It’s a diagnosis you’ve never heard of – but by some estimates, cluneal nerve irritation is responsible for up to 12% of all cases of lower back pain. With the medical community just starting to become aware of this condition, we asked internationally renowned spinal surgeon Mr Martin Knight describes what the cluneal nerves are, how they can become irritated, and whether there is any effective treatment.
What are the cluneal nerves?
The cluneal nerves form part of a complex group of nerves which run from your lower spine into the buttocks. In contrast to the well-known sciatic nerve – the thickest nerve in the body – the cluneal nerves are small branches of nerves. After these branches have left the spine, they join together and and become irritated as they cross the rim of the pelvis through tunnels in the muscles, ligaments or tissues.
Pain coming from the cluneal nerves can often be misdiagnosed as something else. For example, the “medial” group of cluneal nerves is located close to the sacro-iliac joint and can be mistaken for sacro-iliac joint pain. The pain is found beside the spine and buttock but can affect the groin, knee and foot, where it is easily confused with sciatica. If the pain affects the outer buttock, it might be misdiagnosed as trochanteric bursitis.
As a result, the treatment of the sacro-iliac joint, facet joints or trochanteric bursa – by steroid injection or radiofrequency ablation – is ineffective because it fails to tackle the real cause of the problem.
What causes cluneal nerve irritation?
Cluneal nerve irritation is usually caused by incorrect tilting of the pelvis from its original position and “kinking” of the nerves as they pass through their tissue tunnels.
This can be the result of structural problems, such as spinal stenosis, failed back surgery, or slipped disc. However, it can also simply be due to your posture – which might have been affected by past surgery, trauma, child birth or obesity.
The good news is that if you can fix this posture, you can “untrap” the nerve and significantly reduce the pain.
What does treatment involve?
Treatment starts with establishing to what extent the cluneal nerve is the cause of your back pain. This involves injecting the cluneal nerve leash with steroids and local anaesthetic. If the cluneal nerve is irritated, this injection should provide immediate pain relief. If a significant portion of the pain remains, we may need to look elsewhere for the cause.
Assuming cluneal nerve irritation is the cause, we next look at improving your posture through physiotherapy or a specialised form of pilates. In most cases, this should be enough to improve the symptoms.
However, if non-invasive treatments have failed to tackle the pain, some patients may benefit from radiofrequency ablation. This targets the sheaths of nerves that are trapped and can be highly effective. Patients who have had this treatment report improved symptoms more than four years after treatment, and find that their mobility has been significantly restored.