Page 127 - Adams and Stashak's Lameness in Horses, 7th Edition

Examination for Lameness 93

PALPATION AND MANIPULATION

VetBooks.ir Gary M. Baxter and ted S. StaShak

Palpation of the musculoskeletal system is a very
2
important aspect of any lameness evaluation. With prac­
tice and experience, subtle abnormalities can be detected
that are often indicative of the site of the problem.
Thorough palpation of the patient is often performed
prior to observing it at exercise, but this is often patient
and clinician dependent. Most manipulative tests are per­
formed after exercise. A systematic approach of palpa­
tion is recommended to avoid missing abnormalities.
One approach is to palpate the forelimb proximally to
distally in a weight‐bearing position and then distally to
proximally with the limb picked up or unweighted (Video
2.1). Palpation of the hindlimbs can be performed in the
2
same manner, paying close attention to the medial aspects
of the stifle and tarsus (Video 2.2). The back and axial
skeleton are usually palpated last because some horses
become agitated with manipulation of the back (Video
2.3). Hoof tester examination of the feet is usually per­
formed after the entire musculoskeletal system has been
palpated. The following discussion briefly describes tech­ Figure 2.43. Bilaterally symmetrical hoof wall rings that were not
niques to visually examine, palpate, and manipulate the associated with lameness or any other known problem within the
different anatomic regions of the equine musculoskeletal hoof wall.
system to ensure a complete examination.

FOOT
The size and shape of the foot on the lame limb should
be compared to its opposite member. The examiner is
looking for asymmetry in foot size, abnormal hoof wear,
ring formation and heel bulb contraction, shearing of the
heels and quarters, hoof wall cracks, swellings that are
primarily associated with the coronet, and foot imbal­
ances. 15,17 Asymmetry in foot size may be a result of
trauma, lack of weight‐bearing leading to contraction,
and congenital or developmental defects. In general, the
limb with the smallest foot is usually the lame limb.
Hoof wall ring formation can be unilateral (trauma) or Figure 2.44. View of both front feet in a horse with forelimb
bilateral and is not always associated with lameness lameness. The front feet of the same horse as viewed from the side
(Figure 2.43). Heel contraction often results from are illustrated in Figure 2.45. The medial wall of the right foot is
decreased weight‐bearing of the affected limb and is usu­ concave with the coronary band pushed proximally suggesting
ally a symptom rather than the cause of the lameness excessive concussion. In addition the heels are contracted and
(Figures 2.44 and 2.45). Visual examination of heel bulb overgrown.
contraction is best performed with the examiner stand­
ing or squatting near the flank and looking at both right in chronic cases. The sole should be slightly concave.
and left heel bulbs at once (Figure 2.44). Asymmetry in Some horses are flat‐footed and therefore predisposed to
heel bulb height (sheared heels) is most frequently asso­ sole bruising. Convexity of the sole dorsal to the apex of
ciated with improper trimming and shoeing. Foot imbal­ the frog (“dropped soles” in front of the frog) is consid­
ances can either be dorsopalmar/plantar (DP), lateral/ ered abnormal and is often associated with rotation of the
medial (LM), or a combination of the two (Figures 2.44 distal phalanx. In some cases, the offending cause of lame­
and 2.45). These imbalances often alter the shape of the ness may be identified immediately, such as a nail wedged
hoof wall and can result in abnormal stresses applied to in the frog (Figure 2.47). However, the clefts of the frog
the foot and other support structures. may need to be opened with a knife to properly evaluate
After superficial cleaning of the sole, abnormal wear the depths of the sulci for evidence of thrush or canker.
on the shoe and/or sole, collapsed heels, heel bulb con­ The hoof wall should be checked for cracks that may
traction, and frog atrophy should be noted (Figure 2.46). extend into the sensitive laminae (they are most com­
Secondary frog atrophy may accompany heel contraction mon in the toe and quarter), uneven wear, and excessive