Get access to all handy features included in the IVIS website
- Get unlimited access to books, proceedings and journals.
- Get access to a global catalogue of meetings, on-site and online courses, webinars and educational videos.
- Bookmark your favorite articles in My Library for future reading.
- Save future meetings and courses in My Calendar and My e-Learning.
- Ask authors questions and read what others have to say.
What Is the Difference between the Objective Gait Analysis Systems?
Pfau T.
Get access to all handy features included in the IVIS website
- Get unlimited access to books, proceedings and journals.
- Get access to a global catalogue of meetings, on-site and online courses, webinars and educational videos.
- Bookmark your favorite articles in My Library for future reading.
- Save future meetings and courses in My Calendar and My e-Learning.
- Ask authors questions and read what others have to say.
Read
Over the last two decades we have witnessed a revival of quantitative equine gait analysis systems. Miniaturisation of sensors, cost-effective electronics, stable wireless connections combined with the recent surge in automated pattern recognition (often referred to as artificial intelligence or AI) has catapulted gait analysis from the stage of ‘specialised research tool’ to widely used clinical decision-making aid [1]. The main application of the majority of systems marketed to veterinarians is of course the detection and quantification of movement asymmetry in the context of lameness. With increasing amounts of data from ‘normal horses’ [2,3] and horses undergoing clinical lameness examinations [4] now available, a debate has arisen about the associations between movement asymmetries (quantitative gait measures) and lameness (a clinical sign) [5- 8]. Irrespective of which side of the debate you are assigned to, it appears important to understand the fundamental principles of gait analysis tools when deciding whether or not to incorporate any of these tools into daily practice.
Generally, gait analysis tools can be categorised as kinetic (quantifying the forces and moments that are the sources of movement) or kinematic (quantifying the movements but ignoring the forces that have ‘created’ them).
Force platforms, force shoes, pressure mats or pressure ‘insoles’ are examples of kinetic devices. The advantage of these devices is that they can visualise what the eye of the observer cannot perceive: where and how the forces are acting between the ground and each hoof. Choosing one kinetic device over the other depends on factors such as cost (both are expensive, force plates more so through the limited number of time-synchronous footfalls (one!) that can be resolved), three-dimensional (force plates/shoes) vs. vertical information (pressure devices) or accuracy (force plates superior). For both options, collecting a sufficient number of strides under nonlaboratory conditions can be challenging; hence further efforts need to be concentrated on creating clinically applicable analysis tools.
Camera-based systems and many systems based on inertial measurement units (IMUs) are examples of kinematic systems. Typically, these require markers or sensors to be attached to the animal; however, recent progress in markerless tracking of movement [9] is an example of how pattern recognition provides progress in this area.
More traditional approaches, such as 3D optical motion capture with three or more cameras, have led to the development of horse-specific analysis software for clinical practice [10,11]. The advantage of these systems is their versatility, e.g. being able to easily modify the markers used and, for example, study joint angles etc. The price tag of such multicamera systems suitable for capturing a sufficiently large capture volume, i.e. the area in which the horse’s movements can be quantified, is still somewhat prohibitive for widespread use in ambulatory practice.
IMUs, likely helped by continued miniaturisation and cost- effective large-scale production, have become increasingly popular; most commonly to date, systems quantify vertical head and pelvic movement asymmetry making use of the known relationship between head (pelvic) movement asymmetry and force asymmetries in forelimb (hindlimb) lameness [12,13]. A simple approach of using the inbuilt IMUs of a smartphone has shown that pelvic movement asymmetries are associated with an individual clinician’s lameness score [14], enabling a clinician to establish their own individual’s movement asymmetry range for different lameness grades.
Adding withers movement asymmetry has been shown to be useful for differentiating between a head nod related to forelimb force asymmetries and a compensatory head nod in reaction to a hindlimb force asymmetry [15]. Research in this area has for example now ‘modelled’ force asymmetries from movement asymmetries [16] and investigated the effects of diagnostic analgesia (straight line and lunge) with ‘automated decision- making’ [17].
Other IMU-based systems combine measurement of limb movements with measurements of upper body movement [18] or aim at only measuring distal limb (hoof) motion [19,20]. Limb movements are particularly interesting in the context of additional lameness parameters such as increased/decreased cranial/caudal phases of the stride. Hoof movements have particular appeal for trimming/shoeing/remedial farriery. The opportunity to gather long-term data over several shoeing cycles may help with finding evidence-based strategies for prevention of specific orthopaedic issues.
In summary, there are many options for gathering kinetic and kinematic gait analysis data. In particular, kinematic IMU and camera-based approaches appear to be well suited for clinical applications, where ‘ease-of-use’ translates into the ability to collect a sufficient number of strides for evidence-based decision with confidence. Whatever system is being employed, attention should always be given to appropriately conducted validation studies in relation to the expected changes/differences of the intended use.
[...]
Get access to all handy features included in the IVIS website
- Get unlimited access to books, proceedings and journals.
- Get access to a global catalogue of meetings, on-site and online courses, webinars and educational videos.
- Bookmark your favorite articles in My Library for future reading.
- Save future meetings and courses in My Calendar and My e-Learning.
- Ask authors questions and read what others have to say.
About
Affiliation of the authors at the time of publication
University of Calgary, 2500 University Drive NW, Calgary, Alberta T2N 1N4, Canada
Comments (0)
Ask the author
0 comments