Surgery for Sciatica - Informed Patient Decision Making is the Key
I would like to congratulate Wilco Peul and his colleagues on their attempt to provide good quality evidence which can be used to help advise patients when discussing the management of their sciatica.1 This is a common problem and it is clearly important that we have an understanding of the risks, benefits and costs of surgery.
However, I am concerned that this article may lead to some patients being denied the opportunity discuss surgery when it may be of benefit to them.
For those involved in spinal surgery it is a day to day observation that if a compressed nerve root is causing pain then decompressing the nerve root provides a very good chance of alleviating the pain. This observation is supported by the author’s results and endorsed by the 44% of patients in the conservative treatment arm who eventually underwent surgery. Results which are similar to those of the SPORT trial.2
Accepting that nerve root decompression is effective in relieving pain but that the condition of disc prolapse often resolves spontaneously, the long standing debate has been over the timing of surgery and the long term outcome.
What this paper adds is confirmation that surgery provides a good chance of rapid relief from pain and that the complication rate is low. It cannot be used to conclude that after 12 months whether you have surgery or not the outcome is likely to be the same. This is because of the very high failure rate of conservative management. Had 44% of patients not converted to surgery one has to presume that dissatisfaction with the conservative arm would have been greater.
One of the authors’ conclusions is that,” well-informed patients, rather than physicians, should decide whether and when to have surgery”. Although I am not sure what this paper provides to support the claim that it is ,”What this study adds”, I very much agree with this sentiment and would have thought it prerequisite for any surgical intervention. However, application of this principle creates an apparent contradiction with the European guidelines referred to by Mr Fairbank in his editorial.3 He reports that, “Surgery should be performed before eight weeks only in patients with progressive neurological deficit, which can be detected by magnetic resonance imaging”(sic).
Given that we have an effective treatment for radicular pain it would appear inhumane to deny a patient surgery (or the opportunity to discuss surgery or other interventions e.g. dorsal root ganglion block) should they be in significant pain. They should be the ones who decide whether the pain is of such intensity and has lastest long enough that the potential benefits of surgery outweigh the risks. This assumes that the decision is made having had a full and frank discussion of the potential risks and benefits. To this end it is imporatant limitations of published data are understood.
To have 20% of patients dissatisfied at 2 years is very disappointing. It would be interesting to know more about this group of patients. Were the reasons for dissatisfaction similar in the two groups? How many of the conservatively managed patients who were dissatisfied complained of persisting symptoms for which they had originally consulted their GP? Of those in the surgical group, how much of their dissatisfaction could be potentially attributed to recurrent or a residual nerve root compression?
I note the average length of hospital stay was 3.7 days. Since microdiscectomy is regularly performed as a day case it is difficult to understand why the length of stay was so long. It is also hard to believe that this would not have an impact on the economic considerations.
The inclusion criteria required that a patient not only describe a dermatomal pattern of pain but also demonstrated, concomitant neurological disturbances which correlated with the affected nerve root. Since the patient's primary complaint was of pain and that the surgical treatment is effective for the symptom of pain it is difficult to understand why the presence of additional neurological disturbance was required.
Although the authors report that there was no significant difference in back pain suffered by the surgical group compared with the conservatively managed group the illustrations clearly demonstrate a significant difference at the 8 and 12 week assessments. The significance of this difference may have been greater had the pain score for back pain been higher. Since some authorities will only consider operating for sciatica if the leg pain is greater than the back pain it would be interesting to know whether this criteria was employed by the authors? If this were the case, it may explain the discrepancy between their study and that recently reported by the SPORT trial.2 This reports a greater improvement in back pain following discectomy than with non-operative treatment and that this difference was maintained at two years.
It is also important to point out to the wider readership of your journal that the authors have selected to examine patients with nerve root compression secondary to an intervertebral disc prolapse. It is well known that symptoms caused by a disc prolapse are likely to improve with time. However, more patients probably suffer from nerve root compression as a result of other degenerative change in their spine such as facet hypertrophy and disc bulge. The natural history of this condition is likely to be different from that of disc prolapse. Thus, it is important that a distinction is made between the treatment of sciatica due to disc prolapse and sciatica due to other causes of nerve root compression.
1. Fairbank, J. Prolapsed intervertebral disc. BMJ, Jun 2008;336:1317 – 1318
2. Peul WC et al. Prolonged conservative care versus early surgery in patients with sciatica caused by lumbar disc herniation: two year results of a randomised controlled trial. BMJ Jun 2008;336:1355 – 1358.
3. Pearson AM et al. SPORT lumbar intervertebral disk herniation and back pain does treatment, location or morphology matter? Spine, Feb 2008;33(4):428-435.
Competing interests: None declared
Competing interests: No competing interests