BACK PAIN

1. BACK PAIN A Pain Specialist's Perspective BACK PAIN

2. DR J KURIAN MD MRCP FRCA FFPM CONSULTANT ANAESTHESIA AND PAIN MEDICINE INTERVENTIONAL PAIN MANAGEMENT

3. Background Neurosurgical ablative treatments for pain since 19th century but now infrequently used Ablation eclipsed by percutaneous injections or therapies that target central or peripheral pathways

4. Pain An unpleasant sensory and emotional experience which we primarily associate with tissue damage or describe in terms of such damage, or both

5. Pain Pathophysiology Nociceptive pain Neuropathic pain

6. Nociception The detection of tissue damage by specialized transducers connected to A-delta and C-fibers

7. Classification of Pain Nociception Proportionate to the stimulation of the nociceptor When acute Physiologic pain Serves a protective function Normal pain Pathologic when chronic

8. Classification of Pain:Neuropathic Pain Sustained by aberrant processes in PNS or CNS Disproportionate to the stimulation of nociceptor Serves no protective function Pathologic pain

9. Peripheral and Central Pathways for Pain Ascending Tracts Descending Tracts Cortex Thalamus Midbrain Pons Medulla Spinal Cord

10. Nociceptive Pain Neuropathic Pain PNS peripheral nervous system PNS Peripheral sensitization “Healthy” nociceptors Abnormal nociceptors CNS central nervous system CNS Central sensitization Normal transmission Central reorganization Physiologic state Pathologic state Pappagallo M. 2001.

11. Overview

12. Chronic Pain Syndrome End result of a variety of pathological and psychological mechanisms that may have included, at some stage tissue or nerve damage.

13. Pain Interventions Nerve blocks and injections should be seen as part of a process of education and rehabilitation, allowing an opportunity for mobilization and return to normal activity.

14. Nerve Blocks (1) Diagnostic: local anaesthetic only, to clarify mechanism or simulate effects of therapy Therapeutic: anaesthetise a site or pathway temporarily(local anaesthetic) or “permanently”(lytic agent, cryo, radiofrequency) or reduce inflammation (corticosteroids) A block may be diagnostic and therapeutic eg. Symapthetic block or trigger point injection

15. Nerve Blocks (1) Diagnostic: local anaesthetic only, to clarify mechanism or simulate effects of therapy Therapeutic: anaesthetise a site or pathway temporarily(local anaesthetic) or “permanently”(lytic agent, cryo, radiofrequency) or reduce inflammation (corticosteroids) A block may be diagnostic and therapeutic eg. Symapthetic block or trigger point injection

16. Nerve Blocks (II) Common blocks for chronic pain include -Trigger-point injection -Bier block -Peripheral nerve injection (eg. Ilioinguinal,lateral femoral cutaenous, greater occipital) -Epidural injection -Intra-articular(eg.facet, SI joint) Sympathetic block(cervical, lumbar) Plexus block (coeliac, hypogastric)

17. Nerve Blocks (III) Case reports, preclinical data support long lasting effects of local anaesthetic blockade - RCTs support lytic coeliac block However, unclear how much clinical improvement reflects placebo effects, irrevelant cues, systematic absorption of local anaesthetic, expectations Side effects possible Rarely successful as a stand alone strategy for chronic pain

18. Trigger Point Injection Myofascial pain syndrome Taut band palpable (if muscle is accessible) Exquisite spot tenderness of a nodule in a taut band Pressure on tender nodule reproduces pain Range of motion with stretch limited by pain Techniques Dry needling Local anaesthetic only Local anaesthetic and steroid Botulinum toxin

19. Epidural Injection (I) Employed for decades using various techniques materials and patients Limited RCT evidence of efficacy Cervical, Thoracic, Lumbar , Caudal Trans laminar Transforaminal

20. Epidural Injection(II) Applied for symptomatic relief in Disc protrusion with radiculopathy Spinal stenosis(circumferential or transforaminal) Acute pain, local inflammation of vertebral fracture Acute herpes Zoster May facilitate rehabilitation, avert surgery when applied within multidisciplinary frame work

22. Steroid Injections • Interlaminar Epidural

25. Nerve Root Injection Diagnostic Establish or confirm mechanism of pain Therapeutic Local anaesthetic plus corticosteroid Technique Fluroscopy or CTessential for needle placement with contrast confirmation

31. INTRA ARTICULAR INJECTIONS Facet and Sacroiliac joints most common Diagnostic facet syndrome or SI joint pain Simulate results of potential spinal fusion or denervation of medial branch of dorsal ramus Therapeutic (local anaesthetic + corticosteroid) Reduce inflammation, pain Increase mobility, facilitate rehabilitation

32. Specific anatomic syndromes Facet syndrome Continuous pain worsened by rotation and extension Radiation into the leg or gluteal area, in a non-dermatomal distribution Tenderness over the joints and paravertebral muscle spasm

36. Sacroiliac joint injection

37. Symapthetic Blocks Diagnostic Stellate ganglion Lumbar Therapeutic CRPS of upper and lower extremity Vascular insufficiency Refractory angina Technique Local anaesthetic, Neurolytic

38. MISCELLANEOUS Trigeminal ganglion Glossopharyngeal nerve Sphenopalatine ganglion

41. NEWER DEVELOPMENTS PULSED RADIOFREQUENCY VERTEBROPLASTY IDET, DISCTRODE DORSAL COLUMN STIMULATORS PERIPHERAL NERVE STIMULATORS DEEP BRAIN STIMULATORS IMPLANTABLE PUMPS

45. Managing Pain

46. CONCLUSION Interventional approaches are often reserved for patients with well established problems, failure of other treatments and pronounced disability. Do we miss an opportunity for early cost effective preventive treatment by reserving interventions for those least likely to benefit? “Doctors think a lot of patients are cured who have simply quit in disgust” DON HEROLD 1889