Spinal Cord Stimulators in Neuropathic Pain

1. Spinal Cord Stimulators in Neuropathic Pain

2. Introduction • Chronic pain is very common • Immense physical, psychological, societal impact • Financial burden

3. Neuropathic pain • Damage or dysfunction of the nervous system • Typical symptoms - burning - shooting - allodynia - hyperalgesia

4. Case history (1) • MrX - Referred to the pain clinic • PC - Right arm pain • Hx PC - Day 1 post medical procedure - Tingling, weakness, numbness of right arm

5. Case history (1) • Investigations - MRI - Nerve conduction studies - Electromyography • Diagnosis - Brachial plexus injury • Conservative management strategy EMG

6. Case history (1) • Follow up at 6 weeks - Burning, painful to touch, skin discolouration • Diagnosis - Complex regional pain syndrome (CRPS) • Therapies in pain clinic - Neurogenic pain medications - Cervical sympathetic block

7. Case history (1) SCS inserted 2013

8. Case history (2) • Mr FF, 62 yrs - GP referral to pain clinic • PC - Back pain radiating to both legs • Hx PC - 20 year history of back pain - Physiotherapy/analgesia - Multiple surgical procedures

9. Case history (2) • Diagnosis - “Failed back surgery syndrome” • Therapies in pain clinic - Neurogenic pain medications - Epidural and facet joint injections - L5/S1 nerve root block

10. Case history (2) SCS inserted 2013

12. Management of chronic pain

13. Management of chronic pain

14. Management of chronic pain

15. Management of chronic pain

16. Neuromodulation • Therapeutic alteration of the nervous system • Electrical or pharmacological • Implanted devices

17. Gate control theory of pain

18. Gate control theory and spinal cord stimulators

19. History of spinal cords stimulators

20. Which patients might be suitable for a SCS? • Failed back surgery syndrome • CRPS • Peripheral neuropathy • Ischaemic limb pain • Angina

21. SCS electrodes

22. SCS electrodes

23. Components of the SCS

24. Phases of SCS implantation 1. Assessment phase - appropriate pathology - appropriate patient 2. Trial phase 3. Implantation phase

26. Where are the electrodes placed? • Upper extremity T1-T2 • Low back T8-T10 • Lower extremity T10-T12

28. Trial phase

29. What are the criteria for a successful trial? • 50%  pain • Area of parasthesia = area of pain • Parasthesia not unpleasant • Functional improvement

30. Complications of SCS • Additional revision of the device (23%) • Hardware malfunction (10%) • Infection (4.6%) • Complications during insertion

31. Some issues for patients….

32. NICE Guidelines

33. Case history (1) Complex regional pain syndrome4 months later • VAS scores 10  3 • Some restoration of hand function • Reduction in analgesic medication • Improved mood

34. Case history (2)Failed back surgery syndrome2 months later • VAS scores 10  2 • Improved mobility • Reduced analgesic medications • Improved mood

35. Conclusion • Neuropathic pain is common, some patients are refractory to standard therapies • Neuromodulation is an alternative method for treating severe, intractable pain • Excellent results can be achieved with selected patients

36. Thank You