The Treatment of Disc-Related Back Pain
Contained and Non-contained disc protrusions.
It helps to understand the difference, illustrated below. If the disc annulus is damaged (allowing the nucleus protrude into it and the overall outline of the disc to bulge) but not torn through and through, it is called a contained protrusion. If the annulus is torn open and disc nucleus is extruded into the spinal canal it is called an extrusion.
Extruded disc nucleus should be removed by open surgery or endoscopic discectomy.
Contained disc protrusions/bulges and Internal Disc derangement can be treated by the methods described here.
Minimally invasive Treatment of Painful Intervertebral Discs
The standard of care for patients disabled by spinal pain from a intervertebral disc is spinal fusion or, in selected cases, disc replacement surgery. While these remain the correct and only treatments in certain situations these are very major undertakings and most patients with disc related pain would prefer something less invasive if it were available.
Over the years, several minimally invasive techniques and technologies for treating painful discs have been introduced. These are based on an understanding of how pain arises in discs and are all deployed by needles or small catheters around 2-3mm diameter. While a small skin incision is needed, no open dissection is required to gain access to deeply placed tissue in the spine and the electrode needles used are often not much bigger than a standard blood test needle so these techniques are as minimally invasive as possible.
Percutaneous Decompression by coblation “Nucleoplasty”:
The coblation (cold ablation) catheter (Arthrocare) is simple to use and very safe. It uses electrical radiofrequency energy to vaporise tissue with which it is physically in contact and so provides a very targeted means of removing tissue. Surgeons in numerous disciplines have been using this technology for years and I have used it in the spine over at least 8 years. There is a reasonable video on this website
By using this in the disc nucleus, one can reduce a small volume of the nucleus material, rapidly reducing pressure and also inducing a variety of anti-inflammatory changes. It is recommended by the manufacturer (Arthrocare) for reducing small (contained) slipped discs, and it is effective for this indication, but it also seems effective in stopping back pain from damaged discs without sciatica. In my hands amongst a small number (40 or so) of highly selected cases, I have had around 65% success (excellent [>75% relief] or very good [>50% relief]) in the treatment of pure disc related backache. Relief, once obtained seems to be durable and I have rarely had to retreat the same disc. Sciatica due to smaller contained disc prolapse can also be treated and there is an adapted instrument for the same treatment in the neck, studied and reported on by Prof Cesaroni, Rome from whom I learned the technique.
Mini-microdiscectomy by Disc FX (Elliquence, NY)
This is a very new, innovative and potentially very powerful minimally invasive system with considerable scope for the treatment of more significant disc derangements causing both back pain and sciatica. I had the privilege to be the first user of this technology in the UK. Reported outcomes and safety over 4 years are in the 70% success range, maintained but experience is limited and so enthusiasm has to be tempered with appropriate caution at this time. My own results are in line with this experience.
This miniature system (3mm diameter introducer) allows the possibility of combining the major modalities of treatment (physical removal, RF tissue ablation, annular heat denervation) along with endoscopic visualisation in a day case procedure. Access is gained through a small skin incision and once placed inside the disc, a small pair of forceps is used to physically remove disc nucleus (just as surgeons do through an open approach), then a semi-steerable RF catheter is used to further ablate the nucleus and reduce the possibility of late relapse, finally the same catheter is used with a different setting to heat seal and denervate the posterior annulus. The procedure can be controlled and viewed endoscopically.
This is suitable for larger, contained slipped discs (ie not protruding through a fully torn annulus), including those causing sciatica, discogenic back pain and related syndromes.
Annular Heating Denervation or Pulse RF
There are a range of other techniques based on the idea of heat-denervaton of the back of the disc annulus where most of the damage occurs. As with Rf denervation of the facet joint, heating between 45° and 80°disrupts small nerve fibres but does not burn or char tissue and so targeted heating in this range can be used to selectively denervate (remove the nerves) and so desensitize the treated tissue. Also, heating the protein of the annulus may also seal fissures (reducing the effects of internal pressure) and allow contraction and so reduce the volume of the disc (reducing the effects of pressure on nerves and other structures behind).
The original technique of this kind is called IDET (Smith and Nephew) a simpler alternative is called DISKIT (Neurotherm) which I tend to use and there is an equivalent called Biacuplasty(Bayliss Medical). My colleague, Dr Ron Cooper in Coleraine, NI uses DISKIT successfully, my own experience is limited but positive and the the technique is technically straightforward, less expensive in equipment and suitable for discs which are not bulging or severely damaged.
Pulsed Radiofrequncy in Disc Pain
This is a simple technique where an electrode is passed into the disc nucleus and pulsed Rf energy is passed into the disc using specifically developed protocols shared with me by Dr Olav Rohoff. Dr Rohoff’s published experience suggest this is successful in about 55-60% and can be a durable treatment lasting up to 2 years and I would agree with this. IN practice success rates at this level feel a bit “hit and miss” but since Pulse Rf is entirely non destructive and no tissue is removed, it can be a useful if there is no better option. Where cobaltion percutaneous decompression is not available to a patient, I try to assist by undertaking a pulse RF of the disc at the time of discography or at other times as indicated.
An alternative to using heat energy to denervatre the annulus is to use pulsed radiofrequency energy (Pulse RF) in the same way (DISKIT, Neurotherm). This seems to produce the same results but is less painful post procedure (note most PRF techniques have 3 phases of recovery – better, worse, better over a few weeks – no one is sure why). Since PRF modifies but does not destroy or damage tissue in any way, it is an attractive treatment for patients whose discs are not significanlty damaged and may even appear normal on an MRI scan (I recently treated a young lady dancer in this way for example).