Page 49 - Canine Lameness

2.3 ­inematic Analysis 21

weight‐bearing” has gained interest in veterinary medicine with the use of a weight distribution
platform (WDP) or stance analyzer (Figure 2.1D). Static kinetics is not a new concept and can be
performed with more complex FP and PSW systems. However, dedicated WDP equipment
designed specifically to measure only standing weight‐bearing has entered the veterinary mar-
ket. This equipment is less expensive than complete kinetic systems and is a simple way to record
basic standing weight‐bearing measurements. It consists of a group of four pressure sensors that
are clustered together so that dogs can stand with each of their four paws on the individual pres -
sure sensors. Paw pressure is measured in real time and a computerized software displays the
%BWD in each limb.
Advantages of WDP systems are the ease of use and that minimal skill is required (Phelps et al.
2007). However, like any gait analysis tool, pitfalls during the collection process can affect the
results, such as distractions and head movement, abnormal limb position and posture, removing
or replacing paws during collection or restraint, and subjective acquisition of data only during
times of reduced or improved weight‐bearing. Unfortunately, research regarding these areas as
well as standardized and validated measurement protocols is lacking.
It is important to recognize that the role of standing weight‐bearing measurements in clinical
decision‐making is not well defined in dogs. The clinical relevance of limb off‐loading (e.g. lame-
ness) when standing as compared to moving is not fully understood. Currently, there is limited
published research regarding WDPs and there is only one recent peer‐reviewed publication com-
paring a WDP to a more well‐established kinetic system (PSW) in lame dogs (Clough et al. 2018).
That study demonstrated that a WDP was able to detect an objective lameness in a small and
widely varied population of dogs with various orthopedic conditions. However, the authors cau-
tion that the value of the WDP in dogs with more subtle or severe orthopedic disease is still
unknown. Additionally, they note that the value of a WDP in tracking the clinical progression of
orthopedic disease or therapeutic outcome has yet to be determined. For clinicians who desire to
use a WDP in clinical practice, it is important to recognize these current limitations in our under-
standing of WDPs. Where this equipment fits in clinical practice and more importantly how to
best utilize standing weight‐bearing measurements in patients with clinical disease are still being
explored.

2.3 Kinematic Analysis

Kinematic gait analysis is the study of motion and evaluates motion throughout the complete gait
cycle. Historically, joint angles have been most commonly evaluated and, in the past, this has been
limited to research facilities, universities, and large referral hospitals due to the expensive and
complex equipment. However, with computer and software advancement, this method of analysis
is now more widely available and affordable. This technology can vary greatly from simplistic and
inexpensive to the highly advanced and costly, respectively. With proper technique, any kinematic
systems can provide clinicians with valuable information to aid in the detection and treatment of
musculoskeletal pathologies.
Kinematic data collection in veterinary medicine is focused on evaluating motion in one of two
ways:

1) Motion occurring in a single plane (2D analysis)
2) Motion occurring in multiple planes (3D analysis)