Objective—To evaluate whether body size and
anatomic site influence the quantity of bone microdamage
in dogs without osteosarcoma (OS).
Sample Population—Pairs of radii were collected
from 10 small dogs (< 15 kg) and 10 large dogs (> 25
Procedure—Specimens were stained in basic fuchsin
for bone microdamage. Transverse sections were cut
from each proximal and distal radial metaphysis at 15
and 85% of bone length. The following variables were
determined for each region: mean microcrack length
(CrLe, µm), microcrack density (CrDn,
microcracks/mm2), microcrack surface density
(CrSDn, µm/mm2), and estimated activation frequency
Results—Metaphyseal region did not significantly
influence CrDn, CrLe, and CrSDn. The CrDn and
CrSDn were influenced by body size, with microdamage
being increased in large dogs, compared with
small dogs. However, mean CrLe was not significantly
influenced by body size. Acf significantly decreased
with age and was significantly decreased in large
dogs and in the distal radial metaphysis, compared
with small dogs and the proximal radial metaphysis,
Conclusion and Clinical Relevance—Our data did
not reveal an increase in microdamage or remodeling
at the OS predilection site (ie, the distal metaphysis
of the radius), suggesting that induction of microdamage
and an associated increase in bone remodeling
are unlikely to be an important risk factor for
induction of OS. (Am J Vet Res 2002;63:896–899)
Objective—To compare postoperative discomfort
assessed by subjective pain score and plasma cortisol
concentrations in cats undergoing onychectomy that
received analgesia by use of transdermal fentanyl
(TDF) patches or an IM injection of butorphanol.
Design—Randomized prospective clinical trial.
Animals—22 client-owned cats weighing 2.2 to 5 kg
(4.84 to 11 lb) undergoing onychectomy.
Procedure—Researchers were blinded to which cats
received a TDF patch (25 µg/h) 18 to 24 hours prior to
surgery or an IM injection of butorphanol (0.2 mg/kg
[0.09 mg/lb]) at the time of sedation, immediately following
extubation, and at 4-hour intervals thereafter
for 12 hours. Clinical variables, plasma cortisol concentration,
and pain scores were evaluated and
recorded 24 hours prior to surgery, at extubation, and
2, 4, 8, 12, 24, 36, and 48 hours after surgery.
Results—The TDF group had a lower pain score than
the butorphanol group only at 8 hours after surgery.
Both groups had significantly lower mean plasma cortisol
concentrations 0, 24, 36, and 48 hours after
surgery, compared with mean plasma cortisol concentrations
prior to surgery. No significant differences
in appetite or response to handling the feet were
observed between the 2 groups.
Conclusions and Clinical Relevance—Our data did
not reveal a difference in pain relief between administration
of TDF and butorphanol. Plasma cortisol concentrations
were not different between groups.
Fentanyl appeared to provide equivalent analgesia to
butorphanol in cats undergoing onychectomy. The primary
advantage of using a TDF patch is that repeated
injections are not required. (J Am Vet Med Assoc