Normal Radiographic Anatomy of the Equine metacarpus/metatarsus, fetlock, and distal extremity
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Transcript of Normal Radiographic Anatomy of the Equine metacarpus/metatarsus, fetlock, and distal extremity
Normal Radiographic Anatomy of the Equine
metacarpus/metatarsus, fetlock,
and distal extremity
Dr Virginie De Busscher
First Year Radiology
Metacarpus(MC)/Metatarsus(MT)Metacarpus(MC)/Metatarsus(MT)
• MC and MT are similarMC and MT are similar
• Large nutrient foramen in MC/MT IIILarge nutrient foramen in MC/MT III
• “ “splint bones”: 2splint bones”: 2ndnd and 4 and 4thth MC/MT MC/MT
• Dorsopalmar(plantar) view: mDorsopalmar(plantar) view: marker placed laterally arker placed laterally
• Lateral views: marker is dorsalLateral views: marker is dorsal
4 views4 views
Multiple oblique views if fracture suspectedMultiple oblique views if fracture suspected
Dorsopalmar(plantar) viewDorsopalmar(plantar) view
Metacarpus/Metatarsus
A: Second MC/MTB: Fourth MC/MTC: Third MC/MT
D: Medial proximal sesamoid bone
E: Lateral proximal sesamoid bone
1: Nutrient foramen2: MC/MT phalangeal joint
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From KSUCVM
From Ulg (Belgium)
Lateromedial viewLateromedial view
Metacarpus/Metatarsus
A: Second MC/MTB: Fourth MC/MTC: Third MC/MT
D: Medial proximal sesamoid bone
E: Lateral proximal sesamoid bone
1: Nutrient foramen2: MC/MT phalangeal joint
DLPM oblique viewDLPM oblique view
Metacarpus/Metatarsus
Dorsal
Palmar/Pl
MedialLateral
DLPMo = DorsoLateral-PalmaroMedial oblique
B: Fourth MC/MTC: Third MC/MTD: Medial proximal sesamoid boneE: Lateral proximal sesamoid bone
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DMPL oblique viewDMPL oblique view
Metacarpus/Metatarsus
DMPLo = Dorsomedial-PalmaroLateral oblique
Dorsal
Palmar/Pl
MedialLateral
A: Second MC/MTC: Third MC/MTD: Medial proximal sesamoid boneE: Lateral proximal sesamoid bone
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FetlockFetlock
Metacarpophalangeal/Metatarsophalangeal Articulation
• Dorsopalmar(plantar) views: Dorsopalmar(plantar) views:
impossible to distinguish med/lat without marker impossible to distinguish med/lat without marker
Marker has to be lateralMarker has to be lateral
• Lateral views: marker is dorsalLateral views: marker is dorsal
• Few differences between forelimb and hindlimbFew differences between forelimb and hindlimb
4 views + lateromedial view in flexion if needed4 views + lateromedial view in flexion if needed
Lateromedial viewLateromedial view
Metacarpophalangeal/Metatarsophalangeal Articulation
A: Third MC/MT boneB: Proximal phalanx (P1)
1: Sagittal ridge3: Palmar process of proximal phalanx4: Condyles of third metacarpal bone5: Proximal sesamoid bone
Dorsopalmar(plantar) viewDorsopalmar(plantar) view
Metacarpophalangeal/Metatarsophalangeal Articulation
A: Third MC/MT boneB: Proximal phalanx (P1)C: Medial proximal sesamoid boneD: Lateral proximal sesamoid boneE: Metacarpo(tarso)-phalangeal jointF: Middle phalanx (P2)G: Third phalanx (P3)H: Proximal interphalangeal joint I: Distal interphalangeal joint
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Dorsopalmar(plantar) viewDorsopalmar(plantar) view
Metacarpophalangeal/Metatarsophalangeal Articulation
To prevent superimposition of the proximal sesamoid bones over the joint, the beam should be descending Dorsoproximal-Palmarodistal oblique view
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Dorsopalmar(plantar) viewDorsopalmar(plantar) view
Metacarpophalangeal/Metatarsophalangeal Articulation
A: Third MC/MT boneB: Proximal phalanxC: Medial proximal sesamoid boneD: Lateral proximal sesamoid boneE: Metacarpo(tarso)-phalangeal jointJ: Depression for medial collateral ligament attachment1: Sagittal ridge
Sagittal ridge at MC/MT distal aspect
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Metacarpophalangeal/Metatarsophalangeal Articulation: Dorsopalmar view
MC/MT distal aspect
P1 dorsal
P2 dorsal P2 palmar/plantar
P1 proximal P1 palmar/plantar
R
DLPM oblique viewDLPM oblique view
Metacarpophalangeal/Metatarsophalangeal Articulation
A: Third MC/MT boneB: Proximal phalanxC: Medial proximal sesamoid boneD: Lateral proximal sesamoid boneE: Metacarpo(tarso)-phalangeal joint1: Sagittal ridge3: Palmar process of proximal phalanx/Lateral palmar tubercle (eminence)6: Medial condyle of third MC/MT bone
DLPMo
Dorsal
Palmar/Pl
MedialLateral
Beam can be slightly descending (proximo-distal)
R
DMPL oblique viewDMPL oblique view
Metacarpophalangeal/Metatarsophalangeal Articulation
A: Third MC/MT boneB: Proximal phalanxC: Medial proximal sesamoid boneD: Lateral proximal sesamoid boneE: Metacarpo(tarso)-phalangeal joint1: Sagittal ridge2: Lateral condyle of third metacarpal/tarsal bone3: Palmar process of proximal phalanx
Dorsal
Palmar/Pl
MedialLateral
DMPLo
R
Forelimb HindlimbForelimb Hindlimb
Metacarpophalangeal/Metatarsophalangeal Articulation
DP view - Forelimb DP view - Hindlimb
• The proximal sesamoid bones are higher
Bulging
• The MT is convex at its distal aspect
• The proximal sesamoid bones are more triangular
FootFoot
Distal Extremity
•No shoe, trimmed, placed on a blockNo shoe, trimmed, placed on a block
• For the DP views: Soap or “play-doh” (soft tissue opacity) toFor the DP views: Soap or “play-doh” (soft tissue opacity) to fill the 3 sulci of the frog fill the 3 sulci of the frog avoid artifact due to air avoid artifact due to air
• Marker placed Marker placed laterallylaterally (impossible to tell if med or lat (impossible to tell if med or lat without marker)without marker)
• Use of a Use of a gridgrid
• 4 views4 views
Lateromedial viewLateromedial view
Distal Extremity
A: Middle phalanxB: Third phalanxC: Navicular bone1: Proximal interphalangeal joint2: Distal interphalangeal joint3: Extensor process4: Dorsal surface5: Palmar process
From Animalia curandi
Lateromedial viewLateromedial view
Distal Extremity
A: Middle phalanxB: Third phalanxC: Navicular bone1: Proximal interphalangeal joint2: Distal interphalangeaol joint3: Extensor process4: Dorsal surface5: Palmar process
Navicular bone
Distal Extremity
Proximal margin of the navicular boneFlexor surfaceProximal palmar process
Distal palmar process
Dorsal recess of thedistal interphalangeal joint
Extensor process
Articular margin Solar canal
Distal margin of the navicular bone
Lateromedial viewLateromedial view
Dorsoproximal-palmar(pl)odistal oblique view
Distal Extremity
A: Middle phalanxB: Third phalanxC: Navicular bone1: Proximal interphalangeal joint2: Distal interphalangeaol joint3: Extensor process4: Dorsal surface5: Palmar process6: Vascular channel7: Solar margin
6
55
2
7
B
Dorsoproximal-palmar(plantar)odistal oblique view
R
Dorsopalmar(plantar) viewDorsopalmar(plantar) view
Distal Extremity
Dorsopalmar(plantar) view
A: Middle phalanxB: Distal phalanxC: Navicular bone6: Proximal interphalangeal joint7: Distal interphalangeal jointA
B
C
6
7
R
Extensor processExtensor process
Distal Extremity
R
The extensor process can have different shapes
Palmar processesPalmar processes
Distal Extremity
Proximal
Distal
L
L
Navicular bone = distal sesamoid boneNavicular bone = distal sesamoid bone
Distal Extremity
A: Middle phalanxB: Distal phalanxC: Navicular bone1: Flexor cortex 2: Proximal border3: Articular surface4: Distal border5: Ridge to which impar ligament attaches
Navicular boneNavicular bone
Distal Extremity
C: Navicular bone1: Flexor cortex2: Proximal border7: Distal interphalangeal joint 7a: Palmar aspect 7b: Dorsal aspect
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Navicular boneNavicular bone
Distal Extremity
Proximal and distal margins
Extensor process
Articular margins
Articular surface of third phalanx
Vascular channels
Crena marginis solearis
Toe notch = Crena marginis solearisToe notch = Crena marginis solearis
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Navicular boneNavicular bone
Distal Extremity
Palmaro(plantar)oproximal-palmar(plantar)odistal oblique view
C: Navicular bone3: Articular surface8: Palmar aspect of middle phalanx9: Nutrient foramen10: Sagittal ridge11: Articulation between navicular bone and middle phalanx
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DLPM oblique viewDLPM oblique view
Distal Extremity
DLPMo
Dorsal
Palmar/Pl
MedialLateral
RR
DMPL oblique viewDMPL oblique view
Distal Extremity
Dorsal
Palmar/Pl
MedialLateral
DMPLo
R
R
Hoof wallHoof wall
Distal Extremity
A: Middle phalanxB: Third phalanxC: Navicular bone
B
A C
BC