Explaining Pain

1. Explaining Pain Dr. Erik Pohlman, PT, DPT

2. Pain is a common problem! • 1 in 6 Americans live with persistent pain1 • Globally, 20% have pain > 3 months2 • Persistent pain costs ~$100 billion/yr3

3. Definition of Pain • Pain is an “unpleasant sensory and emotional experience associated with actual or potential tissue damage.”4

4. Old Model • Painful stimulus→PAIN • Tissue damage = pain

5. How do we explain… • Phantom limb pain • even in those born without the limb5 • Painless battle wounds • Papercut hurting so much

6. Other Examples • WWII vet – bullet in neck 60 years, he never knew!6 • Surfers – feel a ‘bump,’ no more leg!

7. These patients had no pain, weakness, or sensation changes!7

9. Will this hurt?

10. How about now? Why?

11. Threat • Initially, the body only had to worry about the nail • Nail→Threat→PAIN • When you are running from the lion, the nail is the least of your worries • Nail→Lion is bigger threat→Nail doesn’t hurt • Explains soldiers in battle

12. Threat • It is the perception of the threat that determines the output, not the tissue damage itself or threat to the tissues…8Pain = Output

13. So how does pain really work?

14. Nociceptors (“Pain sensors”) • Mechanical, Temperature, and Chemical • They tell the brain ‘danger’, NOT ‘pain’ • Brain determines if you should feel pain • Body can add or subtract all over the body • Replaced as often as every few days • Current levels of sensitivity can and will change!

15. Sensitization • Increased sensitivity after injury • Allodynia, hyperalgesia • Normal, but should fade after healing • Persists in people with chronic pain

16. Central Sensitization2 • The spinal cord and brain cells are more sensitive • You may notice: • Pain longer than normal tissue healing time • Spreading pain • Worsening pain • Even small movements hurt • Pain is unpredictable (what hurts one day may not hurt the next, or thinking about it can cause pain) • You have other significant ‘threats’ in your life

17. Homuncu-what?

18. Homunculus • Map of body in the brain • Phantom limb • ‘Smudging’ in chronic pain and phantom pain • More chronic -> more smudging9

19. Neuroplasticity • Not to worry! • The brain and nervous system are constantly changing • Braille users10 and guitarists/violinists/cellists11

20. Brain Centers • Not just 1 center or one input (like from the tissues) • Neurotag – many parts of the brain activating in a unique pattern2 • Sensory, motor, memory, emotion, autonomic nervous system, etc. • All parts light up in phantom pain Danger signal, on its own, is NOT enough to produce pain!

21. Pain relies on context • Perception of threat level modifies pain according to the situation • Finger injury in professional violinist vs. dancer12 • Whiplash from car accident

22. Thought Viruses • Thoughts are nerve signals too • Ever feel pain when thinking about the painful movement or watching someone else do it? • Anxiety about pain or disability can increase pain

23. What does this tell us? • Pain comes from the brain, not muscle, tendon, disc, etc and… • HURT ≠ HARM

24. How can we fix our pain?

25. Bed rest? • NO WAY!!! • Blood flow leads to healing and less pain • Re-define that ‘fuzzy’ section in brain • Prevent atrophy

26. Surgery • Last resort, or when rapidly progressing neuro symptoms • Costly • Risky • Infection, nerve damage, • Still have a recovery period • May still not help • Plenty of people who still have their pain after surgery

27. Medication • Pain killers, anti-inflammatories, muscle relaxers, etc. • May or may not help symptoms • Often won’t help the actual cause

28. You are already well on your way! • Pain education • Patients can understand pain theories13 • Knowing pain physiology reduces threat level14 • …reducing sympathetic, endocrine, and motor activity.15,16 • Combining pain physiology education and movement therapies improves physical capacity, reduces pain, and improves quality of life!17 • Evidence shows that pain education may even be better at preventing pain than core stabilization18

29. Caution! • Don’t get hung up on anatomy! • Knowing more about pain leads to better results than knowing more about anatomy (bones, discs, alignment, etc)14 • You have now learned that is one (possible) part in the pain experience

30. Tone down that nervous system • Active Relaxation • Deep breathing • Breathing with diaphragm • Heat, ice, TENS, anything else that works for you

31. Graded exposure • Gradually increasing exercise, activity, and stimulation (desensitization) • Re-teaches body/brain that movements and stimulation are ok • Can also gradually re-expose yourself to driving or the thing you were doing when originally injured

32. Trick your nervous system • Same movement, different context • Do the movement in a different way • Change the position or what moves first, do in water, etc.

33. See your friendly local physical therapist to… • Rule out more serious issues and refer you to the proper provider if one is found • Determine if there is a mechanical cause • Provide more pain education • Provide treatments like manipulation, dry needling, therapeutic movement/exercise, etc.

34. Points to remember • Your pain is REAL • Imaging (Xray, MRI) may be misleading • Bedrest and waiting for it to improve will likely not help and may make it worse • Motion is Lotion • Pain is normal and it’s ok to feel some pain with exercise if you have chronic pain already • HURT ≠ HARM • See your physical therapist!!!

35. (Strongly) Recommended Reading Explain Pain, by David Butler

36. Thank you!

37. References • 1. Chronic Pain elective, Regis University 2011, quoted this as coming from the ‘American Chronic Pain Association.’ • 2. Butler D, Moseley GL. Explain Pain. Adelaide: NOI Group Publishing, 2003. • 3. Chronic Pain elective, Regis University 2011, quoted this as coming from the ‘American Alliance of Cancer Pain Initiatives.’ • 4. www.iasp-pain.org • 5. Saadah ES, Melzack R. Phantom limb experiences in congenital limb deficient adults. Cortex. 1994;30(3):479-485. • 6. The Times, Feb 17 2003, p 5, London. • 7. Boden SD, et al. Abnormal magnetic-resonance scans of the lumbar spine in asymptomatic subjects. J Bone Joint Surg Am. 1990;72a(3):403-408. • 8. Moseley GL. Reconceptualising pain according to modern pain science. Phys Ther Reviews. 2007;12:169-178. • 9. Flor H, et al. Extensive reorganisation of primary somatosensory cortex in chronic back pain patients. Neurosci Letters. 1997;244:5-8. • 10. Pascual-Leone A, Torres F. Plasticity of the sensorimotor cortex representation of the reading finger of braille readers. Brain. 1993;116:39-52. • 11. Elbert TC, et al. Increased cortical representation of the fingers of the left hand in string players. Science. 1995;270:305-307. • 12. Moseley GL. Joining forces- combining cognition-targeted motor control training with group or individual pain physiology education: a successful treatment for chronic low back pain. J Man Manip Ther. 2003;11:88-94. • 13. Moseley GL. Unravelling the barriers to reconceptualisation of the problem in chronic pain: the actual and perceived ability of patients and health professionals to understand neurophysiology. J Pain. 2003;4:184-189. • 14. Moseley GL, Hodges PW, Nicholas MK. A randomized controlled trial of intensive neurophysiology education in chronic low back pain. Clin J Pain. 2003;20(5):324-330. • 15. Melzack R. Pain and stress: a new perspective in psychosocial factors in pain. RJ Gatchel and DC Turk. 1999, Guildford Press: New York. • 16. Moseley GL. Evidence for a direct relationship between cognitive and physical change during an education intervention in people with chronic low back pain. Euro J Pain. 2004;8:39-45. • 17. Moseley GL. Physiotherapy is effective for chronic low back pain: a randomised controlled trial. Aus J Physioth. 2002;48:297-302. • 18. George SZ, Wittmer VT, Fillingim RB, Robinson ME. Comparison of graded exercise and graded exposure clinical outcomes for patients with chronic low back pain. JOSPT. 2010;40(11).