Practical Matters: How you can easily assess motor function and pain perception in nonambulatory animals

Jun 01, 2007

To help reach a prognosis in nonambulatory animals with spinal cord disease, assess voluntary motor function or pain perception.

If an animal is a nonambulatory paraparetic or a paraplegic (i.e. has normal function in the thoracic limbs and is nonambulatory in the pelvic limbs), one way to assess the voluntary motor function of the pelvic limbs is to support the animal's body weight with a hand under its pelvis. When the animal walks forward using its thoracic limbs, voluntary movements may be seen in the pelvic limbs. If there is minimal motor function, only hip flexion may be seen.

In a recumbent animal, touching the paws may elicit a reflex movement (withdrawal reflex), but this reflex does not necessarily mean that the animal has voluntary movement.

In animals lacking voluntary movements, assess pain perception. Evaluate superficial pain perception by pinching the toe web with a hemostat, and evaluate deep pain perception by pinching the toe (the periosteum). Again, withdrawing the limb is a withdrawal reflex; it does not mean the animal feels the pinch. A positive result in a pain perception test is the animal's showing a conscious response to the stimulus, such as trying to bite, whining, or ceasing to pant, or an increase in heart and respiration rates.

Helena Rylander, DVM, DACVIM (neurology)
Helena Rylander, DVM, DACVIM (neurology)
Department of Medical Sciences
School of Veterinary Medicine
University of Wisconsin
Madison, WI 53706