Small Animal Radiology and Ultrasound: A Diagnostic Atlas and Text

Chapter Four The Appendicular Skeleton 493
Fig. 4-23 A 7-month-old male Miniature Poodle was dropped by an
owner at 2 months of age and experienced pain for 2 weeks following the
injury. The dog was lame and the right elbow was painful on palpation.
There is subluxation of the radial humeral articulation with a large gap
between the radial head and the distal humeral condyle. The coronoid
process of the ulna is irregular and there is sclerosis of the subchondral
bone of the ulna. The humeral ulnar articulation is widened (arrow).
The cranial cortex of the radius and the ulna are thickened. There is a
slight bowing deformity of the radius. The proximal radial and distal
ulnar growth plates remain open, but the distal radial growth plate
appears to be closed. Diagnosis: Premature closure of the distal radial
physis. The resultant lack of radial growth has produced the elbow subluxation
with remodeling and secondary degenerative joint disease.
Fig. 4-24 A 6-month-old female
Basset Hound was injured at 4
months of age. The injury was mild
and was not treated at that time. The
right foreleg became deviated laterally.
There is subluxation of the humeral
ulnar articulation (open arrow). The
radius and ulna are curved. The proximal
and distal radial growth plates
remain open. The distal ulnar growth
plate is closed except for a small remnant
that remains open on the caudal
and lateral aspects (closed arrows).
Diagnosis: Premature closure of the
distal ulnar physis. This has resulted in
growth deformity, with the upward
pressure of the radius on the distal
humerus causing the elbow subluxation.
If this continues, fracture of the
anconeal process could result.
Although some degree of limb curvature
is considered normal in a dog
of this breed, the changes noted here
were more severe than in the opposite
limb.