Page 133 - Adams and Stashak's Lameness in Horses, 7th Edition

Examination for Lameness 99

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Figure 2.60. Distal limb flexion test in which the interphalangeal (pastern and coffin) and fetlock joints are flexed simultaneously.

The entire length of each small metacarpal/metatarsal
bone (splint bone) should be palpated for heat, pain, and
swelling with the limb weighted and unweighted. With the
limb elevated, the palmar/plantar and axial surfaces of the
splint bones can be palpated by pushing the suspensory
ligament and tendons toward the opposite side (Figure 2.62).
The splint bone can be palpated with the thumb applying
pressure as needed. Heat, pain, and swelling may indicate a
fracture or a condition referred to as “splints” if located in
the proximal aspect of MCII. Splint fractures most com­
monly involve the medial splint bone in the forelimb and
the lateral splint bone of the hindlimb. It is not uncommon
to palpate nonpainful enlargements of the splint bone,
which are often incidental findings. However, some middle
and proximal splint bone fractures heal with excessive cal­
lus that may contribute to lameness.

SUSPENSORY LIGAMENT
The suspensory ligament (interosseous medius mus­
cle) lies just palmar/plantar to the splint bones in the
metacarpal/metatarsal groove. It should be palpated
with the limb weight‐bearing and with the limb flexed.
Deep palpation is often needed to identify swelling and
pain, and comparison between the lateral and medial
2,6
branches may be helpful. Damage to the suspensory
tends to occur distally within the branches of the sus­
pensory ligament or at its proximal attachment to the
MC/MT. However, secondary suspensory desmitis may
be associated with a healing splint fracture anywhere
Figure 2.61. Palpation over the dorsal middle third of the along its length. The proximal attachment of the suspen­
metacarpus to identify heat, pain, and swelling associated with sory ligament to the MC/MT can be palpated by push­
dorsal metacarpal disease. ing the flexor tendons to the side and applying pressure