Objective—To test the hypotheses that the densities
of macrophages in the synovial membranes and capsules
of stifle joints in dogs with ruptured cranial cruciate
ligaments are greater than those of normal joints
and that those densities in affected joints are positively
correlated with the chronicity and severity of
Animals—17 dogs with naturally occurring rupture of
the cranial cruciate ligament and 5 healthy control
Procedure—All dogs underwent orthopedic and radiographic
evaluations. In affected dogs, duration of clinical
signs was used as an indicator of disease chronicity
and the severity of osteoarthritis in the stifle joint
was determined radiographically. Joint capsule specimens
were evaluated histologically; macrophages,
interleukin-6, and tumor necrosis factor-α were identified
by use of immunocytochemical techniques.
Results—Compared with unaffected joints,
macrophage density was increased in all affected
joints. Duration of disease was significantly associated
with radiographic severity of osteoarthritis and
synovial macrophage density. Synovial macrophage
density was significantly associated with severity of
osteoarthritis and with the presence of interleukin-6
and tumor necrosis factor-α.
Conclusions and Clinical Relevance—Results suggest
that synovial macrophages may be involved in the
development of pathologic changes (including osteophyte
formation) in the stifle joints of dogs with
osteoarthritis secondary to rupture of the cranial cruciate
ligament. Determination of the importance of synovial
macrophages in the development of changes in
osteoarthritic joints may result in new treatment strategies
that involve elimination of the deleterious effects
of those cells. (Am J Vet Res 2005;66:493–499)
Objective—To investigate the effects of disk fenestration and ventral slot formation on vertebral motion unit (VMU) range of motion (ROM) and determine the effects of fenestration and ventral slot width on VMU ROM.
Sample Population—C5-C6 VMUs from 10 skeletally mature canine cadavers.
Procedures—Specimens were assigned to 2 groups (5 specimens/group). Surgery was performed in which width of a fenestration and a ventral slot was 33% (group 1) or 50% (group 2) the width of the vertebral body. Flexion-extension, lateral bending, and axial torsion ROMs were measured during loading before surgery, after fenestration, and after ventral slot formation. Range of motion was compared within groups to determine effects of surgical procedure on stability and between groups to determine effects of width of fenestration and ventral slot on stability.
Results—For both groups, fenestration resulted in a significant increase in ROM during flexion-extension, compared with results for intact specimens. Ventral slot formation resulted in a significant increase in ROM during flexion-extension and lateral bending, compared with results for intact specimens. Ventral slot formation resulted in a significant increase in ROM only during flexion-extension, compared with results for fenestrated specimens. There were no significant differences in ROM of the intact, fenestrated, and ventral slot specimens between groups.
Conclusions and Clinical Relevance—Analysis of these results suggests that fenestration and ventral slot procedures each affect the biomechanics of the C5-C6 VMU. Width of a fenestration or ventral slot up to 50% of the width of C5-C6 may be clinically acceptable.
Objective—To determine clinical, radiographic, and
histologic abnormalities in adult cats > 1 year old with
spontaneous (ie, nontraumatic) femoral capital physeal
Procedure—Medical records of cats > 1 year old with
femoral capital physeal fractures and no history of
trauma were examined.
Results—Mean ± SD age of the cats was 22.5 ± 6.5
months. Twenty-five cats were neutered males. Mean
weight of the cats was significantly greater than mean
weight of a group of age- and sex-matched control cats.
Of 16 cats for which age at the time of neutering was
known, 14 had been neutered before 6 months of age.
Nine cats had bilateral fractures. Severity of femoral
neck osteolysis and sclerosis increased with increased
duration of clinical signs. The contralateral femoral capital
physis, distal femoral physes, and proximal tibial
physes were radiographically open in 13 of 18, 19 of 24,
and 24 of 24 cats, respectively. Histologically, the epiphysis
contained normal articular cartilage and bone,
but attached growth plate cartilage lacked the normal
columnar arrangement of chondrocytes.
Conclusions and Clinical Relevance—Results suggested
that adult cats with spontaneous femoral
capital physeal fractures were most likely to be
heavier, neutered males with delayed physeal closure.
(J Am Vet Med Assoc 2002;221:1731–1736)