Page 658 - Adams and Stashak's Lameness in Horses, 7th Edition

624 Chapter 5

majority occurred from a kick to the medial aspect of Diagnosis
52
the bone (Figure 5.26). Age may play a role in fracture The presence of a displaced radial fracture is con-
VetBooks.ir tures are usually noted in older horses (older than 2 firmed on radiographic examination. Several views are
configuration; comminuted or butterfly fragment frac-
often needed to evaluate the configuration and extent of
years), whereas simple oblique fractures occurred in
younger horses. Transverse fractures were exclusive to the fracture. Computerized tomography (CT) may be
foals less than 6 months of age (Figure 5.27). 72 useful to help determine the ideal internal repair method
if a complex comminuted fracture is to be assessed
completely.
Clinical Signs Acute nondisplaced fractures may be difficult to diag-
Horses with complete displaced fractures present nose initially on radiographic exam. If a nondisplaced
with a non‐weight‐bearing lameness, varying degrees of fracture is suspected, the horse should be cross‐tied in a
swelling in the antebrachium, and instability associated stall to prevent it from lying down, and repeat radiographs
with the fracture site. Crepitation may be felt and pain should be taken in 2–4 days. This time period usually
elicited when the distal limb is manipulated. Wounds allows recognition of the fracture lines. Alternatively,
and penetration of the skin from the fracture on the dis- nuclear scintigraphy can be used to assist in the
tal medial side of the antebrachium are common. diagnosis.
Horses that present with complete or incomplete Stress fractures are usually best diagnosed by nuclear
nondisplaced fractures are usually very lame but are scintigraphy where a focal increased uptake of the radi-
willing to bear some weight on the limb. Instability and onuclide in the midshaft of the radius is usually found
52
crepitation are not present; however, there is usually (Figure 5.28). Confirmation with radiography can be
some swelling of the antebrachium, and pressure applied performed at a later date. Evidence of focal endosteal or
to the region is often painful. Wounds at the site of periosteal reaction indicates a healing stress fracture
7
traumatic impact are often present on the medial distal that will correlate with the focal area of increased
aspect of the antebrachium (Figure 5.26). uptake. Alternatively, quantitative scintigraphy can be
85
Stress fractures are difficult to identify on physical performed. This enables the clinician to assess the
signs alone. Horses generally present with a history of degree of injury if there are no initial radiographic findings
an acute onset of lameness that subsides with rest and as well as later during the convalescent period when the
reoccurs with exercise. Horses are often mildly lame at quantitative findings can be used to accurately deter-
examination and shoulder flexion may worsen the lame- mine a date to return to training or work.
ness. These fractures can also occur bilaterally. 52

Figure 5.26. Wound on the medial aspect of the antebrachium
from a kick injury. This horse had a concurrent distal radial fracture.
Radiographs of the radius should always be taken in horses with Figure 5.27. A transverse complete midshaft fracture of the
these injuries. radius of a foal. Source: Courtesy of Dr. Martin Waselau.