Functional Locomotor Consequences of Uneven Forefeet for Trot Symmetry in Individual Riding Horses

ABSTRACT: Left-right symmetrical distal limb conformation can be an important prerequisite for a successful performance, and it is often hypothesized that asymmetric or uneven feet are important enhancing factors for the development of lameness. On a population level, it has been demonstrated that uneven footed horses are retiring earlier from elite level competition, but the biomechanical consequences are not yet known. The objectives of this study were to compare the functional locomotor asymmetries of horses with uneven to those with even feet. Hoof kinetics and distal limb kinematics were collected from horses (n = 34) at trot. Dorsal hoof wall angle was used to classify horses as even or uneven (1.5° difference between forefeet respectively) and individual feet as flat (55°). Functional kinetic parameters were compared between even and uneven forefeet using MANOVA followed by ANOVA. The relative influences of differences in hoof angle between the forefeet and of absolute hoof angle on functional parameters were analysed using multiple regression analysis (P<0.05). In horses with uneven feet, the side with the flatter foot showed a significantly larger maximal horizontal braking and vertical ground reaction force, a larger vertical fetlock displacement and a suppler fetlock spring. The foot with a steeper hoof angle was linearly correlated with an earlier braking-propulsion transition. The conformational differences between both forefeet were more important for loading characteristics than the individual foot conformation of each individual horse. The differences in vertical force and braking force between uneven forefeet could imply either an asymmetrical loading pattern without a pathological component or a subclinical lameness as a result of a pathological development in the steeper foot

Inertial sensor-based system for lameness detection in trotting dogs with induced lameness

Lameness detection can be challenging in dogs, as reflected in the reported low inter-rater agreement when visually assessing lameness. The aim of this study was to use an inertial sensor-based system to detect and quantify induced distal and proximal limb disturbances mimicking supporting and swinging limb lameness in dogs trotting on a treadmill by measuring vertical head and pelvic movement symmetry. Ten clinically sound dogs were equipped with inertial measurement units that were attached to the head, pelvis and right distal forelimb. Vertical head and pelvic movement symmetry were measured while dogs trotted on a treadmill, before and after the induction of moderate support or swinging fore- and hindlimb lameness. Four symmetry variables were calculated: the differences in displacement between the two lowest and between the two highest values of the head and pelvis per stride, respectively. These variables were defined as minimum head difference (HDmin), maximum head difference (HDmax), minimum pelvic difference (PDmin) and maximum pelvic difference (PDmax)

Inertial sensor-based system for lameness detection in trotting dogs with induced lameness

Lameness detection can be challenging in dogs, as reflected in the reported low inter-rater agreement when visually assessing lameness. The aim of this study was to use an inertial sensor-based system to detect and quantify induced distal and proximal limb disturbances mimicking supporting and swinging limb lameness in dogs trotting on a treadmill by measuring vertical head and pelvic movement symmetry. Ten clinically sound dogs were equipped with inertial measurement units that were attached to the head, pelvis and right distal forelimb. Vertical head and pelvic movement symmetry were measured while dogs trotted on a treadmill, before and after the induction of moderate support or swinging fore- and hindlimb lameness. Four symmetry variables were calculated: the differences in displacement between the two lowest and between the two highest values of the head and pelvis per stride, respectively. These variables were defined as minimum head difference (HDmin), maximum head difference (HDmax), minimum pelvic difference (PDmin) and maximum pelvic difference (PDmax)

Vertical head and pelvic movement symmetry at the trot in dogs with induced supporting limb lameness

Compensatory limb loading has been studied in lame dogs; however, little is known about how these compensations relate to motion of the head and pelvis, assessment of which is an important component of lameness examinations. The aim of this study was to describe the patterns of vertical head and pelvic motion symmetry at the trot in dogs with induced supporting limb lameness in the forelimbs or hind limbs. Ten sound dogs were trotted on a treadmill before and after temporary induction of moderate lameness (grade 2/5) in each limb. Reflective markers were located on the head, pelvis and right forelimb, and kinematic data were captured with a motion capture system. Upper body symmetry parameters were calculated, including differences between the highest (HDmax) and lowest (HDmin) positions of the head, and between the highest (PDmax) and lowest (PDmin) positions of the mid-pelvis, with a value of zero indicating symmetry. The head was lowered more during the sound limb stance phase and lowered less during the lame limb stance phase in supporting forelimb lameness (HDmin: 4.6 mm in dogs when sound, −18.3 mm when left limb lameness was induced and 20.5 mm when right limb lameness was induced). The mid-pelvis was lowered more during the sound limb stance phase and lowered and lifted less during the lame limb stance phase in supporting hind limb lameness (PDmin: 1 mm in dogs when sound, −10.1 mm in left limb lameness and 8.4 mm in right limb lameness). The hip of the lame side, measured at the level of the greater trochanter, had an increased downwards displacement during the lame limb swing phase (−21 mm in left hind limb lameness, P = 0.005; 23.4 mm in right hind limb lameness, P = 0.007). Asymmetry in the lowering of the head or mid-pelvis is a more sensitive indicator of supporting forelimb and hind limb lameness, respectively, than asymmetry in the raising of the head. Increased displacement of the hip (‘hip drop’ of the lame side during its swing phase) is a good indicator of hind limb lameness in dogs

Validity and reliability properties of canine short-term heart rate variability measures-a pilot study

The objective of the pilot study was to compare validity and reliability properties of Polar RS800CX (Polar Electro Oy, Kempele, Finland) against simultaneously recorded electrocardiogram (ECG) measuring time- and frequency-based short-term heart rate variability (HRV) parameters, in dogs during stationary standing position. Five-minute recordings with less than 5% error rates from inter-beat interval (IBI) series obtained by Polar RS800CX and ECG, in 8 adult dogs, were used for HRV analysis. Polar data were statistically compared to the ECG data to assess for systematic differences in time- and frequency-based HRV parameters. Relative and absolute reliabilities were estimated by intraclass correlation coefficient, Spearman ρ, Bland and Altman analysis, standard error of measurement, and standard error of measurements in percentage. Paired t test was used to determine the statistical significance of differences between the measurement methods. Results: There were high correlation coefficients between HRV parameters obtained from Polar RS800CX and ECG. Intraclass correlation coefficients were 0.98-1.00, and Spearman ρ was 0.93-0.98. There were differences between the methods in 2 HRV parameters, the standard deviation of normal-to-normal IBIs (SDNN) (P = 0.035) and the square root of the mean squared differences of successive normal-to normal IBIs (RMSSD) (P = 0.034). Standard error of measurements was between 2.8-11.6% in ECG and between 2.6-11.8% in Polar, indicating rather high measurement error in 3 of the HRV parameters in both measurement methods. Close agreements and high correlation estimates in this pilot study indicated acceptable relative reliability in Polar RS800CX measuring time- and frequency-based HRV parameters in the group of dogs studied. However, the present pilot study revealed differences between Polar RS800CX and ECG in time-based standard deviation of normal-to-normal and square root of the mean squared differences of successive normal-to normal parameters, and that small amounts of erroneous IBI segments from Polar negatively impact on the validity and reliability properties of Polar RS800CX. © 2015 Elsevier Inc.Export Date: 23 September 2015</p