Difference between revisions of "Carpal and Digital Muscles - Horse Anatomy"
Jump to navigation
Jump to search
m (→Flexors) |
m (Text replace - "[[Bones and Cartilages - Horse Anatomy" to "[[Limb Bones and Cartilages - Horse Anatomy") |
||
| (4 intermediate revisions by 2 users not shown) | |||
| Line 1: | Line 1: | ||
| − | |||
==Introduction== | ==Introduction== | ||
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. | 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. | ||
| Line 5: | Line 4: | ||
=='''Extensors'''== | =='''Extensors'''== | ||
| − | The | + | The craniolateral position on the forearm, almost all originate from the lateral epicondyle of the [[Limb Bones and Cartilages - Horse Anatomy#Humerus|humerus]]. All innervated by the radial n. from the brachial plexus. |
'''''Extensor carpi radialis''''' | '''''Extensor carpi radialis''''' | ||
| Line 28: | Line 27: | ||
=='''Flexors'''== | =='''Flexors'''== | ||
| − | + | Caudal position on the forearm, originate from the caudal medial epicondyle of the [[Limb Bones and Cartilages - Horse Anatomy#Humerus|humerus]]. All innervated by the median or ulnar n. of the brachial plexus. | |
'''''Flexor carpi radialis''''' | '''''Flexor carpi radialis''''' | ||
| − | :The most medial, inserts on the proximal part of the [[Limb Bones and Cartilages - Horse Anatomy#Metacarpals and Metatarsals|second | + | :The most medial, inserts on the proximal part of the [[Limb Bones and Cartilages - Horse Anatomy#Metacarpals and Metatarsals|second metatarsal]] (medial splint)bone |
'''''Flexor carpi ulnaris''''' | '''''Flexor carpi ulnaris''''' | ||
| Line 38: | Line 37: | ||
'''''Ulnaris lateralis''''' | '''''Ulnaris lateralis''''' | ||
:The most caudolateral | :The most caudolateral | ||
| − | :'''Insertion''': [[Limb Bones and Cartilages - Horse Anatomy#Carpal Bones|accessory carpal bone]] and the [[Limb Bones and Cartilages - Horse Anatomy#Metacarpals and Metatarsals|fourth | + | :'''Insertion''': [[Limb Bones and Cartilages - Horse Anatomy#Carpal Bones|accessory carpal bone]] and the [[Limb Bones and Cartilages - Horse Anatomy#Metacarpals and Metatarsals|fourth metatarsal]] (lateral splint) bone. |
:'''Action''': Flexes the [[Joints and Ligaments - Horse Anatomy#Carpal Joint|carpus]] rather than extends it, due to its insertion caudal to the [[Joints and Ligaments - Horse Anatomy#Carpal Joint|carpal joint]] axis. | :'''Action''': Flexes the [[Joints and Ligaments - Horse Anatomy#Carpal Joint|carpus]] rather than extends it, due to its insertion caudal to the [[Joints and Ligaments - Horse Anatomy#Carpal Joint|carpal joint]] axis. | ||
| Line 51: | Line 50: | ||
:This is covered in more detail in the [[Tendons - Horse Anatomy|Equine Tendons]] section. | :This is covered in more detail in the [[Tendons - Horse Anatomy|Equine Tendons]] section. | ||
| − | + | [[Category:To Do - AP Review]] | |
| − | |||
| − | |||
| − | |||
| − | |||
| − | [[Category: | ||
Revision as of 20:00, 13 November 2012
Introduction
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
The craniolateral position on the forearm, almost all originate from the lateral epicondyle of the humerus. All innervated by the radial n. from the brachial plexus.
Extensor carpi radialis
- The most medial
- 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.
- Action: Extends and fixes the carpus, flexes the elbow
Extensor carpi obliquus (aka abductor pollicis longus)
- Origin: Cranial radius
- Insertion: Head of second metacarpal (medial splint) bone
Common Digital Extensor
- Deep to the extensor carpi radialis
- Insertion: Extensor process of the distal phalanx via the common digital extensor tendon.
- Action: Extends carpus and digit
Lateral Digital Extensor
- Caudal to the common digital extensor muscle on the lateral antebrachium
- Insertion: Dorsal proximal phalanx via the lateral digital extensor tendon.
- Action: Extends the carpus and metacarpophalangeal (fetlock) joint
Flexors
Caudal position on the forearm, originate from the caudal medial epicondyle of the humerus. All innervated by the median or ulnar n. of the brachial plexus.
Flexor carpi radialis
- The most medial, inserts on the proximal part of the second metatarsal (medial splint)bone
Flexor carpi ulnaris
- The most lateral, inserts on the accessory carpal bone.
Ulnaris lateralis
- The most caudolateral
- Insertion: accessory carpal bone and the fourth metatarsal (lateral splint) bone.
- Action: Flexes the carpus rather than extends it, due to its insertion caudal to the carpal joint axis.
Superficial Digital Flexor
- Overlies, and is partially fused with, the deep digital flexor muscle.
- Insertion: Proximal extremity of middle phalanx and the distal extremity of proximal phalanx via the superficial digital flexor tendon.
Deep Digital Flexor
- Deep to the superficial digital flexor muscle and flexor muscles of the carpus. Passes through the carpal canal before branching and continues to insert on the palmar distal phalanx via the deep digital flexor tendon.
Interosseus muscle/Suspensory ligament
- This is covered in more detail in the Equine Tendons section.