This document discusses the role of radiofrequency ablation (RFA) in chronic pain management. It begins with an introduction to chronic pain and failed conservative treatments. It then covers the principles, history, techniques, applications, and procedures of RFA. Key points include that RFA is a minimally invasive method to selectively destroy targeted nerves using heat to interrupt pain transmission. It has been shown to effectively reduce pain in conditions like facet joint syndrome, discogenic pain, and osteoarthritis when more conservative methods fail. Precise patient selection, training, and a multidisciplinary approach are important to the successful use of RFA.

1. ROLE OF RADIOFREQUENCY ABLATION IN
CHRONIC PAIN MANAGEMENT
PRESENTER:DR KAUSTAV BASU THAKUR
MODERATOR: DR AKOIJAM JOY SINGH

2. INTRODUCTION
Chronic pain
 Continuum of therapies available
 Failed conservative management- interventions
INTERVENTIONS
DIAGNOSTIC THERAPEUTIC

3. INTRODUCTION CONTD
• Neurolysis – destruction of nerves
• Known for centuries
• Interrupt nociceptive pathways
• Long term control of pain
• Various methods available

4. RADIOFREQUENCY ABLATION
• Minimally invasive, target selective
• Reduces pain in several chronic conditions
• Produces temperature controlled target nerve destruction
(thermocoagulation)
• Reduces pain by pain transmission modulation

5. OBJECTIVE
Deposit enough RF power into tissue to raise the temperature
of the target tissue above 45-50°C

6. HISTORY
• 1920s- Cushing did series of experiments to show utility
of RF technique
• 1930s- Kirschner used high frequency lesions of
Gasserian ganglion for trigeminal neuralgia
• 1950s- Hunsperger & Wyss proposed high frequency
alternating current for 1st time
• 1950s- Cosman & Arnoff produced first commercially
available RF generator

7. HISTORY CONTD
• 1975- First application for spinal pain by Shealy
• 1980s- Sluijter developed percutaneous RF technique for
cervical, lumbar, thoracic & sacral discogenic pain
syndromes
• 1994- Sluijter developed pulsed RF mode

8. PRINCIPLE
A high frequency current of 500 kHz produced by the RF
generator on the neural tissue through a closed circuit
produces neurolysis of the target nerve

9. PHYSICS OF THERMOCOAGULATION
Basic RF circuit
 RF generator machine
 Active electrode
 Cables
 Ground pad

10. RF Generator RF Needle & Cable
Ground Pad

11. A Closed Circuit

12. High frequency , low energy
current
Builds electromagnetic field
between electrodes
Free charged ions move back
and forth to cause oscillation &
collision
Friction raises temperature in
the tissues
Sensed by the active tip of
electrode

14. ACTIVE ELECTRODE/CANNULA
• Available in 5,10,15 cm size lengths
• Reusable/disposable
• Exposed tip delivers RF current
• Variables of RF cannula
 Total length of cannula
 Length of exposed tip
 Sharpness
 Type of tip (curved/straight)

15. LESION
• Shape- an inverted cone
• Size and consistency depends on
1) Electrode tip configuration
2) Temperature
3) Local tissue characteristics
4) Rate of thermal equilibrium
5) Time

16. ADVANTAGES
• Minimally invasive
• Lesion size accurately controlled
• Accurate placement of cannula
• Lesions can be reproduced
• Recovery rapid
• Minimum morbidity & mortality

17. INDICATIONS
• Nociceptive pain
• Neuralgic pain
• Sympathetically mediated pain
• Cancer related pain
• Mixed pain syndromes
• Neuropathic pain

18. CONTRAINDICATIONS
ABSOLUTE
• Infection
• Coagulopathy
• Pregnancy
• Deafferentiation pain
• Failed diagnostic block
• Not a replacement to
surgery
RELATIVE
• Patients with Pacemaker
• Pain relief lasting less
than 3 months

19. PATIENT SELECTION CRITERIA
• Contraindications to be ruled out
• Any chronic pain condition considered
• Favourable response to diagnostic blocks with at least
50% pain relief
• Patient must have realistic expectations

20. MINIMAL STANDARDS AND
RECOMMENDATIONS
• Multidisciplinary patient selection
• Prior diagnostic block/blocks
• Informed consent
• Fluoroscopic guidance
• Standardized report
• Standardized patient follow up
• Accurate training of physicians

21. PATIENT PREPARATION
WARD
 STOP antiplatelet drugs 3-5 days before
 Routine blood tests
 Nil per oral if sedation planned
 Scheduled dose of antihypertensive, antidiabetics
confirmed
 IV access
 Peri-procedure IV antibiotics

22. PATIENT PREPARATION
PROCEDURE ROOM
 Basic monitoring available
 Resuscitation equipment & drugs
 Test mode checking of RF machine
 Appropriate cannula
 Radiation gears
 Ground pad applied
 Thermistor connection to RF machine

23. APPLICATIONS
• Facetogenic pain
• Chronic OA knee
• Discogenic pain
• DRG rhizotomy
• Sacroiliac joint pain
• Axial pain
• Trigeminal neuralgia
• Coccydynia

24. FACET JOINT SYNDROME
• Common but underdiagnosed component of LBP
• Not amenable to surgical intervention
• Difficult conservative management
• Steroids provide short term relief
• RF neurotomy has a long term success rate of 60-70% in
well selected patients

25. NERVE SUPPLY Z JOINT

26. Controlled comparative diagnostic blocks on two occasions
at least 2 weeks apart with two different duration LA drugs
to test concordant response is recommended by ASIPP &
ISIS to improve the outcome

27. FLUOROSCOPY GUIDED LUMBAR MEDIAL
BRANCH BLOCK & RF NEUROTOMY
• Position: Prone, head turned to one side
Pillow under belly to reduce lumbar lordosis
• Monitoring: BP, ECG, oxygen saturation
• IV access & sedation: not essential
• Sterility: like any other surgical procedure

28. C Arm:
 AP view considered
 Level of facet joint confirmed with
lateral view
 Squaring done
 C arm rotated to oblique view by
10-25° until grooves between SAP
and transverse process clearly
visible

30. PROCEDURE
• Skin overlying needle entry site infiltrated with 1-2%
lidocaine solution
• 22/23 G, 3.5 inch spinal needle entered
• End on view needle
• Bony contact confirmation done with AP and Lateral view
• 0.5 ml dye injected
• 0.5-0.75ml LA injected

31. TO BE REMEMBERED
• For one facet joint two adjoining level medial branches
are targeted
• For e.g. L4-5 facet is innervated by medial branch of L3
and L4 that are positioned over L4 and L5 transverse
processes

32. PROCEDURE
• RF cannula introduced and placed in
the groove
• Stylus removed and replaced by
thermistor probe
• Bare tip in contact with the desired
tissue
• Impedance on RF machine set at
200-600 ohm

33. • Sensory stimulation done at 50 Hz
• Confirmed by paraesthesia in the area
• Motor stimulation at 2Hz
• Confirmed by twitch in the multifidus
muscle
• Once position confirmed, 1 ml of LA
with or without steroid injected to
decrease discomfort
• Lesion carried out at 80°C for 90 secs

34. POST PROCEDURE INSTRUCTIONS
• Local Ice pack application
• Systemic analgesics for 3 days
• Counselled that effect takes around 10-14 days
• Pain relief for 6 months to 2 years
• Can be repeated if pain recurs

35. Genicular Nerve Block & RF Neurotomy of
Knee Joint
• INDICATIONS
 Chronic OA knee
 Failed knee replacement
 Unfit for knee replacement
 Unfit for surgery

36. ANATOMY

38. CONCLUSION
• Useful modality when conservative methods fail
• Minimally invasive, target selective, safe & efficacious
• Enough evidence supporting use in common pain
conditions
• Requires specialised training and thorough knowledge of
neural anatomy

39. TAKE HOME MESSAGE
Appropriate use of RFTC shows promise when used
responsibly in properly selected patients & in conjunction
with a multidisciplinary approach to the treatment of pain