Front Matter

Chapter 2 Locomotion and Athletic Performance 37

resulting in gait changes (Rumph et al., 1997),
the need to standardize the velocity of the
subject, and the extreme variability in the mor-
phology of different breeds of dogs (Molsa
et  al., 2010). As with other systems, the time
required to acquire and analyze kinetic data
means that these systems are generally not
useful in a clinical context.

Kinematic analysis

Kinematics is the science of the motion of
objects, and kinematic gait analysis quantifies
the positions, velocities, acceleration/decelera-

tion, and angles of various anatomic structures

in space. Kinematic analysis can be performed

in two dimensions, which record data in the x

and y axes normal to the camera lens, or three

dimensions, which include data that are out‐of‐

plane to the lens, thus providing rotational and

circumduction data. Three‐dimensional (3‐D)

data are proportionately more accurate and

more complex to obtain and analyze. These

systems can be used to characterize normal gait

in dogs of various sizes and breeds, to analyze

lameness of any cause, and to monitor response

to surgical, medical, and rehabilitation therapy

(Lee et al., 2007; Off & Matis, 2010).

225

200

175

150

125

100

75

50

Pressure (Newtons)^25

0

–25

–50

0.45 0.50 0.55 0.60 0.65 0.70 0.75

Time (s)

0.80 0.85

Anterior/posterior forces

Lateral/medial forces

Vertical forces

0.90 0.95 1.00 1.05

Figure 2.16 Typical force plate report, showing the forces produced by the thoracic limb (first peak) and the pelvic
limb (second peak) in each of the three dimensions. Source: Adapted from Gillette & Angle, 2008.

(A) (B)

Figure 2.17 The typical kinematic analysis system uses colored, retroreflective, or light‐emitting diode (LED) markers
(A) that identify specific anatomic landmarks on the dog that are associated with the limb or joint under study. Distances
between any pairs of markers and angles between groups of three markers (B) are calculated by computer.