Deep pain in the paraplegic dog: how to test it
4-year-old French Bulldog with paraplegia for 12 hours due to a suspected thoracolumbar disc extrusion. When the toes of the pelvic limbs are pinched, it withdraws the limb strongly.
How should you interpret and complete this examination?
chevron_right Show answer and explanation
A. Withdrawal is a spinal reflex: apply a strong stimulus with forceps to the digit bone and look for a conscious response (head turning, vocalising, attempting to bite)
Correct. Deep nociception requires the stimulus to reach the brain. Withdrawal only proves the segmental reflex arc is intact and can be present in dogs without deep pain.
B. Strong withdrawal confirms that deep pain is preserved and the prognosis is excellent
This is the classic mistake: in a T3-L3 lesion the withdrawal reflex is preserved or even increased despite no conscious sensation caudal to the lesion.
C. To assess deep pain it is enough to pinch the flank skin and watch the cutaneous trunci reflex
The cutaneous trunci reflex helps localise thoracolumbar lesions but does not assess deep nociception in the pelvic limbs, which is tested on the digits (and tail).
D. Give a high dose of opioid first so the examination is not painful
Heavy analgesia or sedation before testing can blunt the conscious response and produce a false negative. Test deep pain before analgesia where possible, or interpret it cautiously.
lightbulb Key takeaway
Deep pain is the most important prognostic factor in thoracolumbar disc herniation. Test it in both pelvic limbs (medial and lateral digits) and the tail, using forceps with increasing pressure, and record the result and time: the trend over the following hours guides surgical urgency.
Test yourself with 10 random questions
Neurology · 100 questions, a different test every time
Related questions
Updated: October 31, 2026 · Educational content for veterinary professionals. It does not replace current clinical guidelines or the judgement of the attending veterinarian.