Nucleoplasty is minimally invasive spine surgery using the true definition of the phrase. It is a purely percutaneous means by which a disc which has degenerated and prolapsed, causing radiculitis (or radiculopathy depending on the severity and duration of the condition) and discogenic back pain can be treated.
'Percutaneous' when you take it back to it's latin roots simply means 'by way of the skin'. This is a surgical procedure which is performed through a single needle using intra-operative x-rays to guide it. No incision is made and nothing needs to be sutured. Usually patients go home a few hours later. A general anaesthetic is usually required and is the safest way to perform this procedure but it can be done under pure sedation. The procedure takes about 15 minutes.
The needle is placed into the disc just at the junction of where the annulus becomes the nucleus (see page on disc anatomy and mechanics) and a special probe inserted through the needle. This probe has a slight curve on it which means that as it is pushed backwards and forward across the nucleus it can be rotated so that a different direction is taken each time. The probe uses radio-frequency bi-polar at high voltage and 120 Hz to convert the molecules of the nucleus into harmless hydrogen, oxygen, carbon dioxide and nitrogen. It has been proven scientifically that 2 passes of the probe can turn the pressure inside the disc to zero, but in surgical practice we try to get at least 8 passes of the probe. Rendering the pressure inside the disc to zero effectively releases the pressure on the nerve from the prolapsed disc. Converting the nuclear chemicals from noxious cytokines and inflammatory mediators to harmless elemental molecules effectively rids the disc of the chemicals which we know cause discogenic back pain.
To the right is a diagram illustrating the tip of the needle just penetrating the disc and the probe has been placed through the needle and has been advanced across the nucleus towards the front of the disc. Each pass of the probe in a slightly different direction takes about 10-15 seconds carefully creating a channel through the disc plasma-ising the chemicals and decompressing the disc.
Once the channels have been created, the needle is simply removed and a small dressing placed over the needle hole.
There are many studies published in the scientific literature regarding the success of nucleoplasty. In 2002, Sharpes and his colleagues reported that 79% of patients had very significant reduction in their pain scores at the 6-month and 12 month mark following the procedure in a study which looked at 49 nucleoplasties. In 2005 Alexandre looked at 1390 patients who undertook this procedure and reported a 78% success rate at 12 months - the average age of the patient was 40 years old. Mirzai looked at 52 patients all of whom had nucleoplasty. The average reduction in pain was 46% at 2 weeks and had dropped to 28% of pre-op levels at 12 months. 94% of his patients were able to stop all painkilling medications.
This procedure only really works well on discs that have a contained disc prolapse. If the disc prolapse has burst through the posterior longitudinal ligament and become extruded or sequestered then it will not work. It similarly is only good at reducing the back pain if the back pain is discogenic in its origin. If the back pain is due to facet joint arthritis or because of severely altered mechanics then it will not work. Therefore only very select conditions can be treated this way. Generally discs in the early stages of degeneration causing chemical radiculitis or radiculopathy from contained prolapses are superbly treated by nucleoplasty.
It is very important to realise that this treatment does not restore mechanical properties back to the spine. It does not take away the degenerate disc. Almost certainly if you have a nucleoplasty, the disc will continue to degenerate and may well cause mechanical back pain or facet joint arthritis in years to come - which may well require reconstructive surgery. This procedure would, therefore, never be carried out on a normal disc for that reason. The beauty of this procedure is that no bridges are burnt if it fails and if a success then surgery can be avoided for many years making it an ideal treatment for patients who cannot afford to take a significant time away from work or for patients who are waiting for a health insurance policy to become accessible.