Transcript Bones of the forelimb

Bones of the forelimb
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Scapula
Humerus
Radius / Ulna
Carpal bones
Metacarpal bones
Phalanges
+ sesamoid bones
usually
3 phalanges / digit
+ 2 proximal sesamoid bones / digit
+ 1 distal sesamoid bone / digit
numbering (digits, vessels, nerves): med → lat
N.B.
number of digits (1st, 2nd, 3rd, 4th and 5th)
≠ number of phalanges (1st, 2nd and 3rd)
≠ number of metacarpals (1st, 2nd, 3rd, 4th and
5th)
Forelimb
horse
Mc 3 (+ Mc 2, Mc 4)
+ 2 prox. sesam. bones
Art. metacarpophalangea, fetlock joint
Phalanx prox. (Os compedale, P1)
Art. interphalangea prox., pastern joint
Phalanx media (Os coronale, P2)
+ 1 dist. sesamoid (navicular) bone
Art. interphalangea dist., coffin joint
Phalanx dist. (Os ungulare, P3)
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Os ungulare, P3, Phalanx distalis
• Proc. palmaris lat. + med. (prox + dist.)
• Proc. extensorius
• Facies solearis, Foramen soleare
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Planum cutaneum
Linea semilunaris
Facies flexoria
• Facies parietalis
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med > lat, R/L?
Sulcus parietalis lat. + med.
• Facies articularis
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Os coronale, P2, Phalanx media
• basis: prox., caput: dist.
• Proc. extensorius (dors., prox.)
• Tuberositas flexoria (palm., prox.)
Distal sesamoid (navicular) bone
Facies flexoria + articularis
Margo prox. + dist.
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Os compedale, P1, Phalanx prox.
• basis: prox., caput: dist.
• Trigonum phalangis prox.
(palmar, tip → dist.)
2 Ossa sesamoidea prox.
Facies articularis, flexoria + interossea
tip → prox.