Changes

The vascular supply to the digit in the pelvic limb is largely the same as in the thoracic limb.

The vascular supply to the digit in the pelvic limb is largely the same as in the thoracic limb.

The caudal branches of the '''saphenous artery and medial saphenous vein''' continue as the '''lateral and medial plantar vessels''', running with the deep digital flexor tendon, over the sustentaculum tali, to the level of the metatarsus. The vein lies superficial to the corresponding artery.  In the digit, the medial and lateral digital veins, arteries and nerves lie next to each other in a dorsal to plantar arrangement; this can be remembered as VAN (vein, artery, nerve).  

The caudal branches of the '''saphenous artery and medial saphenous vein''' continue as the '''lateral and medial plantar vessels''', running with the [[Tendons - Horse Anatomy#Flexors|deep digital flexor tendon]], over the sustentaculum tali, to the level of the [[Bones and Cartilages - Horse Anatomy#Metacarpals and Metatarsals|metatarsus]]. The vein lies superficial to the corresponding artery.  In the digit, the medial and lateral digital veins, arteries and nerves lie next to each other in a dorsal to plantar arrangement; this can be remembered as VAN (vein, artery, nerve).  

The '''medial and lateral plantar vessels''' enter the metatarsus to give rise to the '''deep plantar arterial and venous arches'''; from which the '''medial and lateral metatarsal vessels''' originate. The medial and lateral metatarsal arteries join the '''medial and lateral digital arteries''', which result from the bifurcation of the '''dorsal metatarsal artery''', close to the fetlock.  The dorsal metatarsal artery continues as the '''short dorsal pedal artery''', which subsequently forms the '''cranial tibial artery''' on the dorsal hock.  The cranial tibial, dorsal pedal and dorsal metatarsal arteries supply the digit and hoof.

The '''medial and lateral plantar vessels''' enter the metatarsus to give rise to the '''deep plantar arterial and venous arches'''; from which the '''medial and lateral metatarsal vessels''' originate. The medial and lateral metatarsal arteries join the '''medial and lateral digital arteries''', which result from the bifurcation of the '''dorsal metatarsal artery''', close to the [[Joints and Ligaments - Horse Anatomy#Metacarpophalangeal (Fetlock) Joint|fetlock]].  The dorsal metatarsal artery continues as the '''short dorsal pedal artery''', which subsequently forms the '''cranial tibial artery''' on the dorsal [[Joints and Ligaments - Horse Anatomy#Tarsal Joint|hock]].  The cranial tibial, dorsal pedal and dorsal metatarsal arteries supply the digit and [[Hoof - Horse Anatomy|hock]].

The '''dorsal common digital vein''' crosses the medial surface and the '''dorsal metatarsal artery''' crosses the lateral surface of the third metatarsus (cannon bone) obliquely. The dorsal common digital vein joins the medial plantar vein in the distal third of the cannon bone.  The '''medial plantar vein''' then becomes the '''medial digital vein''' at the level of the metacarpophalangeal (fetlock) joint. At this level, the medial plantar vein anastamoses with the '''lateral plantar vein''' via the '''distal deep plantar arch'''.

The '''dorsal common digital vein''' crosses the medial surface and the '''dorsal metatarsal artery''' crosses the lateral surface of the [[Bones and Cartilages - Horse Anatomy#Metacarpals and Metatarsals|third metatarsal]] (cannon bone) obliquely. The '''dorsal common digital vein''' joins the '''medial plantar''' vein in the distal third of the [[Bones and Cartilages - Horse Anatomy#Metacarpals and Metatarsals|cannon bone]].  The '''medial plantar vein''' then becomes the '''medial digital vein''' at the level of the [[Joints and Ligaments - Horse Anatomy#Metacarpophalangeal (Fetlock) Joint|metacarpophalangeal]] (fetlock) joint. At this level, the medial plantar vein anastamoses with the '''lateral plantar vein''' via the '''distal deep plantar arch'''.

The '''medial and lateral digital arteries''' run on their corresponding sides of the digit, forming '''dorsal and plantar branches''' to the proximal and middle phalanx. These branches anastamose with each other to form '''arterial circles''' around the proximal and middle phalanges.

The '''medial and lateral digital arteries''' run on their corresponding sides of the digit, forming '''dorsal and plantar branches''' to the [[Phalanges - Horse Anatomy#Proximal Phalanx|proximal phalanx]] and [[Phalanges - Horse Anatomy#Middle Phalanx|middle phalanx]]. These branches anastamose with each other to form '''arterial circles''' around the [[Phalanges - Horse Anatomy#Proximal Phalanx|proximal]] and [[Phalanges - Horse Anatomy#Middle Phalanx|middle]] phalanges.

The '''dorsal branch of the lateral and medial digital arteries''' arises at the level of the distal phalanx. It runs though the foramen/notch in the plantar process of the distal phalanx into the parietal groove.  The digital arteries continue to the solar surface and enter the solar foraminae on either side to anastamose within the bone, forming the '''terminal arch'''.  Branches of the terminal arch run in osseous canals to the parietal surface, where they supply the laminar dermis. Some branches also emerge close to the solar margin and anastamose to form an artery that follows this margin.

The '''dorsal branch of the lateral and medial digital arteries''' arises at the level of the [[Phalanges - Horse Anatomy#Distal Phalanx|distal phalanx]]. It runs though the foramen/notch in the plantar process of the [[Phalanges - Horse Anatomy#Distal Phalanx|distal phalanx]] into the parietal groove.  The digital arteries continue to the solar surface and enter the solar foraminae on either side to anastamose within the bone, forming the '''terminal arch'''.  Branches of the terminal arch run in osseous canals to the parietal surface, where they supply the laminar dermis. Some branches also emerge close to the solar margin and anastamose to form an artery that follows this margin.

'''Digital veins''' are satellite to the arteries down to and into the distal phalanx, but not all the branching arteries are accompanied by veins.  There is a dense '''venous plexus''' in the coronary and laminar dermis of the sole which drains into the '''medial and lateral digital veins''' via many smaller veins.  Most of these veins lie subcutaneously, just proximal to the hoof, others run directly to the digital veins from the axial surface of the ungual cartilages.

'''Digital veins''' are satellite to the arteries down to and into the [[Phalanges - Horse Anatomy#Distal Phalanx|distal phalanx]], but not all the branching arteries are accompanied by veins.  There is a dense '''venous plexus''' in the coronary and laminar dermis of the sole which drains into the '''medial and lateral digital veins''' via many smaller veins.  Most of these veins lie subcutaneously, just proximal to the [[Hoof - Horse Anatomy|hoof]], others run directly to the digital veins from the axial surface of the [[Hoof - Horse Anatomy#Ungual Cartilages|ungual cartilages]].

==References==

==References==