Changes

===Phalanges===

===Phalanges===

'''Proximal Phalanx'''

'''''Proximal Phalanx'''''

The proximal phalanx proximally has two shallow articular surfaces separated by a small sagittal groove. Distally there are two convex areas separated by a sagittal groove.

The proximal phalanx proximally has two shallow articular surfaces separated by a small sagittal groove. Distally there are two convex areas separated by a sagittal groove.

'''Middle Phalanx'''

'''''Middle Phalanx'''''

The middle phalanx is half the length of the proximal phalanx, its proximal articular surface is ridged so it can articulate with proximal phalanx and the distal end resembles that of the proximal phalanx.

The middle phalanx is half the length of the proximal phalanx, its proximal articular surface is ridged so it can articulate with proximal phalanx and the distal end resembles that of the proximal phalanx.

'''Distal Phalanx'''

'''''Distal Phalanx'''''

The distal phalanx is rounded to a point distally. The proximal articular surface has two concavities separated by a ridge. The palmar border meets with the distal sesamoid bone. The dorsal aspect has a marked '''extensor process''', where the common digital extensor attaches. The solar surface has two distinct areas, the more palmar area is the roughened flexor surface and the remainder is smooth, concave and crescent-shaped. The parietal surface of the distal phalanx is that which conforms to the hoof wall. It is rough, porous and has processes on each side heading in a palmar direction. The ungual (collateral) cartilages attach to these processes, they are squarish plates which are palpable above the level of the hoof. They become more fibrous in life and may ossify.  

The distal phalanx is rounded to a point distally. The proximal articular surface has two concavities separated by a ridge. The palmar border meets with the distal sesamoid bone. The dorsal aspect has a marked '''extensor process''', where the common digital extensor attaches. The solar surface has two distinct areas, the more palmar area is the roughened flexor surface and the remainder is smooth, concave and crescent-shaped. The parietal surface of the distal phalanx is that which conforms to the hoof wall. It is rough, porous and has processes on each side heading in a palmar direction. The ungual (collateral) cartilages attach to these processes, they are squarish plates which are palpable above the level of the hoof. They become more fibrous in life and may ossify.  

'''Distal Sesamoid (Navicular) Bone'''

'''''Distal Sesamoid (Navicular) Bone'''''

The distal sesamoid in horses is known as the navicular bone. It is elongated transversely and articulates with both the distal and middle phalanx. The navicular is separated from the deep digital flexor tendon by a bursa; the flexor surface of the navicular is covered by cartilage. The proximal and distal ends are grooved and possess large foramina. The bone also has a sagittal ridge.

The distal sesamoid in horses is known as the navicular bone. It is elongated transversely and articulates with both the distal and middle phalanx. The navicular is separated from the deep digital flexor tendon by a bursa; the flexor surface of the navicular is covered by cartilage. The proximal and distal ends are grooved and possess large foramina. The bone also has a sagittal ridge.