Kinematic discrimination of ataxia in horses is facilitated by blindfolding

Abstract

Summary Background Agreement among experienced clinicians is poor when assessing the presence and severity of ataxia, especially when signs are mild. Consequently, objective gait measurements might be beneficial for assessment of horses with neurological diseases. Objectives To assess diagnostic criteria using motion capture to measure variability in spatial gait‐characteristics and swing duration derived from ataxic and non‐ataxic horses, and to assess if variability increases with blindfolding. Study design Cross‐sectional. Methods A total of 21 horses underwent measurements in a gait laboratory and live neurological grading by multiple raters. In the gait laboratory, the horses were made to walk across a runway surrounded by a 12‐camera motion capture system with a sample frequency of 240 Hz. They were made to walk normally and with a blindfold in at least three trials each. Displacements of reflective markers on head, fetlock, hoof, fourth lumbar vertebra, tuber coxae and sacrum derived from three to four consecutive strides were processed and descriptive statistics, receiver operator characteristics (ROC) to determine the diagnostic sensitivity, specificity and area under the curve (AUC), and correlation between median ataxia grade and gait parameters were determined. Results For horses with a median ataxia grade ≥2, coefficient of variation for the location of maximum vertical displacement of pelvic and thoracic distal limbs generated good diagnostic yield. The hoofs of the thoracic limbs yielded an AUC of 0.81 with 64% sensitivity and 90% specificity. Blindfolding exacerbated the variation for ataxic horses compared to non‐ataxic horses with the hoof marker having an AUC of 0.89 with 82% sensitivity and 90% specificity. Main limitations The low number of consecutive strides per horse obtained with motion capture could decrease diagnostic utility. Conclusions Motion capture can objectively aid the assessment of horses with ataxia. Furthermore, blindfolding increases variation in distal pelvic limb kinematics making it a useful clinical tool.

Outcomes after cervical vertebral interbody fusion using an interbody fusion device and polyaxial pedicle screw and rod construct in 10 horses (2015‐2019)

“…Furthermore, inability to detect small levels of improvement are inherent to the relatively crude and subjective assessment of ataxia using the modified Mayhew scale. Further development of objective tools of gait analysis to detect ataxia and minor differences remains an important area of development in equine neurology 36‐39 …”

A kinematic comparison of the locomotor pattern of horses sedated with detomidine alone and in combination with low doses of butorphanol

“…It is a sensitive parameter that can detect and quantify uncoordinated movements during walking. Regularity measures the stride to stride variability (which is also determined using other kinematic methods) as overground motion capture for differentiation between horses with and without ataxia [31]. In the current study, the administration of the combination of drugs induced a greater but not significant decrease in regularity values 5 min after the injection; however, from that moment onwards, all decreases in regularity were more pronounced in the detomidine group, with a longer duration of gait deficits (in the first 90 min) than the combination group (in the first 45 min) and with significant differences at 60 and 75 min.…”

Measurement of Canine Ataxic Gait Patterns Using Body-Worn Smartphone Sensor Data

“…There are well-established methods and models for data collection and interpretation within different pathologies in people ( 16 ), highlighting that instrumentation of gait using digital technologies provides objective and subtle information that is not possible to detect from clinical observation alone. For quadrupeds, objective assessment of ataxia gait patterns was studied in Olsen et al ( 17 ). It was found that motion capture can objectively aid the assessment of horses with ataxia; moreover, blindfolding of horses facilitates the discrimination of ataxic patterns.…”