Pain Management Procedures
Cluneal Nerve Block and RFA
Cluneal Nerve Block and Radiofrequency Ablation
What is it?
The cluneal nerves are small sensory nerves that cross the back of the pelvis and supply skin over the upper buttock. Entrapment or irritation can cause focal pain near the top of the iliac crest that may spread into the buttock and mimic sacroiliac or lumbar pain. A block places local anesthetic near the suspected nerve. RFA may be considered after a strongly positive diagnostic block.
When may it be recommended?
The procedure may be considered when examination finds a very specific tender point over the iliac crest and pressure reproduces the usual pain. Lumbar nerve-root pain, hip disease, SI-joint pain, and other common causes should be evaluated first.
What happens?
You lie face down. Ultrasound or fluoroscopy identifies the iliac crest and target area. A fine needle is guided near the cluneal nerve and local anesthetic, sometimes with steroid, is injected. If the block produces clear temporary relief, RFA uses a specialized needle to create a small controlled lesion that reduces pain signaling.
What should I expect?
Part of the upper buttock may feel numb. A diagnostic block wears off within hours, while steroid or RFA benefit may last longer. RFA soreness or a temporary burning sensation can occur before relief develops.
Important risks
Risks include bleeding, infection, medication reaction, temporary numbness, increased nerve pain, skin sensitivity, and uncommon nerve injury. Evidence for cluneal nerve RFA is less extensive than for lumbar facet RFA, so expectations and insurance coverage should be discussed.
Preparing for your injection procedure…
Your instructions will depend on the procedure. Before any injection, tell the APG team if you:
Take aspirin, warfarin, clopidogrel, apixaban, rivaroxaban, or another medicine or supplement that affects bleeding. Never stop a prescribed blood thinner unless the clinician who manages it and the procedure team tell you how to do so safely.
Have diabetes, glaucoma, a bleeding disorder, an active infection, fever, or recent antibiotic treatment.
Could be pregnant, have an allergy to contrast dye or local anesthetic, or have reacted to steroid injections before.
Use an implanted pacemaker, defibrillator, spinal cord stimulator, or other electrical device.
Some procedures require fasting, a medication adjustment, or a responsible adult to drive you home, especially when sedation is planned. Follow the instructions provided for your specific appointment.
After your injection procedure…
Most injections are outpatient procedures. Mild soreness, bruising, temporary numbness, or a brief increase in the usual pain can occur. Follow the activity and bandage instructions you receive. Steroid medicine may take several days to have an effect and can temporarily raise blood sugar.
Call the office promptly for increasing redness, drainage, fever, severe or rapidly worsening pain, or new numbness or weakness. Seek emergency care for trouble breathing, chest pain, sudden loss of bladder or bowel control, a severe new headache, loss of vision, stroke-like symptoms, or rapidly progressing weakness.
This information is for general education and does not replace medical advice, diagnosis, or treatment. Not every procedure is appropriate for every patient, and results vary. Your APG care team will review your symptoms, examination, imaging, medical history, medications, and prior treatment before recommending a plan. Coverage requirements also vary by insurance plan.