Knee
Saphenous nerve block
The saphenous nerve, a sensory branch of the femoral nerve, is blocked with ultrasound-guided local anaesthesia for anteromedial knee pain not responding to standard treatments.
How it is performed
The saphenous nerve is a purely sensory branch of the femoral nerve and carries pain from the anteromedial aspect of the knee. Using ultrasound, it is identified in the adductor canal, in the thigh, and local anaesthetic is deposited there (possibly with corticosteroid). The block has both diagnostic value — confirming the origin of the pain — and therapeutic value, and can precede a more lasting treatment with pulsed radiofrequency. It does not cause loss of strength, because the nerve is not motor.
Who it is for
- Anteromedial knee pain persisting after conservative treatment
- Residual pain after knee replacement or knee surgery
- Need to precisely identify the source of pain
Recovery
Outpatient procedure: you can walk immediately, with a possible sensation of numbness on the inner side of the knee for a few hours.
Conditions treated in this area: knee osteoarthritis (gonarthrosis), persistent pain after knee replacement, chronic tendinopathies, refractory anteromedial pain.
Scientific evidence
A double-blind randomised study on treatment of the saphenous nerve with pulsed radiofrequency in medial compartment osteoarthritis documents a significant reduction in pain and improved function; the literature on sensory nerve blocks of the knee confirms the role of these techniques as a minimally invasive option in refractory pain.
References on PubMed
- Comparative evaluation of functional outcome and pain relief after pulsed radiofrequency of the saphenous nerve within and distal to the adductor canal in medial compartment knee osteoarthritis: A randomized double-blind trial
Jadon A, Shahi PK, et al. — J Anaesthesiol Clin Pharmacol, 2022 · PMID 38666163
- Cryoneurolysis to treat the pain and symptoms of knee osteoarthritis: a multicenter, randomized, double-blind, sham-controlled trial
Radnovich R, Scott D, et al. — Osteoarthritis Cartilage, 2017 · PMID 28336454
Published data describe average results in groups of patients and are not a prediction of an individual outcome. The indication for treatment must always be assessed during a consultation.
Risks, costs and opinions
The three questions patients ask most often before deciding, with clear answers.
What are the risks of saphenous nerve block?
It is an outpatient procedure performed with a thin needle under local anaesthesia and continuous ultrasound guidance, which makes it possible to see the needle, the target and the structures to avoid in real time. The most common issues are transient: pain or swelling for 24-48 hours, a small bruise. Joint infection is a rare event, prevented by sterile technique. In treatments with cortisone, facial flushing or a temporary rise in blood sugar may occur in diabetic patients. Personal risks and contraindications are assessed during the consultation.
How much does the saphenous nerve block cost?
The cost depends on the setting in which the procedure is performed: some treatments are available through the National Health Service or under agreement, others privately or through insurance. The quote is given clearly before scheduling the treatment, and includes the assessment, the procedure and the planned follow-up. During the consultation I tell you which pathway is available in your case: you do not have to decide before knowing the cost.
Does it really work? What patients and the literature say
The most frequent questions are "how long does the benefit last?" and "can I repeat it?". The answer depends on the diagnosis and the stage: some injections resolve the painful episode, others serve to open a window in which rehabilitation becomes effective. Experiences read in forums concern cases different from yours. During the consultation we review your imaging and I tell you frankly what to expect, how many sessions may be needed and when another approach is better.
Want to know if it is right for you?
At the first consultation we review your clinical history and previous imaging together.