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1.
OBJECTIVE: To identify hind limb and pelvic kinematic variables that change in trotting horses after induced lameness of the distal intertarsal and tarsometatarsal joints and after subsequent intra-articular administration of anesthetic. ANIMALS: 8 clinically normal adult horses. PROCEDURE: Kinematic measurements were made before and after transient endotoxin-induced lameness of the distal intertarsal and tarsometatarsal joints and after intra-articular administration of anesthetic. Fourteen displacement and joint angle (metatarsophalangeal [fetlock] and tarsal joints) measurements were made on the right hind limb, sacrum, and the right and left tubera coxae. Kinematic measurements were compared by general linear models, using a repeated measures ANOVA. Post hoc multiple comparisons between treatments were evaluated with a Fisher least squared difference test at alpha = 0.05. RESULTS: After lameness induction, fetlock and tarsal joint extension during stance decreased, fetlock joint flexion and hoof height during swing increased, limb protraction decreased, and vertical excursion of the tubera coxae became more asymmetric. After intra-articular administration of anesthetic, limb protraction returned to the degree seen before lameness, and vertical excursion of the tubera coxae became more symmetric. CONCLUSIONS AND CLINICAL RELEVANCE: Increased length of hind limb protraction and symmetry of tubera coxae vertical excursion are sensitive indicators of improvement in tarsal joint lameness. When evaluating changes in tarsal joint lameness, evaluating the horse from the side (to assess limb protraction) is as important as evaluating from the rear (to assess pelvic symmetry).  相似文献   

2.
The effects of balancing the foot and shoeing (B&S) on the kinematics of five Quarter Horses with navicular disease were evaluated using computerized gait analysis. Kinematic measurements of the right forelimb and head were made before and after palmar digital nerve block (PDNB) and before and after B&S of the forelimb feet. Carpal and fetlock joint angle, foot displacement, and temporal gait measurements were made for at least five strides in each horse trotting on a treadmill. Kinematic measurements were compared before and after PDNB and before and after B&S by analysis of variance with an α=0.05. The most significant kinematic changes seen after PDNB were in the vertical head movement parameters studied. Total vertical head excursion and measures of head height asymmetry between right and left forelimb stance phases decreased after PDNB. After B&S mean carpal flexion and maximum hoof height during the swing phase of the stride increased, but none of the head movement parameters significantly changed. Results of this study indicate that the ability of treadmill kinematic gait analysis to evaluate for improvement in lameness by monitoring vertical head movement parameters is not significantly affected in horses with navicular disease three weeks after balancing and shoeing the forelimb feet.  相似文献   

3.
AIMS: To determine the frontal plane position of the ground reaction force vector at its centre of pressure under the hoof of walking horses, and its projection through the distal limb joints, and to relate this to hoof geometric measurements.

METHODS: Reflective markers were glued to the forelimb hooves and skin of 26 horses, over palpable landmarks representing centres of the coffin, fetlock and carpal joints, and the dorsal toe at its most distal point. A 4-camera kinematic system recorded the position of these markers as the horse walked in hand across a force platform, to generate a frontal plane representation of the ground reaction force vector passing between the markers at the joints. The position of the vector was calculated as the relative distance between the lateral (0%) and medial (100%) markers at each joint. Digital photos were taken of the hoof in frontal and sagittal views to determine hoof geometric measurements. Associations between these and the position of the force vector at each joint were examined using Pearson correlation coefficients.

RESULTS: Mean vector position for both forelimbs at the toe, coffin, fetlock and carpal joint was 50.1 (SD 8.9), 53.0 (SD 9.2), 54.6 (SD 11.4) and 50.5 (SD17.3)%, respectively, of the distance between the lateral and medial sides of the joint in the frontal plane. Across all four joints, the vector position was slightly more medial (2–4%) for the right than left limb (p>0.05). Medial hoof wall angle was correlated (p<0.05) with force vector position at the fetlock (r=?0.402) and carpal (r=?0.317) joints; lateral hoof wall angle with vector position at the toe (r=0.288) and carpal (r=?0.34) joint, and medial hoof wall height with vector position at the fetlock (r=?0.306) and carpal (r=?0.303) joints.

CONCLUSION: The position of the two-dimensional frontal plane ground reaction force vector at the toe, and at the fetlock and carpal joints was associated with hoof shape. Mediolateral hoof balance has been shown in vitro to affect articular forces, which may be a factor in development of joint disease. The effect of hoof shape needs to be evaluated at faster gaits to determine the potential for joint injury in the presence of larger forces.  相似文献   

4.
OBJECTIVE: To determine the mechanism that enables horses to partially counteract the shift of the center of pressure under the hoof induced by changes in hoof morphology attributable to growth and wear during a shoeing interval. ANIMALS: 18 clinically sound Warmblood horses. PROCEDURES: Horses were evaluated 2 days and 8 weeks after shoeing during trotting on a track containing pressure-force measuring plates and by use of a synchronous infrared gait analysis system set at a frequency of 240 Hz. All feet were trimmed toward straight alignment of the proximal, middle, and distal phalanges and shod with standard flat shoes. Results-Temporal characteristics such as stance time and the time between heel lift and toe off (ie, breakover duration) did not change significantly as a result of shoeing interval. Protraction and retraction angles of the limbs did not change. Compensation was achieved through an increase in the dorsal angle of the metacarpohalangeal or metarsophalangeal (fetlock) joint and a concomitant decrease of the dorsal angle of the hoof wall and fetlock. There was an additional compensatory mechanism in the hind limbs during the landing phase. CONCLUSIONS AND CLINICAL RELEVANCE: Horses compensate for changes in hoof morphology that develop during an 8-week shoeing interval such that they are able to maintain their neuromuscular pattern of movement. The compensation consists of slight alterations in the angles between the distal segments of the limb. Insight into natural compensation mechanisms for hoof imbalance will aid in the understanding and treatment of pathologic conditions in horses.  相似文献   

5.
The objective was to study associations between kinematics and ground reaction forces in the hindlimb of walking horses. Video (60 Hz) and force (2000 Hz) data were gathered for 8 strides from each of 5 sound horses during the walk. Sagittal plane kinematics were measured concurrently with the vertical and longitudinal ground reaction forces. The hindlimb showed rapid loading and braking in the initial 10% stride. The stifle, tarsal and coffin joints flexed and the fetlock joint extended during this period of rapid loading. The vertical ground reaction force showed 2 peaks separated by a dip; this pattern was similar to the fetlock joint angle-time graph. Peaks in the longitudinal ground reaction force did not appear to correspond with kinematic events. Total braking impulse was equal to total propulsive impulse over the entire stride. Flexion and extension of the hip were responsible for protraction and retraction of the entire limb. Maximal protraction occurred shortly before the end of swing and maximal retraction occurred during breakover. During the middle part of stance the tarsal joint extended slowly, while the stifle began to flex when the limb was retracted beyond the midstance position at 28% stride. Flexion cycles of the stifle and tarsal joints were well coordinated during the swing phase to raise the distal limb as it was protracted. The results demonstrate a relationship between limb kinematics and vertical limb loading in the hindlimbs of sound horses. Future studies will elucidate the alterations in response to lameness.  相似文献   

6.
Summary

The kinematic pattern of mild bilateral lameness was studied by inducing a supporting limb lameness in both forelimbs of 11 sound Dutch Warmblood horses. The kinematics of the horses were recorded while they trotted (3.5 m/s) on a treadmill. The locomotion analysis system CODA‐3 was used to determine the temporal stride patterns, limb movements as well as head and trunk movement patterns. The transient lameness model, by which pressure‐induced pain is evoked on the hoof sole, was used. Differences between left and right limbs as well as between the sound and the lame condition were tested using a paired t‐test.

Stride and stance duration did not change significantly (p < 0.05) during bilateral lameness compared to the pattern of sound horses. Diagonal advanced placement changed to an earlier placement of both forelimbs. Fetlock hyperextension decreased also in both forelimbs, while the pro‐ and retraction, hoof impact angle, maximal hoof height, and all hind limb variables remained unchanged. Vertical head and trunk movements tended to decrease, but these changes were not significant.

It was concluded that fetlock hyperextension and diagonal advanced placement indicate locomotor disturbances, but that mild bilateral lameness may be difficult to distinguish from individual patterns in single assessments because of the lack of locomotor asymmetries. Evaluation of these variables at regular intervals may allow an early detection of bilateral lameness, which then could be confirmed by diagnostic local anaesthesia.  相似文献   

7.
Video (60 Hz) and force (2000 Hz) data were collected from 5 sound horses during walking. Forelimb data were analysed for 8 strides (4 left, 4 right) per horse to determine sagittal plane kinematics and ground reaction forces (GRFs). The results suggested that brachial rotation was responsible for protraction and retraction of the limb as a whole, while rotations of the scapula and antebrachium elevated the distal limb during breakover and early swing then lowered it in preparation for ground contact. The coffin joint was flexed maximally at the time of peak longitudinal braking force, which occurred during breakover of the contralateral forelimb. The metacarpus was vertical at 28% stride. This was considerably earlier than the change from a braking to a propulsive longitudinal force (34% stride), which coincided with maximal extension of the fetlock joint. The longitudinal propulsive force peaked just after contact of the contralateral forelimb. During the swing phase the joints distal to the shoulder showed a single flexion cycle that peaked at 76% stride at the carpus, 81% stride at the fetlock and 84% stride at the elbow and coffin joints. The coffin and shoulder joints began to extend in the terminal swing phase and continued to extend through ground contact and early stance. The results provide normative data that will be applied in detecting changes in kinematics and ground reaction forces that are associated with specific lamenesses.  相似文献   

8.
Orthopaedic shoeing applied for disorders such as navicular disease is mostly evaluated on hard track surfaces, but very often horses are ridden only on soft tracks. To compare the effects of normal shoes, eggbar shoes, and shoes with heel wedges (5 degrees) on the kinematics of the distal forelimb on hard and soft track surfaces, eleven sound Dutch Warmblood horses were led across three different tracks (an asphalt, a fibre/sand mix (= Agterberg), and a pure sand track) with three different shoe types (a normal shoe, an eggbar shoe, and a shoe with heel wedges). The hoof rotation and the maximal extension of the fetlock joint at midstance period were recorded by an infrared-light based gait analysis system (ProReflex) at walk and at trot. Statistical analysis revealed significant effects of track and shoe type, and a shoe-track interaction (p<0.05). On soft track surfaces, the equilibrium of the distal forelimb dictated a 1.5-4 degrees forward rotation of the normal or eggbar shod foot, the most on a sand track. The wedge effect on hoof rotation, however, was always significantly greater, but similar to that on the hard track surface (5 degrees forward rotation). The maximal fetlock extension was less on a soft surface, in particular on the sand track (p<0.05). This decrease was most pronounced when the horses were shod with heel wedges and was least pronounced with normal shoes. In conclusion, in particular the sand track allows a forward rotation of the hoof and thus relief of pressure in the navicular area, and a decrease in maximal fetlock extension and thus unloading of the fetlock joint. The extra forward rotation of the hoof induced by heel wedges on hard tracks was almost the same on soft track surfaces. Eggbars and fibre/sand mix tracks have intermediate effects on unloading of the distal forelimb.  相似文献   

9.
REASONS FOR PERFORMING STUDY: Comprehensive understanding of the 3-dimensional (3D) kinematics of the distal forelimb and precise knowledge of alterations induced by dorsopalmar foot imbalance remains incomplete because in vivo studies performed with skin markers do not measure the actual movements of the 3 digital joints. OBJECTIVE: To quantify the effects of 6 degree heel or toe wedges on the 3D movements of the 4 distal segments of the forelimb in horses trotting on a treadmill. METHODS: Three healthy horses were equipped with ultrasonic markers fixed surgically to the 4 distal segments of the left forelimb. The 3D movements of these segments were recorded while horses were trotting on a treadmill. Rotations of the digital joints were calculated by use of a joint coordinate system. Data obtained with 6 degree heel or toe wedges were compared to those obtained with flat standard shoes. RESULTS: Use of heel wedges significantly increased maximal flexion and decreased maximal extension of the proximal (PIPJ) and distal (DIPJ) interphalangeal joints. Inverse effects (except for PIPJ maximal extension) were observed with the toe wedges. In both cases, neither flexion-extension of the metacarpophalangeal joint nor extrasagittal motions of the digital joints were statistically different between conditions. CONCLUSIONS: At a slow trot on a treadmill, heel and toe wedges affect the sagittal plane kinematics of the interphalangeal joints. POTENTIAL RELEVANCE: Better understanding of the actual effects of toe and heel wedges on the 3D kinematics of the 3 digital joints may help to improve clinical use of sagittal alteration of hoof balance in the treatment of distal forelimb injuries.  相似文献   

10.
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11.
REASONS FOR PERFORMING STUDY: The compensatory mechanisms of horses with weightbearing hindlimb lameness are still not fully understood. HYPOTHESIS: That weightbearing, unilateral hindlimb lameness would not only alter stride characteristics to diminish structural stress in the affected limb but also induce compensatory load adjustments in the other supporting limbs. OBJECTIVE: To document the load and time shifting mechanisms of horses with unilateral weightbearing hindlimb lameness. METHODS: Reversible lameness was induced in 8 clinically sound horses by applying a solar pressure model. Three degrees of lameness (subtle, mild and moderate) were induced and compared with the nonlame (sound) control measurement. Vertical ground reaction forces were recorded for all 4 limbs simultaneously on an instrumented treadmill. RESULTS: Compared to the sound situation, moderate hindlimb hoof lameness induced a decrease in stride duration (-3.3%) and stride impulse (-3.1%). Diagonal impulse decreased selectively in the lame diagonal stance (-7.7%). Within the diagonal limb pair, vertical impulse was shifted to the forelimb during the lame diagonal stance (+6.5%) and to the hindlimb during the sound diagonal stance (+3.2%). Peak vertical force and vertical impulse decreased in the lame limb (-15%), but only vertical impulse increased in the contralateral hindlimb (+5.7%). Stance duration was prolonged in both hindlimbs (+2.5%). Suspension duration was reduced to a greater extent after push-off of the lame diagonal limb pair (-21%) than after the sound diagonal limb pair (-9.2%). CONCLUSIONS: Four compensatory mechanisms could be identified that served to reduce structural stress, i.e. peak vertical force on the affected limb: 1) reduction of the total vertical impulse per stride; 2) diagonal impulse decreased selectively in the lame diagonal; 3) impulse was shifted within the lame diagonal to the forelimb and in the sound diagonal to the hindlimb; and 4) the rate of loading and peak forces were reduced by prolonging the stance duration. POTENTIAL RELEVANCE: Load shifting mechanisms are not only effective in diminishing peak forces in the affected limb, but also suppress compensatory overload in other limbs. Selected force and time parameters allow the unequivocal identification of the lame limb. Future studies have to examine how far these compensatory mechanisms may be generalised for other defined orthopaedic problems in the hindlimb.  相似文献   

12.
REASONS FOR PERFORMING STUDY: Support boots are thought to reduce tension on the superficial digital flexor tendon (SDTF) of the horse and are frequently recommended for horses convalescing after tendonitis, but evidence of their effectiveness is conflicting. OBJECTIVE: To document the effects of 4 different types of support boots on fetlock joint angle in comparison to the unprotected fetlock. METHODS: In 26 horses, the kinematics of the forelimb fetlock joint angle was measured at walk and trot on a treadmill when wearing 3 different types of support boots and 1 protective boot, as well as without boots. As outcome parameters, maximum extension of the fetlock joint and the moment at which maximum extension occurred in the stride cycle were determined. RESULTS: At walk, 2 of the support boots reduced the maximum extension significantly by 0.8 and 0.9 degrees, respectively (P<0.05). Additionally, one type of boots also delayed the occurrence of maximal extension within the stride cycle. At trot, all support boots reduced maximum extension significantly by 0.56-1.44 degrees (P<0.01), and the protective boot reduced maximum extension by 0.56 degrees (P<0.05). CONCLUSIONS AND POTENTIAL RELEVANCE: The results demonstrate the effectiveness of support boots in reducing maximum extension of the fetlock, which can be assumed to reduce tension in the suspensory apparatus and SDFT. The delay of the moment of maximal extension may be relevant in reducing dynamic forces. However, it should be noted that the long-term consequences of reduction of maximum fetlock extension are still uncertain. Such a reduction over a prolonged period might negatively affect fibre alignment in the healing tendon.  相似文献   

13.
OBJECTIVE: To investigate continuous wavelet transformation and neural network classification of gait data for detecting forelimb lameness in horses. ANIMALS: 12 adult horses with mild forelimb lameness. PROCEDURE: Position of the head and right forelimb foot, metacarpophalangeal (ie, fetlock), carpal, and elbow joints was determined by use of kinematic analysis before and after palmar digital nerve blocks. We obtained 8 recordings from horses without lameness, 8 with right forelimb lameness, and 8 with left forelimb lameness. Vertical and horizontal position of the head and vertical position of the foot, fetlock, carpal, and elbow joints were processed by continuous wavelet transformation. Feature vectors were created from the transformed signals and a neural network trained with data from 6 horses, which was then tested on the remaining 2 horses for each category until each horse was used twice for training and testing. Correct classification percentage (CCP) was calculated for each combination of gait signals tested. RESULTS: Wavelet-transformed vertical position of the head and right forelimb foot had greater CCP (85%) than untransformed data (21%). Adding data from the fetlock, carpal, or elbow joints did not improve CCP over that for the head and foot alone. CONCLUSIONS AND CLINICAL RELEVANCE: Wavelet transformation of gait data extracts information that is important for the detection and differentiation of forelimb lameness of horses. All of the necessary information to detect lameness and differentiate the side of lameness can be obtained by observation of vertical head movement in concert with movement of the foot of 1 forelimb.  相似文献   

14.
Linear, temporal and angular biokinematic characteristics of the forelimb at the walk in different breeds were determined, highlighting inter-breed differences. Twenty-three healthy stallions were used: ten Andalusians (AN), seven Arabs (AR) and six Anglo-Arabs (AA). Height at the withers was significantly different between groups (P < 0.001). Six trials per horse were recorded using a levelled video camera (sampling frame rate 25 frames/s), digitized and analysed using a semi-automatic movement analysis system. No statistically significant differences in speeds were recorded between breeds (P > 0.05). The only temporal parameter which was similar in the three breeds was the moment at which the hoof reached the highest point in its trajectory. The variables presenting the most significant differences were the percentages of deceleration and propulsion within the stance phase. ANOVA for angular variables showed that the greatest difference was in the range of angular movement of the carpal joint, being higher in AN, due to a lower minimum value. In the fetlock joint, the greatest difference was observed in minimum values, which differed in all three breeds. Significant inter-breed differences were also observed for maximum limb retraction, being lowest in the AN group, followed by the AA and AR groups. This finding was reflected in the angular range of motion, despite smaller differences in the degree of limb protraction; very similar values were reported in all three breeds. As regards the elbow joint, no inter-breed differences were observed in terms of minimum values, whereas differences were recorded for maximum and angular range of motion, higher values being displayed by the AR and AN groups than by AA animals. In conclusion, inter-breed differences may be determined in equine forelimb biokinematics at the walk. This study distinguished between AN, AR and AA horses.  相似文献   

15.
A recent epidemiological study indicated that various factors may be related to injury in dressage horses, but the mechanism by which these injuries occur has yet to be determined. The suspensory ligament (SL) is a frequent site of injury, and it is assumed that greatest strain is placed on this structure in collected trot; this has yet to be proved conclusively. The study aimed to investigate the effect of collected and extended trot on the hindlimb movement pattern. Four dressage horses were fitted with markers and inertial motion sensors (IMS). High‐speed video was obtained for 2 strides on each rein in collected and extended trot on 3 different surfaces: waxed outdoor; sand/plastic granules; and waxed indoor. Maximal tarsal flexion during stance and distal metatarsal coronary band ratio (MTCR), representing fetlock extension, were determined. Inertial motion sensor data determined stride duration, speed and stride length. Data were compared between collection and extension within horses on each surface, and compared between surfaces. Collected trot had significantly lower speed and stride length but longer stride duration than extended trot on all surfaces. All horses had less tarsal flexion and fetlock extension in collected compared with extended trot (P<0.05), which is likely to increase SL loading. The study findings indicate that extended trot may increase SL strain, providing a possible explanation for the high incidence of SL injury in horses trained for extravagant movement. It is possible that substantial use of extended trot could be a risk factor for development of suspensory desmitis, which might be one contributory factor in the prevalence of suspensory desmitis in young horses repeatedly undertaking extravagant movement.  相似文献   

16.
To meet the needs of sport horses, horseshoes of various styles and materials have been implemented to enhance performance. Steel shoes are commonly used for their affordability and longevity; however, the use of aluminum horseshoes is being adopted to satisfy the various requirements of certain equestrian activities. Owing to the importance of the allure of movement in many aspects of competitive riding, the lightweight nature of aluminum horseshoes has been recognized to accentuate foreleg action. By performing a repeated-measures crossover study on nine healthy stock-type horses, the effects of these two horseshoe types on forelimb action were analyzed at the trot using two-dimensional kinematics. Horses were trotted in hand for three repetitions over a distance of 50.1 meters on days 4, 18, 32, and 46 postshoeing for two 6-week shoeing cycles. Video footage was collected and analyzed using gait analysis software (EquineTec) for each repetition. The measured stride length, fetlock extension, elbow and knee range of motion, and minimum and maximum elbow angle remained constant between treatments. However, there was a significant treatment effect on minimum carpal angle and maximum hoof height, with aluminum shoes having a larger minimum carpal angle than those in steel shoes (P < .05) and a lower maximum hoof height (P < .05). An overall 3-degree difference in minimum carpal angle and approximate 2.5-cm difference in maximum hoof height was observed between treatments. This finding is of particular importance to performance horse disciplines for which a lesser degree of knee action is desirable.  相似文献   

17.
Navicular disease results in a chronic, progressiveforelimb lameness that is usually bilateral. Although many different horse breeds can be affected, Quarter Horses and Warmbloods appear particularly susceptible. The peak age incidence appears to be in horses aged 6–10 years. The condition has been recognized for many years and has been the source of debate and conflict for at least the last 50 years. Much of the confusion has been caused by different criteria used to establish a diagnosis. In a large series of cases examined at the University of Sydney, only 30 percent of horses that were eventually diagnosed as having navicular disease showed a positive response to hoof testers applied across the middle third of the frog. In contrast, more than 80 percent of horses with navicular disease showed a marked increase in lameness following pastern and fetlock flexion. All horses diagnosed became sound following a palmar digital nerve block and all had positive findings on radiography. However, radiography could not be utilized as a sole diagnostic technique because some horses with radiographic abnormalities of the navicular bone did not show clinical signs of navicular disease.To establish a diagnosis of navicular disease, the following criteria should be met: 1) A chronic progressive unilateral or bilateral forelimb lameness, 2) Pain in areas proximal to the foot has been excluded as a possible cause of the lameness, 3) Other conditions that could cause pain in the palmar heel region are excluded, 4) The lameness is eliminated or substantially improved following a palmar digital nerve block, and 5) There are radiographic abnormalities on upright pedal and/or skyline views of the navicular bone.Treatment of navicular disease has usually fallen into categories of a) pain alleviation, b) drugs with vascular or hemodynamic effects, or c) changing biomechanics either by corrective trimming or corrective shoeing. None of these treatments have been universally accepted and debate about their efficacy is allied to theories about the etiology.  相似文献   

18.
OBJECTIVE: To evaluate pelvic movement over a large number of strides in sound horses and in horses with induced hind limb lameness by applying methods to the pelvis that have been described for evaluating vertical head movement in horses with induced forelimb lameness. ANIMALS: 17 adult horses. PROCEDURE: Horses were filmed while trotting on a treadmill before and after induction of transient mild and moderate hind limb lamenesses. Vertical pelvic movement was measured by a signal decomposition method. The vertical pelvic signal was decomposed into a periodic component (A1) that occurred at half the stride frequency (representing vertical pelvic movement caused by lameness) and another periodic component (A2) that occurred at stride frequency (representing normal vertical pelvic movement of a trotting horse). Vertical pelvic and foot positions were correlated for each stride to compare the difference between the minimum and maximum heights of the pelvis during and after stance of the right hind limb to the minimum and maximum heights of the pelvis during and after stance of the left hind limb. RESULTS: Maximum pelvic height difference and lameness amplitude (A1) differed significantly between sound and mild or moderate hind limb lameness conditions. Mean A1 value for vertical pelvic movement in sound horses was less than that previously reported for vertical head movement. CONCLUSION AND CLINICAL RELEVANCE: Pelvic height differences and signal decomposition of pelvic movement can be used to objectively evaluate hind limb lameness in horses over a large number of strides in clinical and research settings.  相似文献   

19.
Point of breakover, defined as the portion of the hoof last in contact with the ground during the terminal stance phase of a limb, can be influenced by many factors including craniocaudal placement of the shoe. Shortening the point of breakover has been suggested to decrease strain on the deep digital flexor tendon and navicular bone as well as to improve the alignment of the second and third phalanx. The current experiment involved eight sound horses fitted with aluminum plates adhered to their front hooves, which were drilled and tapped to allow additional aluminum plates of various lengths to be attached (the longest plate was placed flush with the toe, while the shortest plate was moved 3.81 cm caudal to the toe). Horses were recorded on video while at the walk and trot over a distance of 70 meters for six repetitions to determine differences in gait kinematics. Results of this study show significant changes in stride kinematics caused by shortening the point of breakover. Retraction of the forelimbs was greatest when breakover was moved 1.27 cm back from the toe (P < .05), and minimum height of the fetlock at the trot was higher on all treatments where the breakover point was moved caudally (P < .05). Some improvements in gait quality were observed when breakover was shortened, although extreme caudal placement of the shoe (negative placement in relation to P3) resulted in a decrease in gait quality as seen by decreased retraction of the forelimb (P < .05) coupled with hoof height occurring earlier in the stride (P < .05).  相似文献   

20.
OBJECTIVE: To determine whether a shoe with an axialcontoured lateral branch would induce greater lateral roll of the forelimb hoof during the time between heel and toe lift-off at end of the stance phase (breakover). Animals-10 adult horses. PROCEDURE: A gyroscopic transducer was placed on the hoof of the right forelimb and connected to a transmitter. Data on hoof angular velocity were collected as each horse walked and trotted on a treadmill before (treatment 1, no trim-no shoe) and after 2 treatments by a farrier (treatment 2, trim-standard shoe; and treatment 3, trim-contoured shoe). Data were converted to hoof angles by mathematical integration. Breakover duration was divided into 4 segments, and hoof angles in 3 planes (pitch, roll, and yaw) were calculated at the end of each segment. Multivariable ANOVA was performed to detect differences among treatments and gaits. RESULTS: Trimming and shoeing with a shoe with contoured lateral branches induced greater mean lateral roll to the hoof of 3.2 degrees and 2.5 degrees during the first half of breakover when trotting, compared with values for no trim-no shoe and trim-standard shoe, respectively. This effect dissipated during the second half of breakover. When horses walked, lateral roll during breakover was not significantly enhanced by use of this shoe. CONCLUSIONS AND CLINICAL RELEVANCE: A shoe with an axial-contoured lateral branch induced greater lateral roll during breakover in trotting horses, but change in orientation of the hoof was small and limited to the first half of breakover.  相似文献   

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