Hypothesis 3:  nerve damage as a result of trauma

We already know that the right tibia is fractured based on palpation; this hypothesis 
applies mainly to the left leg since the source of injury is unknown.

Nerve damage is a possible suspect because there is abnormal limb movement and 
inconsistent reflexes.  Reflexes are the result of spinal nerve stimulation.  The stimulus 
goes through an arc in the spinal cord without being sent to the brain immediately.  
Instead, the spinal motor neuron causes the muscle to move immediately as a result of the 
sensory stimulus.  Although there is no palpable pain in the spine, the dog is on so many 
potent painkillers that the pain response is probably impaired.  The dogÕs analgesic doses 
should be reevaluated before a complete neurologic exam is performed.  The nerve 
damage could be the direct result of trauma or subsequent compression due to the 
extensive swelling as a result of soft tissue trauma.  Compression would prevent the 
transmission of the nerve impulse.  To evaluate the possibility of nerve damage, the leg 
should be stimulated following the pattern of the sensory dermatomes.  Also, the 
abnormal limb movement should be further investigated to see if it is the result of pain or 
nerve damage.