diagnostic medial branch block for low back pain

A diagnostic medial branch block is a targeted injection of local anaesthetic to temporarily numb the medial branch nerves, which carry nociceptive signals from the spinal facet joints (1,2):

Clinical Purpose:

• purely diagnostic tool confirms or rules out facet-mediated arthritic or mechanical axial back pain

Patient Selection:

• considered for localised axial pain after failing conservative therapies like physiotherapy

Next Steps:

• significant short-term relief (typically >80%) confirms the diagnosis, predicting successful long-term management via radiofrequency neurotomy/ablation

Reference:

1. Cohen SP et al. Consensus practice guidelines on interventions for lumbar facet joint pain from a multispecialty, international working group. Reg Anesth Pain Med. 2020;45(6):424–467.
2. Strand NH, Mintz DN, Vora MU. Medial branch blocks and radiofrequency ablation for low back pain. N Engl J Med. 2023;389(25):e55.