OBJECTIVE To assess the contribution of antirotational pins (ARPs) and an intact fibula to the compressive strength of 4 tibial plateau leveling osteotomy (TPLO) constructs (bone and implants).
SAMPLE 20 hind limbs from 10 canine cadavers.
PROCEDURES Each hind limb was assigned to 1 of 4 TPLO constructs (construct in which the ARP was removed, constructs in which 1 or 2 ARPs were left in place, and construct in which the ARP was removed and the fibula was cut). Following TPLO completion, all limbs underwent mechanical testing that included 10,000 cycles of cyclic axial compression followed by testing to failure at a displacement rate of 1 mm/s. Displacement during cyclic testing; load generated at 0.5, 1.0, and 3.0 mm of displacement; ultimate load; and failure type were recorded for each limb. Mean values were compared among the groups.
RESULTS None of the specimens failed during cyclic testing. None of the variables assessed during mechanical testing differed significantly among the 4 groups. During testing to failure, the majority (17/20) of specimens failed as the result of a long oblique fracture through the first screw hole in the distal segment.
CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that the axial compressive strength and stiffness of a TPLO construct were not significantly affected by the addition of 1 or 2 ARPs or the presence of an intact fibula. These findings appear to support removal of ARPs during uncomplicated TPLOs, but further research is warranted to assess the effect of ARP removal on bone healing and complication rates.
Objective—To evaluate use of electroacupuncture for
treatment of horses with signs of chronic thoracolumbar
Animals—15 horses with signs of chronic thoracolumbar
Procedure—Horses were randomly allocated to 1 of
3 treatment groups. Horses in group 1 received electroacupuncture
stimulation (once every 3 days for 5
treatments), those in group 2 received phenylbutazone
(2.2 mg/kg [1 mg/lb], PO, q 12 h, for 5 days), and
those in group 3 received saline (0.9% NaCl) solution
(20 mL, PO, q 12 h, for 5 days). Thoracolumbar pain
scores (TPSs) were evaluated before (baseline) and
after each treatment.
Results—Mean ± SE TPSs in horses receiving
phenylbutazone or saline solution did not change significantly
during the study. After the third treatment,
mean ± SE TPS (2.1 ± 0.6) in horses receiving electroacupuncture
stimulation was significantly lower
than baseline (6.0 ± 0.6) TPS. Mean ± SE TPSs in
horses receiving electroacupuncture stimulation
were significantly lower than baseline TPSs and TPSs
in horses receiving phenylbutazone or saline solution
after the third treatment to 14 days after the last
Conclusions and Clinical Relevance—TPSs are useful
for evaluating the efficacy of various analgesic methods
used for treatment of thoracolumbar pain in horses.
Electroacupuncture was effective for treatment of
chronic thoracolumbar pain in horses. Results provided
evidence that 3 sessions of electroacupuncture treatment
can successfully alleviate signs of thoracolumbar
pain in horses. The analgesic effect induced by electroacupuncture
can last at least 2 weeks. Phenylbutazone
administered PO did not effectively alleviate signs
of thoracolumbar pain in horses in this study. (J Am Vet Med Assoc 2005;227:281–286)
OBJECTIVE To evaluate mechanical properties of pigeon (Columba livia) cadaver intact humeri versus ostectomized humeri stabilized with a locking or nonlocking plate.
SAMPLE 30 humeri from pigeon cadavers.
PROCEDURES Specimens were allocated into 3 groups and tested in bending and torsion. Results for intact pigeon humeri were compared with results for ostectomized humeri repaired with a titanium 1.6-mm screw locking plate or a stainless steel 1.5-mm dynamic compression plate; the ostectomized humeri mimicked a fracture in a thin cortical bone. Locking plates were secured with locking screws (2 bicortical and 4 monocortical), and nonlocking plates were secured with bicortical nonlocking screws. Constructs were cyclically tested nondestructively in 4-point bending and then tested to failure in bending. A second set of constructs were cyclically tested non-destructively and then to failure in torsion. Stiffness, strength, and strain energy of each construct were compared.
RESULTS Intact specimens were stiffer and stronger than the repair groups for all testing methods, except for nonlocking constructs, which were significantly stiffer than intact specimens under cyclic bending. Intact bones had significantly higher strain energies than locking plates in both bending and torsion. Locking and nonlocking plates were of equal strength and strain energy, but not stiffness, in bending and were of equal strength, stiffness, and strain energy in torsion.
CONCLUSIONS AND CLINICAL RELEVANCE Results for this study suggested that increased torsional strength may be needed before bone plate repair can be considered as the sole fixation method for avian species.
Objective—To evaluate effects of maropitant, acepromazine, and electroacupuncture on morphine-related signs of nausea and vomiting in dogs and assess sedative effects of the treatments.
Design—Randomized controlled clinical trial.
Procedures—Dogs received 1 of 6 treatments: injection of saline (0.9% NaCl) solution, maropitant citrate, or acepromazine maleate or electroacupuncture treatment at 1 acupoint, 5 acupoints, or a sham acupoint. Morphine was administered after 20 minutes of electroacupuncture treatment or 20 minutes after injectable treatment. Vomiting and retching events and signs of nausea and sedation were recorded.
Results—Incidence of vomiting and retching was significantly lower in the maropitant (14/37 [37.8%]) group than in the saline solution (28/37 [75.7%]) and sham-acupoint electroacupuncture (32/37 [86.5%]) groups. The number of vomiting and retching events in the maropitant (21), acepromazine (38), 1-acupoint (35), and 5-acupoint (34) groups was significantly lower than in the saline solution (88) and sham-acupoint electroacupuncture (109) groups. Incidence of signs of nausea was significantly lower in the acepromazine group (3/37 [8.1%]) than in the sham-acupoint group (15/37 [40.5%]). Mean nausea scores for the saline solution, maropitant, and sham-acupoint electroacupuncture groups increased significantly after morphine administration, whereas those for the acepromazine, 1-acupoint electroacupuncture, and 5-acupoint electroacupuncture groups did not. Mean sedation scores after morphine administration were significantly higher in dogs that received acepromazine than in dogs that received saline solution, maropitant, and sham-acupoint electroacupuncture treatment.
Conclusions and Clinical Relevance—Maropitant treatment was associated with a lower incidence of vomiting and retching, compared with control treatments, and acepromazine and electroacupuncture appeared to prevent an increase in severity of nausea following morphine administration in dogs.
Objective—To assess relationships of acetabular volume (AV), femoral head volume (FV), and portion of the femoral head within in the acetabulum (FVIA) with each other and with degrees of hip joint laxity and degenerative joint disease from youth to maturity in dogs predisposed to developing hip joint osteoarthritis (OA).
Animals—46 mixed-breed half- or full-sibling hound-type dogs.
Procedures—The distraction index (DI), AV, FV, FVIA, and degree of osteoarthritis (OA score) were quantified in 1 hip joint at 16, 32, and 104 weeks of age. Relationships among variables were evaluated within and between ages. Ratios corresponding to OA scores were compared within ages. Differences among 16-week ratios corresponding to 32-week OA scores and among 16- and 32-week ratios corresponding to 104-week OA scores were evaluated.
Results—Significant positive relationships existed between FV and AV across ages as well as between FVIA/FV and FVIA/AV and between DI and OA score across and within most ages. Such relationships also existed within these variables across most ages. Negative relationships of DI and OA scores with FVIA/FV and FVIA/AV within and among all ages were significant. Sixteen-week AVs, FVs, and FVIAs were greater and FV/AVs and OA scores were less than 32- and 104-week values. The 32-week FVIA/FV was less than 16- and 104-week values, and the 32-week FVIA/AV was less than the 104-week value. The FVIA/FV and FVIA/AV were lower and the DI was higher with higher OA scores within and among most ages.
Conclusions and Clinical Relevance—Structural volumes in lax canine hip joints changed predictably relative to each other during growth, despite degenerative changes. Measures developed in this study may augment current diagnosis and treatment strategies for hip dysplasia in dogs.
Objective—To evaluate the reliability of a method for
inducing colic via small intestinal distention in horses
and to examine the analgesic potential of bilateral
electroacupuncture (EAP) at the Guan-yuan-shu (similar
to BL-21) acupoint.
Animals—5 healthy adult horses, each with a gastric
Procedure—A polyester balloon connected to an electronic
barostat was introduced into the duodenum via
the gastric cannula. At 2 specified intervals (before and
after commencement of EAP), the balloon was inflated
to a barostat-controlled pressure that induced signs of
moderate colic. Each inflation was maintained for 10
minutes. Heart and respiratory rates were continuously
recorded. Frequency of various clinical signs of colic was
recorded by 2 trained observers during various combinations
of balloon inflation and EAP. Each horse received
each of 5 treatment protocols (EAP at 20 Hz, sham EAP
at 20 Hz, EAP at 80 : 120 Hz dense:disperse, sham EAP
at 80 : 120 Hz dense:disperse, no treatment). Sham EAP
was at a point located 2 cm lateral to the Guan-yuan-shu
Results—Duodenal distention consistently induced a
significant increase in frequency of signs of colic.
None of the EAP protocols caused a significant reduction
in frequency of these clinical signs during distention.
Conclusions and Clinical Relevance—The method
described is reproducible and highly controllable
method for inducing colic that involved duodenal distention
that should be useful in evaluating the efficacy
of various analgesic strategies. Bilateral EAP at the
Guan-yuan-shu acupoint was ineffective in reducing
signs of discomfort induced by this method. (Am J Vet