligned with MC4
Dorsomedial to palmarolateral
L Medial
Dorsal
Palmar
• There is summation of structures in the middle,
such as the lateral splint bone.
Dorsomedial to palmarolateral radiograph of the equine carpus
Do
rsal
late
ral s
urf
ace
Palm
ar med
ial surface
C2
MC2
Medially the second carpal bone stacks up nicely on top of MC2.
Accessory carpal bone is poorly visualized.
DMPLO Equine Carpus
C1
• The first carpal bone is sometimes present and the fifth carpal bone is rarely present. They are non-articular, will vary in size, have smooth margins and may be present on one side only.
C2
MC2
Sky line views
Lateral to medial radiograph of the equine tarsus
Anatomy:
1. Tibia
2. Calcaneous
3. Chestnut
4. Tarsocrural joint
5. Proximal intertarsal joint
6. Distal intertarsal joint
7. Tarsometatarsal joint
8. Metatarsal 3
1
3
2
4
5
6
7
8
Dorsoplantar view of the equine tarsus
TIBIA
MT3
TB3 Central TB
Medial malleolus
Lateral malleolus
TB 4
Lateral trochlear ridge of the talus
Medial trochlear
ridge of the talus
DIRT
MT3
DIRT Medial malleolus
Lateral malleolus
Medial
trochlear
ridge of
the talus
Dorsal view of the tarsus
TB 4
TB3
4 2
Central TB
DLPMO
• Calcaneous
• Distal intermediate ridge of the tibia
• MT4 – Lateral splint bone
• MT2 – Medial splint bone
• Fourth tarsal bone
• Medial mallelous
• Lateral trochlear ridge of the talus
• Sustentaculum tali
• T1 and T2 fused
• Dorsolateral surface of the tarsometatarsal joint
Dorsomedial to palmar lateral radiograph of the tarsus
Hook Medial trochlear ridge of the femur
Lateral trochlear ridge of the femur
Patella
Femoral condyles
Tibial condyles
Tibial tuberosity
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Lateromedial view equine stifle
The medial trochlear ridge is larger than the lateral trochlear ridge.
Extensor fossa of femur
Extensor groove of tibia
Caudal to cranial radiograph of the equine stifle
Anatomy:
• Medial condyle
• Lateral condyle
• Medial intercondylar eminence
• Fibula
• Medial tibial condyle
The fibula can have multiple separate centers of ossification. Do not mistake these as fractures.
“In the barn terminology”
• Knee carpus
• Cannon bone MC3
• Splint bones MC2 and MC4 in horses
• Fetlock metacarpal phalangeal joint
• Pastern joint Proximal interphalangeal joint
• Coffin joint Distal interphalangeal joint
• Coffin bone Distal phalanx