Jogging may be initiated when weightbearing improves and there is decreasing lameness at a walk. Initially, patients may jog
for 30 to 60 seconds two to four times a day. The amount of jogging may be increased 10% to 15% per week as long as lameness
does not worsen.
Stepping over rails
Stepping over cavaletti rails and walking in snow, sand, or tall grass increase active range of motion, strengthen muscles,
and improve endurance (Figure 5). Cavaletti rails are horizontal poles that are raised off the ground. The orientation, height, and speed of the course can
be modified to suit a patient's needs.
Figure 5. Cavaletti rails help improve active range of motion of all joints as a dog negotiates the obstacles. Stride patterns
can be altered by placing the rails closer or farther apart.
Pulling or carrying weights
To enhance muscle strength, you can fit patients with a harness to pull weighted sleds to increase power and muscle tone.
The amount of weight will vary depending on the animal's size and the design of the sled and harness. Initially, use only
light weights. The animal's gait should change only slightly so that the sled is easily pulled over the desired distance.
Heavier weights can be added after technique, strength, and endurance have been mastered with lighter weights. Similarly,
strap-on weights may be placed on the affected limb to improve muscle strength and stamina. Weights are generally used two
or three times a week. Again, it is important that the tissues subjected to increased forces be at the later stages of tissue
healing, and patients should experience no pain or lameness after exercise.
Aquatic exercise has many therapeutic benefits in people, and similar benefits have been demonstrated in small-animal orthopedic
and neurologic patients (Figure 6).36-39 Buoyancy, hydrostatic pressure, viscosity, resistance, and surface tension are all important physical properties of water
to consider when designing an aquatic rehabilitation program; each of these offers specific benefits.40 Buoyancy decreases the amount of weight placed on arthritic joints.41,42 Hydrostatic pressure provides constant pressure to a body or limb submerged in water at a given depth and increases as the
depth of the water increases. This pressure may aid venous and lymphatic drainage from an edematous distal limb or swollen
joint.41,42 Hydrostatic pressure may also decrease pain by providing a phasic stimulus to the sensory receptors to decrease pain perception.
The viscosity of water provides resistance to movement. This resistance may help strengthen muscles and promote cardiovascular
fitness. Viscosity may also increase the patient's proprioception underwater and help prevent falling by allowing more time
for a patient to correct an error in balance.42
Figure 6. This patient demonstrates increased active flexion of the elbow and carpus while walking on an underwater treadmill.
Surface tension becomes an important factor to overcome if motion occurs at the surface of the water. A joint undergoes increased
motion and work to break through the water's surface. In general, activities or motions that occur below or above the surface
are easier than those occurring at the surface.32,43 The degree of resistance and buoyancy can be adjusted by changing the water depth. Surface tension is constant regardless
of water depth but can be manipulated by changing the water level to the level of specific joints. Joint motion is altered
as the height of the water changes because of the force necessary to break through the surface.