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Cattle are '''artiodactyl unguligrade''' animals. Unguligrade means that they bear their weight on a horny covering (hoof) that surrounds their distal phalanges, artiodactyl means that they bear weight on an even number of digits. They are virtually identical in their structure in the hindlimb and forelimb. The main differences are in the forelimb we have metacarpals and the metacarpophalangeal joint, the hindlimb equivalents are the metatarsals and the metatarsophalangeal joint. Also in anatomical planes we use the term palmar for forelimb and plantar for hindlimb. These terms are all interchangable in the below article depending on whether you want to talk about the fore or hindlimb.  

Cattle are '''artiodactyl unguligrade''' animals. Unguligrade means that they bear their weight on a horny covering (hoof) that surrounds their distal phalanges, artiodactyl means that they bear weight on an even number of digits. They are virtually identical in their structure in the hindlimb and forelimb. The main differences are in the forelimb we have metacarpals and the metacarpophalangeal joint, the hindlimb equivalents are the metatarsals and the metatarsophalangeal joint. Also in anatomical planes we use the term palmar for forelimb and plantar for hindlimb. These terms are all interchangable in the below article depending on whether you want to talk about the fore or hindlimb.  

==Bones==

==Bones==

====Metacarpals and Metatarsals====

====Metacarpals and Metatarsals====

* The arrangement of the metatarsals are similar to those of the metacarpals.

* The arrangement of the metatarsals are similar to those of the metacarpals.

* Metacarpal III and IV fuse in the fetus to form the large metacarpal bone. The site of fusion is marked by vascular grooves on the dorsal and palmar  surfaces of the shaft of the bone. Metacarpal V remains only as a small lateral remnant.  

* Metacarpal III and IV fuse in the fetus to form the large metacarpal bone. The site of fusion is marked by vascular grooves on the dorsal and palmar  surfaces of the shaft of the bone. Metacarpal V remains only as a small lateral remnant.  

* The distal end has two seperate articular surfaces seperated by the sagittal '''intertrochlear notch'''. The articular surfaces have two condyles seperated by a sagittal ridge.

* The distal end has two seperate articular surfaces seperated by the sagittal '''intertrochlear notch'''. The articular surfaces have two condyles seperated by a sagittal ridge.

* The dorsal aspect of the proximal end has a tuberosity for muscular attachment.  

* The dorsal aspect of the proximal end has a tuberosity for muscular attachment.  

====Phalanges====

====Phalanges====

* The proximal phalanx tends to be triangular with the interdigital surface being flattened. The proximal end is concave with a sagittal groove so it can articulate with the metacarpal bone, the palmar aspect has facets for the sesamoid bones. The distal head has two convex areas seperated by a sagittal concavity.

* The proximal phalanx tends to be triangular with the interdigital surface being flattened. The proximal end is concave with a sagittal groove so it can articulate with the metacarpal bone, the palmar aspect has facets for the sesamoid bones. The distal head has two convex areas seperated by a sagittal concavity.

* The middle phalanx is three sided and 2/3rds the length of the proximal one. The proximal end is made up of two concavities and a sagittal ridge. The distal end resembles that of the proximal phalanx.

* The middle phalanx is three sided and 2/3rds the length of the proximal one. The proximal end is made up of two concavities and a sagittal ridge. The distal end resembles that of the proximal phalanx.

==Joints==

==Joints==

====Metacarpophalangeal/Fetlock Joint====

====Metacarpophalangeal/Fetlock Joint====

* Movement - flexion and extension.  

* Movement - flexion and extension.  

* The cow has a pair of fetlock joints involving the metacarpal bone, the two proximal phalanges and two pairs of sesamoid bones. These sesamoids articulate with the proximal palmar edge of the proximal phalanges

* The cow has a pair of fetlock joints involving the metacarpal bone, the two proximal phalanges and two pairs of sesamoid bones. These sesamoids articulate with the proximal palmar edge of the proximal phalanges

====Proximal Interphalangeal/Pastern Joint====

====Proximal Interphalangeal/Pastern Joint====

* Movement - flexion and extension.

* Movement - flexion and extension.

* The joint capsule is simple and attaches by the articular margins of the two phalanges.

* The joint capsule is simple and attaches by the articular margins of the two phalanges.

====Distal Interphalangeal/Coffin Joint====

====Distal Interphalangeal/Coffin Joint====

* Movement - extension, slight flexion.  

* Movement - extension, slight flexion.  

* A distal sesamoid is closely associated with the distal phalanx, which has a navicular bursa present like in the horse.

* A distal sesamoid is closely associated with the distal phalanx, which has a navicular bursa present like in the horse.

==Musculature==

==Musculature==

'''Interosseous/Suspensory ligament'''

'''Interosseous/Suspensory ligament'''

* Function - support of the metacarpophalangeal joints.

* Function - support of the metacarpophalangeal joints.

* Origin - palmar aspect of the proximal end of the metacarpal bones, distal row of carpal bones and the joint capsule of the carpus.

* Origin - palmar aspect of the proximal end of the metacarpal bones, distal row of carpal bones and the joint capsule of the carpus.

* Insertion - At the distal third of the metacarpal bone it divides into three. The lateral branch further splits in two, attaches to the proximal sesamoids of the fetlock and then continues round dorsally on the proximal lateral phalanx and attaches to the lateral digital extensor tendon. The medial branch is likewise arranged but attaches to the medial digital extensor tendon. The middle branch dives between the groove of the distal part of the metacarpal bone and divides into two branches that attach to the tendons of the common digital extensor tendon.   

* Insertion - At the distal third of the metacarpal bone it divides into three. The lateral branch further splits in two, attaches to the proximal sesamoids of the fetlock and then continues round dorsally on the proximal lateral phalanx and attaches to the lateral digital extensor tendon. The medial branch is likewise arranged but attaches to the medial digital extensor tendon. The middle branch dives between the groove of the distal part of the metacarpal bone and divides into two branches that attach to the tendons of the common digital extensor tendon.   

====Forelimb====

====Forelimb====

'''Superficial digital flexor'''

'''Superficial digital flexor'''

* Function - flexion of the digits

* Function - flexion of the digits

* Origin - medial epicondyle of the humerus

* Origin - medial epicondyle of the humerus

* Insertion - solar surface of the middle phalanges

* Insertion - solar surface of the middle phalanges

'''Deep digital flexor'''

'''Deep digital flexor'''

* Origin - medial epicondyle of the humerus, proximal radius and ulna

* Origin - medial epicondyle of the humerus, proximal radius and ulna

* Insertion - solar surfaces of distal phalanges

* Insertion - solar surfaces of distal phalanges

'''Common digital extensor'''

'''Common digital extensor'''

* Origin - lateral epicondyle

* Origin - lateral epicondyle

* Insertion - by two branches to the middle and distal medial phalanges.

* Insertion - by two branches to the middle and distal medial phalanges.

'''Lateral digital extensor'''

'''Lateral digital extensor'''

* Origin - lateral ligament of the elbow, lateral tuberosity of the radius, ulna.

* Origin - lateral ligament of the elbow, lateral tuberosity of the radius, ulna.

* Insertion - by two branches to the middle and distal lateral phalanges.

* Insertion - by two branches to the middle and distal lateral phalanges.

====Hindlimb====

====Hindlimb====

'''Long Digital Extensor'''

'''Long Digital Extensor'''

* Origin - extensor fossa of the lateral femoral condyle.

* Origin - extensor fossa of the lateral femoral condyle.

* Insertion - It splits in two at the level of the fetlock, each branch then inserting on the extensor process of each distal phalanx.

* Insertion - It splits in two at the level of the fetlock, each branch then inserting on the extensor process of each distal phalanx.

'''Medial digital extensor'''

'''Medial digital extensor'''

* Origin - extensor fossa of the lateral femoral condyle.

* Origin - extensor fossa of the lateral femoral condyle.

* Insertion - the middle medial phalanx.

* Insertion - the middle medial phalanx.

'''Lateral Digital Extensor'''

'''Lateral Digital Extensor'''

* Origin - lateral ligament of the stifle, lateral condyle of the tibia.

* Origin - lateral ligament of the stifle, lateral condyle of the tibia.

* Insertion - on the dorsal aspect of the middle lateral phalanx.

* Insertion - on the dorsal aspect of the middle lateral phalanx.

'''Superficial Digital Flexor'''

'''Superficial Digital Flexor'''

* Origin - Supracondylar tuberosity of the femur.

* Origin - Supracondylar tuberosity of the femur.

* Insertion - solar surfaces of the middle phalanges.

* Insertion - solar surfaces of the middle phalanges.

'''Deep Digital Flexor'''

'''Deep Digital Flexor'''

==Innervation==

==Innervation==

[[Hindlimb - Anatomy & Physiology|Innervation of the Hindlimb]]

[[Hindlimb - Anatomy & Physiology|Innervation of the Hindlimb]]

==The Bovine Claw==

==The Bovine Claw==

The claws of a cow resemble a disc split in half, hence the term cloven-hoof. The split is named the '''interdigital cleft''' and gives rise to the flattened '''axial surface''', the '''abaxial surface''' is the remaining rounded surface of the claw.  

The claws of a cow resemble a disc split in half, hence the term cloven-hoof. The split is named the '''interdigital cleft''' and gives rise to the flattened '''axial surface''', the '''abaxial surface''' is the remaining rounded surface of the claw.  

The claw is divided into three regions:

The claw is divided into three regions:

* '''Sole''' - slightly concave region on the point of the sole

* '''Sole''' - slightly concave region on the point of the sole

* '''Bulb''' - slightly convex region at the heel of the sole

* '''Bulb''' - slightly convex region at the heel of the sole

* '''Wall''' - on its abaxial aspect it is convex and merges with the bulb, dorsally it reflects acutely to the convex axial wall. The junction with the bulb has a groove called the '''axial cleft'''.  

* '''Wall''' - on its abaxial aspect it is convex and merges with the bulb, dorsally it reflects acutely to the convex axial wall. The junction with the bulb has a groove called the '''axial cleft'''.  

The dermis of the wall is very similar to the horse and is arranged in laminae. This interdigitates with the epidermal horn that is produced by the papillous coronary region. The horn on the sole and bulb is also produced by papillae. The hypodermis in the bulb forms a pad of fibrous elastic tissue called the '''digital cushion'''.

The dermis of the wall is very similar to the horse and is arranged in laminae. This interdigitates with the epidermal horn that is produced by the papillous coronary region. The horn on the sole and bulb is also produced by papillae. The hypodermis in the bulb forms a pad of fibrous elastic tissue called the '''digital cushion'''.

[[Category:Musculoskeletal System]]

[[Category:Musculoskeletal System - Anatomy & Physiology]]