Page 1606 - Clinical Small Animal Internal Medicine

1544 Section 13 Diseases of Bone and Joint

made, surgical intervention should be considered. abrupt stop of the cranial drawer motion will suggest that
VetBooks.ir Proposed procedures include excision of the unu- the cranial cruciate ligament is intact. The final diagnosis
is based on characteristic radiographic changes on the
nited anconeal process, ulnar osteotomy, or a combi-
nation of ulnar osteotomy and lag screw fixation.
stifle joint. Lesions are located on the medial or lateral
Excision controls a major trigger for secondary OA mediolateral and especially the craniocaudal view of the
but does not stop its progression. Ulnar osteotomy is femoral condyle. Oblique views of the stifle may improve
an effective treatment of lameness, and in dogs visualization of the defect. Radiographic changes range
younger than 7–8 months of age may lead to reattach- from subchondral bone flattening and subchondral
ment of the process. These procedures are not rec- sclerosis to more severe radiolucent concave defects.
ommended for use in older dogs with UAP and Effusion is always seen and secondary arthritic changes
advanced OA; these patients should be treated for are usually present.
their OA. If the patient becomes refractory to con-
servative management, a total elbow arthroplasty Treatment
may be considered. Patients may be treated initially with restricted activity,
weight control, and NSAIDs. If the patient does not
Prognosis respond to conservative management, surgical treat-
The prognosis for FMCP and OCD depends on the ment in the form of arthrotomy or arthroscopy is indi-
extent of articular cartilage damage, the state of joint cated. The purpose of the surgical intervention is to
congruity and severity of the arthritic changes. In cases remove the cartilage flap and debride the defect, stimu-
with minimal cartilage damage and OA, the prognosis late the formation of fibrocartilage, and remove synovial
may be good. If the articular cartilage damage is more fluid cytokines and wear particles. The OC defect also
substantial, the prognosis is not as favorable and OA will may be repaired with osteochondral autografts, or resur-
progress. In these cases, the condition can be particu- faced with a single‐layer or bilayered implant. Dogs that
larly debilitating and hard to manage. The prognosis for have developed severe secondary OA unresponsive to
UAP following surgical treatment in young dogs is usu- conservative management may be treated with a total
ally good if treated before secondary changes develop. knee replacement.
However, severe OA may develop, particularly if in com-
bination with FMCP.
Prognosis
Treatment, including surgical treatment, does not
Osteochondritis Dissecans of the Stifle Joint change the progression of secondary OA. Conservatively
(Medial or Lateral Femoral Condyle) managed dogs usually end up with an intermittent lame-
ness. Surgical treatment usually improves the limb func-
Osteochondritis dissecans of the stifle joint is an uncom- tion but lameness may persist, especially after exercise.
mon form of epiphyseal OC. The lesion is located on the There is no long‐term evidence yet that the currently
weight‐bearing surface of the medial or lateral femoral used osteochondral transplant techniques improve the
condyle.
treatment outcome. The owner should be advised that
stifle OC most likely is a hereditary trait and that the
Signalment patient should not be used for breeding.
The disease is most commonly diagnosed in large‐ and
giant‐breed dogs (see Table 174.1). Males are more com-
monly affected than females. Osteochondritis Dissecans of the Hock Joint
(Medial or Lateral Trochlear Ridge of the Talus)
History and Clinical Signs
Dogs affected with stifle OCD become lame between 4 Osteochondrosis of the hock joint is an uncommon epi-
and 8 months of age, similar to other forms of joint OC. physeal OC. Lesions are localized on either the medial
Some dogs may develop lameness later in life. The lame- (most common) or lateral trochlear ridge of the talus.
ness may range from mild to severe, and tends to worsen Most patients present between 4 and 10 months of age.
with exercise.
Signalment
Diagnosis Just as with the other articular OCs, this condition is
The presumptive clinical diagnosis is based on signal- mostly seen in large‐ and giant‐breed dogs, and
ment, history, and pain on stifle hyperflexion and/or Rottweilers, retrievers, and Great Danes are most predis-
hyperextension. Joint effusion and crepitus are usually posed (see Table 174.1). Male dogs are more commonly
present. Mild cranial drawer also may be detected, but an affected than female dogs.