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The Results

Results of Endoscopic and Other Surgery

Here we summarise the different surgeries that are possible.

Before starting, we would caution you against the over interpretation of small differences in success or failure rates with published data. There are many factors which can confound things:

  • New techniques tend to be studied by experienced experts on selected sub-groups of patients whereas published data on old techniques tend to be looking at how populations of surgeons get on when the method is applied to all comers.
  • Different populations of patients with different problems are included within the “slipped disc” population and so different sub-groups may be reported and the purported difference in outcome simply reflect a more responsive pathology being found in the differing sub-populations.
  • Drop out rates from the studies may vary and can corrupt the results favourably or unfavourably.
  • Length of follow-up may vary as can the threshold in symptoms taken to indicate “failure”. In general, the longer and harder you look the more recurrence you see.
  • Some techniques are surgically more challenging and thus a specialist centre does disproportionately better than does the general community spinal surgeons.

That said, the results available from the various international groups are reassuring that the technique is at least as good and as safe as other techniques – in the right hands.

There are three techniques to compare:

Keyhole Open Microdiscectomy: This is the established “gold standard” against which all other techniques need to be measured. It is the method used to remove herniated intervertebral discs in most centres and is performed with the help of an operating microscope. It involves entering the spinal canal between the lamina of the adjacent vertebra, identifying the nerve root and removing the herniated fragment of disc that is compressing it, plus any other loose fragments of disc. It is the standard technique available in most centres. In many cases, it will remain the preferred option. The average success rate is 87%.  (Open surgery not using microscopes requires very large incisions and excess muscle stripping. It is seldom used in specialist centres today).

Percutaneous Nucleotomy (+/- Endoscopy): This is basically an old technique whereby a tube is placed into the middle of the disc under X-ray control and the non-herniated part of the disc is sucked out in the hope that the herniated bit will get sucked back in too, i.e., you take out the good bit of the disc in the hope, rather tan the expectation, that the bad bit will get better too. The surgeons at LESS have never supported this approach – it removes often very healthy disc and usually leaves behind the prolapsed part. The application of endoscopic visualisation does not ameliorate this underlying flaw. Even the reports of its proponents show only a 75-85% success rate in a highly selected sub-group of cases favourable to this technique where the disc is only bulging but still contained within the capsule. If applied to most prolapses, the technique would be expected to fail. We are of the view that the reported results are optimistic in established disc herniation.

Endoscopic Transforaminal Discectomy: Where possible this is the technique favoured by LESS. It involves decompressing the nerve root by directly retrieving the herniated fragment from within the spinal canal just as with the “gold standard” open microdiscectomy method. The difference is that access is gained to the spinal canal via the natural foramen, (hole), in the side of the spinal canal with the minimum of muscle dissection. With specialist endoscopes, (TESSYS™ equipment) the results for the removal of a sequestered intervertebral disc prolapse document a success rate of more than 93% in 1-year and 2-year follow-up studies. In addition, for those patients who already have had failed surgery with another technique, the success rate remains at more than 85%.

Which one is best for You?

We would not recommend a percutaneous discectomy except in very unusual circumstances. When there is a small contained bulge of the disc causing leg pain then it is a reasonable option. However, the other techniques work just as well and this situation is in fact exceptionally rare. Most small, contained disc bulges are not associated with referred leg pain. Remember none of these techniques offer anything other than relief from leg pain – back pain is not treated by these techniques.

The choice is therefore between endoscopic transforaminal versus open interlaminar discectomy.

Our view is that unless there is a good reason to do an open operation, even with microsurgical techniques, the endoscopic method is preferable as the muscle dissection is less, no ligaments are removed and the recovery is quicker. However, it is a close run thing and in certain circumstances open microsurgery is in fact preferred.

If the disc is very hard or associated with bony swelling (osteophytes) or hardened ligaments, the endoscopic technique struggles. Likewise, if the prolapse lies to the side of the spine outside of the central canal, open techniques struggle.

For this reason, we feel it is important to offer both methods and will recommend which ever we feel is the most appropriate for you. Often there are pros and cons behind each one in which case we will place them before you.


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