Development of a perceived exertion scale for dogs using selected physiologic parameters.

OBJECTIVE: To develop a perceived exertion scale for dogs exercising on a treadmill and to assess intra- and inter-observer variability. MATERIALS AND METHODS: Fifteen healthy client-owned dogs participated in paired exercise trials. Measurements of lactate, glucose, heart rate, temperature, respiratory rate and regional tissue oximetry were obtained before, during and after exercise. Perceived exertion scale scores were recorded during exercise and using video recordings to evaluate inter-observer variability. Correlations were evaluated using the Spearman's non-parametric method. RESULTS: Thirteen dogs completed both trials. Dogs walked or trotted on the treadmill with an average perceived exertion score of 2 in both trials. Holter heart rate was positively correlated with perceived exertion scale scores from all observers for both trials. In trial 1, plasma glucose decreased in association with increase in perceived exertion and, in trial 2, cutaneous oximetry decreased, respiratory rate increased and temperature increased with increases on the perceived exertion scale. Inter-observer perceived exertion scale scores were positively correlated in both trials. There was no intra-observer variability between trials. CLINICAL SIGNIFICANCE: The perceived exertion scale correlated with the measured physiologic parameters in dogs exercising at mild to moderate intensity. The perceived exertion scale was consistent and repeatable but larger study numbers and further validation are needed before it can be widely applied.

Effects of dietary calcium fructoborate supplementation on joint comfort and flexibility and serum inflammatory markers in dogs with osteoarthritis.

Our objective was to evaluate the short-term effects of calcium fructoborate (CFB) on gait, joint range of motion, serum inflammatory markers, and owner perception of pain in client-owned dogs. We used 59 osteoarthritic dogs with impairment, with dogs being randomly assigned to 4 treatments: placebo (60 mg fructose; = 15), low dose (69 mg CFB; = 14), high dose (127 mg CFB; = 14), or combination (69 mg CFB, 500 mg glucosamine hydrochloride and 200 mg chondroitin sulfate; = 16). Dogs up to 22.9 kg received 1 capsule/d, while dogs weighing 23 to 50 kg received 2 capsules/d. A physical examination, radiographs, goniometry measurements, gait analysis, blood sample collection, and a canine brief pain inventory questionnaire were performed on d 0 and 28. Change from baseline values were statistically analyzed among groups. After 28 d, dogs fed the low and high doses had an improved ( < 0.05) ability to rise from a lying position compared to placebo. Dogs fed the high dose also had a greater ( = 0.05) increase in soluble receptor for advanced glycation end products concentration than dogs fed the placebo. Sub-analysis of only large dogs (> 23 kg) showed that dogs fed the low dose had decreased ( < 0.05) pain severity score and pain at its worst compared to dogs fed the placebo. Large dogs fed the low dose also were shown to improve ( < 0.05) in their ability to rise from a lying position compared to dogs fed the placebo. Overall, CFB supplementation was well-tolerated and may aid in mitigating joint discomfort in dogs.

Barbed versus smooth poly-propylene three-loop pulley sutures for repair of canine gastrocnemius tendon.

OBJECTIVE: To compare the ultimate tensile strength (UTS) and load to 1 and 3 mm gap formation of smooth (3-metric) and knotless barbed (4-metric) polypropylene sutures placed in a three-loop pulley pattern for canine gastrocnemius tendon repair. STUDY DESIGN: In vitro. SAMPLE SIZE: Thirty-three paired bone-tendon units with one of each pair assigned to each suture type. Barbed suture size was based on previously published materials testing results. METHODS: Each unit was placed in a servo-hydraulic testing machine and tested under single cycle tensile loading until repair failure. RESULTS: There was a significantly higher UTS for smooth polypropylene compared to the barbed polypropylene repairs. The loads resulting in 1 and 3 mm gaps for the barbed repairs were consistently significantly less than the corresponding smooth polypropylene repair values. CONCLUSION: The knotted smooth polypropylene repair was consistently stronger than the knotless barbed polypropylene repair when placed in a three-loop pulley pattern for gastrocnemius repair. CLINICAL SIGNIFICANCE: Knotless barbed polypropylene suture should not be considered equivalent to knotted smooth polypropylene of comparable tensile strength when placed in a three-loop pulley pattern for canine gastrocnemius tendon repair. The low failure loads of the barbed repair are probably due to failure of the barbs to anchor consistently throughout the tendon in the knotless configuration.

The effects of a novel lateral extracapsular suture system on the kinematics of the cranial cruciate deficient canine stifle.

OBJECTIVE: To evaluate the relative position of the femur and tibia in cranial cruciate ligament-intact stifles, cranial cruciate ligament-deficient stifles, and cruciate-deficient stifles following lateral extracapsular suture system (LESS) stabilization under load at specific joint angles. STUDY DESIGN: In vitro biomechanical study. METHODS: Twenty pelvic limbs from 11 dogs were used to evaluate the relative position of the femur and tibia between three stifle conditions (cranial cruciate ligament-intact, cranial cruciate ligament-deficient, and LESS-stabilized) at a load of 30% of body weight and stifle angles of 125°, 135°, and 145° using electromagnetic tracking sensors. RESULTS: Cranial cruciate ligament-deficient stifles had significantly greater (p <0.0001) cranial displacement and internal rotation of the tibia relative to the femur than cranial cruciate ligament-intact or LESS stifles at all stifle angles. Cranial displacement of the tibia relative to the femur for cranial cruciate ligament-intact and LESS stifles were not significantly different from one another at a stifle angle of 125°, but were significantly different at stifle angles of 135° (p = 0.0182) and 145° (p = 0.0012). There was no significant difference in internal rotation of the tibia relative to the femur between the cranial cruciate ligament-intact and LESS stifles at any of the stifle angles. CLINICAL SIGNIFICANCE: The LESS procedure effectively decreased cranial tibial displacement and eliminated internal rotation of the tibia relative to the femur in the cranial cruciate ligament-deficient stifles at stifle angles of 125°, 135°, and 145° in vitro.

Effect of tibial insertion site for lateral suture stabilization on the kinematics of the cranial cruciate ligament deficient-stifle during early, middle and late stance: an in vitro study.

OBJECTIVE: To evaluate the effect of two tibial attachment sites for lateral suture stabilization (LSS) on the three-dimensional femorotibial translational and rotational movements of the cranial cruciate ligament- deficient canine stifle during the early, middle and late stance phases. STUDY DESIGN: In vitro biomechanical study: 32 hindlimbs from 16 canine cadavers. METHODS: Limbs were mounted in a testing jig and an electromagnetic tracking system was used to determine the three-dimensional femorotibial translational and rotational movements under 33% of body weight load during early, middle and late stance in the following sequence: cranial cruciate ligament-intact, cranial cruciate ligament-deficient and LSS with the distal anchor through the tibial tuberosity (LSSTT) or through the cranial eminence of the extensor groove (LSSEG). The proximal anchor point was the lateral femorofabellar ligament. RESULTS: Post-LSS stifle three-dimensional femorotibial translational and rotational movements were more comparable to normal than post-transection movements for both techniques. Both LSS techniques restored femorotibial movements in cranial cruciate ligament-deficient stifles to varying amounts but neither technique successfully restored normal three-dimensional femorotibial movements. The LSSEG improved femorotibial movements of the cranial cruciate ligament-deficient stifle in the medial-lateral direction and axial rotation but performed poorly in restoring femorotibial movements in the cranial-caudal direction as compared to the LSSTT. CLINICAL SIGNIFICANCE: Both the LSSTT and LSSEG techniques failed to completely restore normal three-dimensional femorotibial translational and rotational movements in cranial cruciate ligament-deficient stifles in vitro.

Effect of stifle angle on the magnitude of the tibial plateau angle measurement in dogs with intact and transected cranial cruciate ligament. A cadaveric study.

OBJECTIVE: To determine the effect of stifle angle on the magnitude of the radiographic tibial plateau angle (TPA) in normal and cranial cruciate ligament (CCL) -deficient stifles. METHODS: Three pairs of canine cadaver hindlimbs from three skeletally mature dogs were positioned in a custom-made positioning device. A lateral radiograph of each specimen was obtained before and after transection of the CCL at four stifle angles (90°, 110°, 135° and 140-150° [i.e. maximum extension]), based on goniometric measurements. Four observers determined the radiographic TPA twice for each radiograph with a minimum of two days between each measurement. The radiographic TPA measurements in all specimens at different stifle angles with intact CCL and transected CCL were compared with mixed-model ANOVA. The effect of stifle angle, CCL transection, and interaction between the two on observer TPA measurement variability was also determined using the coefficient of variation. RESULTS: Tibial plateau angle was not statistically different in the stifle angles for either the intact or transected CCL. There was also no statistical difference for TPA between intact and transected CCL groups at each of the stifle angles. Stifle angle, CCL transection and interaction between the two did not have any significant effect for intra-observer and inter-observer variation. CLINICAL SIGNIFICANCE: The angle of the stifle during radiography does not influence the magnitude of the TPA measurement as determined on true lateral radiographs of the stifle and tibia in cadaveric canine limbs.

A collaborative study on the suitability of commercial, assayed plasmas for one-stage factor VIII assays.

A collaborative study was carried out to determine the suitability of commercial assayed plasmas for one-stage factor VIII assays. Activated partial thromboplastin times were performed on successive days on serially diluted paired freeze-dried reference plasmas (one sample buffered with HEPES), a freeze-dried test plasma and local laboratory standards-commercial assayed plasmas and in-house frozen pooled plasmas calibrated against commercial plasmas. The factor VIII activity levels of the study reference plasmas relative to average normal plasma were arrived at cumulatively by assaying them against a large number of individual fresh normal plasmas. Estimates of the activity of the test plasma relative to the claimed activity of local standards showed significant discrepancies from the expected value. However the estimates were more precise when the activity was assessed relative to the activity of the local standards derived by calibration against the reference plasmas. The study also showed that a HEPES buffered reference plasma may not contribute to inter-laboratory variability of one-stage factor VIII assays.

Reliability of "standard" plasmas used by clinical laboratories for one-stage factor VIII assays.

The reliability of "standard" plasmas used by clinical laboratories to assay factor VIII concentrations of patients' plasmas was studied by assessing the credibility of their reference values. Two of three commercial reference plasmas were considered to be unreliable. The third commercial reference plasma appeared to be suitable when assayed against frozen pools of fresh normal plasma with an assigned value of 100% activity. However, assays using fresh pools of normal plasma suggested that the reference value may lack credibility. This study also showed that assignment of 100% activity to frozen pools of fresh normal plasma prepared locally in laboratories may be fallacious.

The "therapeutic range" of the one-stage prothrombin time in the control of anticoagulant therapy: the effect of different thromboplastin preparations.

Commercially available thromboplastin reagents and two human brain preparations have been compared using the one-stage prothrombin time and plasma samples from patients receiving long-term oral anticoagulant therapy. Considerable variation is noted between various thromboplastins using the same plasma sample. The commercially available thromboplastins give shorter prothrombin times than do human brain preparations. With the latter, the "therapeutic range" is represented by a prothrombin time of about 1.8 to 3.0 times the normal control value, whereas with commercial preparations the "therapeutic range" is about 1.25 to 1.75 times normal. The implications of these observations are discussed; the desirability of standardization of the one-stage prothrombin time is emphasized.