Objective—To evaluate a 3-D kinematic model of the hind limb developed by use of a joint coordinate system in dogs.
Animals—6 clinically normal adult mixed-breed dogs.
Procedures—17 retroreflective markers were affixed to the skin on the right hind limb of each dog. Eight infrared cameras were arranged around a gait platform to record marker locations as dogs were recorded moving through the calibrated space 5 times during a walk and trot at velocities of 0.9 to 1.2 m/s and 1.7 to 2.1 m/s, respectively. Local and global coordinate systems were established, and a segmental rigid-body model of the canine hind limb was produced. Dynamic 3-D joint kinematic measurements were collected for the hip, stifle, and tarsal joints.
Results—Sagittal (flexion-extension), transverse (internal-external rotation), and frontal (abduction-adduction) plane kinematic measurements were acquired during each trial for the hip, stifle, and tarsal joints.
Conclusions and Clinical Relevance—The joint coordinate system allowed acquisition of 3-D kinematic measurements of the hip, stifle, and tarsal joints of the canine hind limb. Methods were described to model 3-D joint motion of the canine hind limb. (Am J Vet Res 2010;71:1118-1122)
Objective—To compare results of single-point kinetic gait analysis (peak and impulse) with those of complete gait waveform analysis.
Animals—15 healthy adult mixed-breed dogs.
Procedures—Dogs were trotted across 2 force platforms (velocity, 1.7 to 2.1 m/s; acceleration and deceleration, 0.5 m/s2). Five valid trials were recorded on each testing day. Testing days 1 and 2 were separated by 1 week, as were days 3 and 4. Testing days 1 and 2 were separated from days 3 and 4 by 1 year. A paired t test was performed to evaluate interday and interyear differences for vertical and craniocaudal propulsion peak forces and impulses. Vertical and craniocaudal propulsion force-time waveforms were similarly compared by use of generalized indicator function analysis (GIFA).
Results—Vertical and craniocaudal propulsion peak forces and impulses did not differ significantly between days 1 and 2 or days 3 and 4. When data were compared between years, no significant differences were found for vertical impulse and craniocaudal propulsion peak force and impulse, but differences were detected for vertical peak force. The GIFA of the vertical and craniocaudal force-time waveforms identified significant interday and interyear differences. These results were identical for both hind limbs.
Conclusions and Clinical Relevance—Findings indicated that when comparing kinetic data overtime, additional insight may be gleaned from GIFA of the complete waveform, particularly when subtle waveform differences are present.
Objective—To evaluate the effects of firocoxib, meloxicam, and tepoxalin administration in healthy cats by measuring the ability of stimulated tissues to synthesize eicosanoids ex vivo.
Animals—8 healthy adult male cats.
Procedures—In a blinded, randomized, crossover study design, cats were treated with firocoxib (1 mg/kg, PO, q 24 h), meloxicam (0.05 mg/kg, PO, q 24 h), tepoxalin (5.0 mg/kg, PO, q 12 h), or a placebo for 8 days. Blood samples and gastric and duodenal mucosal biopsy specimens were collected on days 0 (baseline; immediately before treatment), 3, and 8 of each treatment period. Thromboxane B2 (TXB2) concentrations were measured in serum, and prostaglandin E2 (PGE2) and leukotriene B4 (LTB4) concentrations were measured in plasma. Prostaglandin E1 (PGE1) synthesis, PGE2 synthesis, and LTB4 concentrations were measured in mucosal biopsy specimens. A 21-day minimum washout period was observed between treatments. Repeated-measures analyses were performed.
Results—Firocoxib and meloxicam administration resulted in a lower plasma PGE2 concentration than at baseline on days 3 and 8 of administration, whereas tepoxalin administration did not. Tepoxalin administration resulted in a lower serum TXB2 concentration and pyloric and duodenal PGE1 synthesis on both days, compared with baseline and placebo administration. Neither firocoxib nor meloxicam administration altered pyloric or duodenal PGE1 synthesis on either day, compared with placebo administration. Tepoxalin administration also resulted in lower pyloric mucosal LTB4 concentrations on both days, compared with baseline values.
Conclusions and Clinical Relevance—Firocoxib and meloxicam administration had no effect on cyclooxygenase-1 activity, whereas tepoxalin administration resulted in inhibition of cyclooxygenase-1 and 5-lipoxygenase. (Am J Vet Res 2010;71:1067–1073)
ANIMALS 40 dogs with clinical osteoarthritis of the elbow or stifle joint.
PROCEDURES Dogs orally received 3 times/d (morning, midday, and night) for a 10-day period each of 3 identically appearing treatments (placebo; carprofen at 2.2 mg/kg [1 mg/lb], q 12 h [morning and night], with placebo at midday; or tramadol hydrochloride at 5 mg/kg [2.3 mg/lb], q 8 h) in random order, with treatment sessions separated by a minimum 7-day washout period. Vertical ground reaction forces (vertical impulse [VI] and peak vertical force [PVF]) were measured and Canine Brief Pain Inventory (CBPI) scores assigned prior to (baseline) and at the end of each treatment period. Repeated-measures ANOVA was performed to compare VI and PVF data among and within treatments, and the χ2 test was used to compare proportions of dogs with a CBPI-defined positive response to treatment.
RESULTS 35 dogs completed the study. No significant changes from baseline in VI and PVF were identified for placebo and tramadol treatments; however, these values increased significantly with carprofen treatment. Changes from baseline in VI and PVF values were significantly greater with carprofen versus placebo or tramadol treatment. A significant improvement from baseline in CBPI scores was identified with carprofen treatment but not placebo or tramadol treatment.
CONCLUSIONS AND CLINICAL RELEVANCE 10 days of treatment with tramadol as administered (5 mg/kg, PO, q 8 h) provided no clinical benefit for dogs with osteoarthritis of the elbow or stifle joint.
Objective—To evaluate the effects of ketamine, diazepam, and the combination of ketamine and diazepam on intraocular pressures (IOPs) in clinically normal dogs in which premedication was not administered.
Procedures—Dogs were randomly allocated to 1 of 5 groups. Dogs received ketamine alone (5 mg/kg [KET5] or 10 mg/kg [KET10], IV), ketamine (10 mg/kg) with diazepam (0.5 mg/kg, IV; KETVAL), diazepam alone (0.5 mg/kg, IV; VAL), or saline (0.9% NaCl) solution (0.1 mL/kg, IV; SAL). Intraocular pressures were measured immediately before and after injection and at 5, 10, 15, and 20 minutes after injection.
Results—IOP was increased over baseline values immediately after injection and at 5 and 10 minutes in the KET5 group and immediately after injection in the KETVAL group. Compared with the SAL group, the mean change in IOP was greater immediately after injection and at 5 and 10 minutes in the KET5 group. The mean IOP increased to 5.7, 3.2, 3.1, 0.8, and 0.8 mm Hg over mean baseline values in the KET5, KET10, KETVAL, SAL, and VAL groups, respectively. All dogs in the KET5 and most dogs in the KETVAL and KET10 groups had an overall increase in IOP over baseline values.
Conclusions and Clinical Relevance—Compared with baseline values and values obtained from dogs in the SAL group, ketamine administered at a dose of 5 mg/kg, IV, caused a significant and clinically important increase in IOP in dogs in which premedication was not administered. Ketamine should not be used in dogs with corneal trauma or glaucoma or in those undergoing intraocular surgery.
Objective—To investigate the effect of therapeutic dosages of meloxicam on the plasma clearance of iohexol in healthy, euvolemic, conscious cats fed a sodium-replete diet.
Animals—6 healthy adult neutered male cats.
Procedures—For each treatment period in a masked, randomized, crossover study, cats were administered either no treatment or meloxicam. Iohexol clearance studies were performed before the treatment period began (baseline) and on the final day of the treatment period. Iohexol concentrations were determined by use of a high-performance liquid chromatography assay, and plasma iohexol clearance as a marker of glomerular filtration rate was calculated by use of a 1-compartment model.
Results—No significant treatment effect was detected. Mean ± SE iohexol clearance for cats administered meloxicam (3.31 ± 0.27 mL/min/kg) was not significantly different from mean baseline value for the meloxicam treatment period (3.07 ± 0.32 mL/min/kg).
Conclusions and Clinical Relevance—In this study, short-term meloxicam administration did not measurably alter the glomerular filtration rate as assessed via plasma clearance of iohexol. This suggests that renal prostaglandins in cats did not have a measurable effect on glomerular filtration rates in healthy, euvolemic, conscious states as determined on the basis of methods used in this study.
Objective—To compare overground and treadmill-based gaits of dogs.
Animals —5 clinically normal adult mixed-breed dogs.
Procedures—To obtain dynamic gait data, 30 retroreflective markers were affixed bilaterally to specific regions of the hind limbs and pelvis of each dog. For each dog, 3-D joint motion data (sagittal [flexion and extension], transverse [internal and external rotation], and frontal [abduction and adduction] planes of motion) for the hip, femorotibial, and tarsal joints were acquired during walking and trotting through a calibrated testing space overground or on a treadmill. Comparison of data was performed via generalized indicator function analysis and Fourier analysis.
Results—Both overground and treadmill-based gaits produced similar waveforms in all planes of motion. Fourier analysis revealed no difference between overground and treadmill-based gaits in the sagittal plane of motion; however, small differences were detected between overground and treadmill-based gaits in the other 2 planes of motion. Additionally, femorotibial joint motion during walking did not differ among planes of motion. Generalized indicator function analysis was able to detect differences between overground and treadmill-based gait waveforms in all planes of motion for all joints during walking and trotting.
Conclusions and Clinical Relevance—In dogs, overground and treadmill-based gaits produced similar waveform shapes. Of the 3 planes of motion evaluated, only sagittal plane kinematic gait data were unaffected by mode of ambulation as determined via Fourier analysis. Sagittal kinematic gait data collected from dogs during overground or treadmill-based ambulation were comparable. However, analysis methods may affect data comparisons.
Case Description—A 1.5-year-old mixed-breed dog was examined because of a 1-month history of anorexia, vomiting, diarrhea, and weight loss.
Clinical Findings—The dog was very thin on physical examination (body condition score, 3/9). Results of all diagnostic tests were within reference limits except intestinal thickening and lymphadenopathy were identified on abdominal ultrasound examination. During exploratory laparotomy, thickening at the ileocecal-colic junction and within the transverse colon and mesenteric lymphadenopathy were identified, and the ileocecal-colic junction was resected. Histopathologic evaluation of the ileocecal-colic junction and full-thickness biopsy specimens from other sites as well as results of a serum ELISA were diagnostic for gastrointestinal Pythium insidiosum infection.
Treatment and Outcome—Pythiosis was initially treated medically with administration of itraconazole and terbinafine by mouth, but the colonic lesion was progressive with this regimen. Two months after diagnosis, a subtotal colectomy was performed; marginal excision (0.6 cm) was obtained at the aboral margin. The dog was treated with 3 doses of a pythiosis vaccine beginning approximately 2 weeks after surgery and was continued on itraconazole and terbinafine for 5 months. Parenteral and enteral nutrition as well as considerable general supportive care were required postoperatively. Six months after treatment, the dog had a normal serum ELISA titer. Two years after treatment, the dog had returned to preoperative weight and was clinically normal.
Clinical Relevance—This patient had an unusually positive therapeutic response to chronic, extensive, marginally excised gastrointestinal pythiosis.