Nyheder

Total Disc Replacement for Chronic Discogenic Low-Back Pain

A Cochrane Review.

• ABSTRACT: Study Design. Systematic literature review.
• Objective. To assess the effect of total disc replacement for chronic low back pain due to lumbar degenerative disc disease compared to fusion or other treatment options.Summary of Background Data. There is an increasing use in disc replacement devices for degenerative disc disease, but their effectiveness compared to other interventions such as fusion of the motion segment or conservative treatment remains unclear.Methods. A comprehensive search in CENTRAL, MEDLINE, EMBASE, BIOSIS ClinicalTrials.gov, and FDA trials register was conducted. Randomized controlled trials (RCT) comparing total disc replacement with any other intervention for degenerative disc disease were included. Risk of Bias was assessed using the criteria of the Cochrane Back Review Group. Quality of evidence was graded according to the GRADE approach. Two review authors independently selected studies, assessed risk of bias and extracted data. Results and upper bounds of confidence intervals were compared against predefined clinically relevant differences.Results. We included seven RCT's with a follow-up of 24 months. There is risk of bias in the included studies due to sponsoring and absence of any kind of blinding. One study compared disc replacement against rehabilitation and found a significant advantage in favor of surgery, which, however, did not reach the predefined threshold. Six studies compared disc replacement against fusion and found that the mean Improvement in VAS back pain was 5.2 mm higher (2 studies, 95% CI 0.2 to 10.3) with a low quality of evidence. The improvement of Oswestry score at 24 months in the disc replacement group was 4.3 points more than in the fusion group (5 studies; 95% CI 1.85 to 6.68) with a low quality of evidence. Both upper bounds of the confidence intervals were below the predefined clinically relevant difference.
• Conclusions. Although statistically significant, the differences in clinical improvement were not beyond generally accepted boundaries for clinical relevance. Prevention of adjacent level disease and/or facet joint degeneration was not properly assessed. Therefore, because we believe that harm and complications may occur after years, we believe that the spine surgery community should be prudent about adopting this technology on a large scale, despite the fact that total disc replacement seems to be effective in treating low back pain in selected patients, and in the short term is at least equivalent to fusion surgery. Jacobs WC et al. Spine (Phila Pa 1976). 2012 Sep 19.

Epidural steroids, etanercept, or saline in subacute sciatica

A multicenter, randomized trial. Epidural steroid injections may provide modest short-term pain relief for some adults with lumbosacral radiculopathy, but larger studies with longer follow-up are needed to confirm their benefits. Cohen SP et al. Ann Intern Med. 2012 Apr 17;156(8):551-9.

Puncture of a disc and application of nucleus pulposus induces disc herniation-like changes and osteophytes

An experimental study in rats. It has been observed that puncture of a lumbar disc may induce formation of a nodule on the surface of the disc and osteophytes. It is not known if this is based on the presence of a foreign tissue or specifically by the presence of nucleus pulposus or on the disc injury. In this study these mechanisms were separated by comparing disc puncture with application of nucleus pulposus without disc injury, with superficial disc injury without nucleus pulposus and with application of fat. Fifty rats underwent facetectomy of the left L4-5 facet. Ten additional rats were used as donor rats. The rats were exposed to disc puncture (n=10), application of homologous nucleus pulposus (n=10), application of homologous fat tissue (n=10), superficial disc injury (n=10) and ten rats served as control. After 3 weeks the rats were examined macroscopically regarding presence of disc nodules and osteophytes. A limited histological analysis was performed to obtain a microscopic overview of any observed changes. In rats with application of fat, superficial disc injury and in sham controls there were almost no changes observed. However, in rats with disc puncture and applied nucleus pulposus there were clear disc nodules and osteophytes noted. Microscopically the nodules comprised granulation tissue and the osteophytes cortical bone. In conclusion, the data indicate that the presence of nucleus pulposus is more likely to be responsible for the formation of disc nodules and osteophytes than disc injury or the presence of a foreign tissue. This may provide new insights in the mechanisms regarding the formation of disc herniations and osteophytes. Olmarker K. Open Orthop J. 2011 Apr 28;5:154-9.

A consensus approach toward the standardization of back pain definitions for use in prevalence studies

These definitions provide standards that may improve future comparisons of low back pain prevalence figures by person, place and time characteristics, and offer opportunities for statistical summaries. Dionne CE et al. Spine (Phila Pa 1976). 2008 Jan 1;33(1):95-103.

Efficacy of tumor necrosis factor-alpha blockade for severe sciatica?

The domain of sciatica is at the edge of a mini revolution. For ten years evidence have been accumulating in favour of a local inflammation rather than a pathology resulling only from a nerve compression. This hypothesis has first been strengthened by the discovery of inflammatory mediators in human herniated discs and then by animal models. These models have demonstrated the impossibility for nerve root compression to produce sciatica in the absence of inflammation and the importance of proinflammatory cytokines in this pathology. TNF-alpha have been proved to be the most important inflammatory cytokine and TNF-alpha modulators has been most effective in the treatment of these models. Two pilot studies realized on humans seem to confirm these experimental data. A multicenter randomised, double-blind, placebo controlled study is being planed in Switzerland. Genevay S, Guerne PA, Gabay C. Rev Med Suisse Romande. 2004 Sep;124(9):543-5. Review. French.

MR imaging and CT in osteoarthritis of the lumbar facet joints

With regard to osteoarthritis of the lumbar facet joints there is moderate to good agreement between MR imaging and CT. When differences of one grade are disregarded agreement is even excellent. Therefore, in the presence of an MR examination CT is not required for the assessment of facet joint degeneration. Weishaupt D, Zanetti M, Boos N, Hodler J. Skeletal Radiol. 1999 Apr;28(4):215-9.

The tissue origin of low back pain and sciatica

A report of pain response to tissue stimulation during operations on the lumbar spine using local anesthesia. In an effort to define the origin of low back pain and sciatica, 193 patients were carefully studied using progressive local anesthesia. These patients had surgery for herniated discs, spinal stenoses, or both. Various tissues were stimulated during the performance of these lumbar spinal operations. This article discusses our observations and the results of that study. Kuslich SD, Ulstrom CL, Michael CJ. Orthop Clin North Am. 1991 Apr;22(2):181-79.