A Painfully Painful Primer On Pain “TO THE PAIN!” A Painfully Painful Primer On Pain

The Autobiography of Pain Origin of “pain” Poine Ancient cultures believed pain and disease were punishment Ancient practices  modern practices Medieval times were big on drugs

The Autobiography of Pain Coca-cola was sold as a “cure” for everything Contained cocaine Surgery techniques were bizarre British royalty popularized childbirth relief First significant tx in 1846 Use of anesthesia in surgery

Pain is Ubiquitous 50 million Americans has persistent pain 1/3 lose > 20 hrs sleep 2nd leading cause work absenteeism $100 billion cost High correlation between pain and depression

What Is Pain? “An unpleasant sensory and emotional experience associated with actual or potential tissue damage, or described in terms of such damage” (International Assoc for the Study of Pain) Nociception Encompasses all aspects of an individual Psychological, physical, emotional, physiology

First and Second Pain

Pain Has Different States Neuropathic pain Central sensitization Two main pathological pain states Hyperalgesia Allodynia Somatic sensation Affective perception

Pain is Painful 2 types: mechanical and polymodal Different signaling molecules Different molecules enhance response Principles of Neural Science

Pain Anatomy-Spinal Cord

Pain Anatomy-Spinal Cord Dorsal root and rootlets Spinal (dorsal root) ganglion Ventral root and rootlets Spinal nerve Dorsal ramus Ventral ramus Netter 169

Pain Anatomy-Brain Stem

Brainstem Nuclei PONS-MEDULLA JUNCTION UPPER PONS RVM LC PAG MIDBRAIN X RVM X LC PAG MIDBRAIN

Brainstem Inhibition of Pain 1st Order Noc. Neuron Inhibitory IN Spinothalamic Tract 2nd Order Noc. Neuron RVM (Opioids) RVM (Glutamate) RVM (5HT) LC (NE)

Brainstem Facilitation of Pain 1st Order Noc. Neuron Inhibitory IN Spinothalamic Tract 2nd Order Noc. Neuron RVM (Glutamate) RVM (5HT)

Gate Control Theory of Pain

TREATMENT Pharmacology TENS units Surgery

CONCLUSIONS Prevalent Not well understood Encompasses every aspect $$$$$$$ Treatment options limited