What is a Genicular Nerve Block?

A Genicular Nerve Block is a minimally invasive procedure used to treat chronic knee pain
by targeting the small sensory nerves around the knee joint, known as the genicular nerves. These nerves transmit pain signals from the knee to the brain. By injecting local anaesthetic, sometimes with steroid, near these nerves, the procedure helps to relieve pain and assess
whether longer-term treatments such as radiofrequency denervation may be suitable.

What conditions do we offer this for?

We may offer this procedure for patients with:

  • Chronic knee pain due to knee osteoarthritis
  • Persistent pain after knee replacement surgery
  • Patients unsuitable for or declining further surgery
  • For diagnostic purposes to assess suitability for radiofrequency treatment

Why is it done?

A genicular nerve block is performed to:

  • Provide temporary pain relief from chronic knee conditions
  • Help confirm whether the genicular nerves are the main source of pain
  • Support decisions about further treatment, including radiofrequency denervation
  • Reduce the need for oral pain medications
  • Improve mobility and quality of life

What does the procedure involve?

  • You will lie on your back with your knee supported.
  • The skin is cleaned and numbed with local anaesthetic.
  • Using ultrasound or X-ray guidance, fine needles are positioned near the target genicular nerves.
  • A small volume of local anaesthetic, with or without steroid, is injected.
  • The procedure usually takes 15–30 minutes and is done as a day case.

Benefits

  • Quick, targeted pain relief for the knee joint
  • Useful for diagnostic evaluation before further treatments
  • May reduce reliance on oral medications
  • Improved function, walking ability, and physiotherapy engagement
  • Can guide suitability for radiofrequency denervation

Side Effects

Very Common side effects

(may affect more than 1in 10 patients):
  • Pain or bruising at the injection site
  • Mild temporary numbness or stiffness in the neck
  • Temporary increase in pain before improvement

Common side effects

(may affect up to 1in 10 patients):
  • Localised swelling or discomfort
  • Light-headedness or dizziness

Uncommon side effects

(may affect up to 1 in 1,00 patients):
  • Infection at the injection site
  • Temporary leg weakness or unsteadiness

 Rare side effects

(may affect up to 1 in 1,000 patients):
  • Nerve injury or prolonged numbness
  • Bleeding or haematoma
  • Allergic reaction to anaesthetic or steroid

Aftercare Advice

  • You will be monitored briefly and can usually go home the same day.
  • Avoid driving for 24 hours.
  • Mild soreness or numbness may last for a few hours to days.
  • Use ice packs and simple painkillers if needed.
  • Gradually resume walking and activities as comfort allows.
  • A follow-up appointment may be arranged to discuss your response and next steps
    (e.g. radiofrequency treatment).

When to Seek Medical Attention

Please attend A&E immediately if you experience:
• Fever, chills, or signs of infection at the injection site
• Sudden chest pain, breathlessness, or dry cough
• New or worsening arm numbness or weakness
• Loss of bladder or bowel control
• Severe or ongoing neck pain not relieved by usual medication