You are looking at 1 - 3 of 3 items for
- Author or Editor: Michael A. Weishaupt x
- Refine by Access: All Content x
Objective—To evaluate the effects of shock wave treatment on cutaneous nerve function, compared with the effects of local nerve block and sedation.
Animals—18 clinically sound Swiss Warmbloods.
Procedure—Horses were randomly allocated to 3 groups and received different amounts and types of shock waves (extracorporeal shock wave treatment [ESWT] or radial pressure wave treatment [RPWT]). Horses were sedated with xylazine and levomethadone. Shock waves were applied to the lateral palmar digital nerve at the level of the proximal sesamoid bones on 1 forelimb. Skin sensitivity was evaluated by means of an electrical stimulus at the coronary band before and 5 minutes after sedation and at 4, 24, and 48 hours after application of ESWT or RPWT. On the contralateral forelimb, skin sensitivity was tested before and 10 minutes after an abaxial sesamoid nerve block.
Results—No significant changes in skin sensitivity were detected, regardless of the shock wave protocol applied. Mean reaction thresholds after sedation were more than twice the baseline thresholds. After the abaxial sesamoid block, no reaction was recorded in any of the horses.
Conclusions and Clinical Relevance—Application of ESWT or RPWT to the palmar digital nerve had no effect on cutaneous sensation distal to the treated region for at least 2 days after application. The analgesic effect of sedation on reaction to electrical stimuli was distinct but varied among horses. (Am J Vet Res 2005;66:2095–2100)
OBJECTIVE To compare gait mechanics and limb loading in Icelandic horses tölting and trotting at equal speeds and estimate their impact on orthopedic health.
ANIMALS 12 orthopedically normal Icelandic horses.
PROCEDURES Kinetic and kinematic gait variables were simultaneously recorded as each horse was ridden at a tölt and trot on an instrumented treadmill at 3.4 m/s and 3.9 m/s. Differences between gaits were tested via 1-factor repeated-measures ANOVA.
RESULTS Horses had a higher stride rate and lower stride impulses at a tölt than at a trot. For forelimbs at a tölt, shorter relative stance duration resulted in higher peak vertical force (Fzpeak). Conversely, for hind limbs, longer relative stance duration resulted in lower Fzpeak. The higher head-neck position at a tölt versus trot caused no weight shift to the hind limbs, but a higher forehoof flight arc and lower proretraction movement were identified. Stance durations for forelimbs were briefer than for hind limbs at a tölt, and the inverse was observed at a trot. Minimal height of the horse's trunk at the point of Fzpeak of the respective limb suggested a spring-like mechanism for all limbs at a tölt. Hind limb measurements revealed no evidence of increased collection. Stride-to-stride limb timing varied more at a tölt than at a trot. At a trot, horses had brief or no suspension phases and a slightly 4-beated footfall rhythm was common. Post hoc energetic estimations revealed that tölting at the measured speeds was less advantageous than trotting.
CONCLUSIONS AND CLINICAL RELEVANCE High forelimb action in Icelandic horses and higher head-neck position at a tölt were associated with more restricted limb proretraction, higher Fzpeak, and faster force onset than at a trot. The impact of these differences on orthopedic health needs to be investigated more in detail.
Objective—To develop and validate a novel instrumented treadmill capable of determining vertical ground reaction forces of all 4 limbs simultaneously in horses.
Sample Population—Data obtained while a horse was walking and trotting on the treadmill.
Procedure—18 piezo-electric force transducers were mounted between the treadmill frame and supporting steel platform to measure the actual forces at the corresponding bearing points. Each of the 18 sensor forces is equal to the sum of the unknown hoof forces weighted with the transfer coefficients of the corresponding force application points. The 4 force traces were calculated, solving at each time point the resulting equation system, using the Gaussian least-squares method. System validation comprised the following tests: determination of the survey accuracy of the positioning system, determination of the natural frequencies of the system, linearity test of the force transfer to the individual sensors, determination of superimposed forces with the treadmill-integrated force measuring system (TiF) in a static configuration, and comparison of vertical ground reaction forces determined simultaneously by use of TiF and force shoes mounted on the forelimbs of a horse.
Results—Comparison between static test loads and TiF-calculated forces revealed deviations of < 1.4%. Force traces of TiF-calculated values and those recorded by use of the force shoes were highly correlated ( r ≥ 0.998).
Conclusions and Clinical Relevance—This instrumented treadmill allows a reliable assessment of load distribution and interlimb coordination in a short period and, therefore, is suitable for use in experimental and clinical investigations. (Am J Vet Res 002;63:520–527).