Page 116 - Equine Clinical Medicine, Surgery and Reproduction, 2nd Edition

Musculoskeletal system: 1.3 The foot 91

VetBooks.ir the sensitive structures, application of hoof testers 1.159
should localise the pain. The nail should be removed
and, if present, any subsequent abscessation treated
appropriately.

Shoe selection
Poor shoe choice may also predispose to lame-
ness. A shoe that is too large, either too wide or
too long, is more likely to be pulled off, while a
shoe that is too small or short is likely to result
in pressure at the heels or angle of the sole and
predispose to bruising, hoof cracks and underrun
heels. A shoe with a web that is too wide will cause
pressure on the sole if the sole is dropped, while
a shoe with a web that is too narrow will not pro-
tect the adjacent sole. A shoe that is too heavy will
cause fatigue, which will in turn predispose the
horse to injury. Fig. 1.159 This shoe has been placed asymmetrically,
leading to foot imbalance and an abnormal landing
Shoe placement position. (Photo courtesy Graham Munroe)
Placement of the shoe should normally be sym-
metrical about the axis of the frog. When shoe
placement is asymmetrical, so that the shoe is 1.160
placed further laterally than medially, greater
stress will be placed on the lateral wall, and vice
versa (Fig. 1.159). If a shoe is unintentionally
rotated, one heel will have greater coverage than
the other. The heel with less coverage will be
prone to the same problems as if the shoe were
too short.

Inappropriate use of traction
Traction devices such as toe grabs or calks are widely Fig. 1.160 Racing plate with toe grab and heel
used to increase a horse’s speed or prevent a horse stickers.
from slipping (Fig. 1.160). Such devices concen-
trate stress in the adjacent wall. Additionally, trac-
tion devices that elevate one side of the limb more FRACTURES OF THE DISTAL PHALANX
than the other, or elevate the toe or heel, will induce
an imbalance in the limb if the horse is standing Definition/overview
on a firm surface. Traction devices that prevent a Fractures of the distal phalanx occur in several con-
planted foot from rotating as a horse turns place figurations: fractures of the body and wings of the
undue torque on a limb and predispose the distal distal phalanx; fractures of the extensor process; and
limb to phalangeal fractures. Consequently, it is best fractures of the solar margin (Figs. 1.161–1.163).
to use removable traction devices, use them only Fractures of the body/wings of the distal phalanx
when deemed necessary and use the lowest, broadest are subdivided into articular and non-articular frac-
devices possible. tures. A classification into seven different types has