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====Muscles of the Carpal and Digital Joints====
 
====Muscles of the Carpal and Digital Joints====
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The horse, as well as other domestic mammals, have a limited range of motion in the carpal joints compared with humans; therefore these muscles act as either extensors or flexors.
    
====='''Extensors'''=====
 
====='''Extensors'''=====
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'''''Extensor carpi radialis'''''
 
'''''Extensor carpi radialis'''''
:The most medial, inserts on the metacarpal tuberosity.
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:The most medial
 
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::'''Insertion''': Metacarpal tuberosity of the proximal third metacarpal (cannon) bone. Uniquely in the horse, the lacertus fibrosus (detachment of the ''biceps brachii'') joins this muscle prior to its insertion.
'''''Ulnaris lateralis'''''
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::'''Action''': Extends and fixes the carpus, flexes the elbow
:The most lateral, inserts on the accessory carpal bone.
      
'''''Extensor carpi obliquus''''' (aka '''''abductor pollicis longus''''')
 
'''''Extensor carpi obliquus''''' (aka '''''abductor pollicis longus''''')
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'''''Flexor carpi ulnaris'''''  
 
'''''Flexor carpi ulnaris'''''  
 
:The most lateral, inserts on the accessory carpal bone.
 
:The most lateral, inserts on the accessory carpal bone.
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'''''Ulnaris lateralis'''''
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:The most caudolateral
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:'''Insertion''': Accessory carpal bone and the fourth metacarpal (lateral splint) bone.
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:'''Action''': Flexes the carpus rather than extends it due to its insertion caudal to the carpal joint axis.
    
'''''Superficial Digital Flexor'''''
 
'''''Superficial Digital Flexor'''''
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