12.3.1.1IDET

One systematic review (Freeman-Brian, J. C., 2006) reviewed the evidence of clinical efficacy for IDET (intra-discal electrothermal therapy). The PubMed, Medline and the Cochrane Library databases were searched for RCTs and cohorts published up to January 2006. They specified in the inclusion criteria they were looking for at least one of the four following primary outcomes: pain intensity (VAS), back functional status (Oswestry Disability Index), global measurement of overall improvement, return to work.

Three randomized controlled trials were identified (in addition to cohort studies), two of them being on the effectiveness of IDET (the third one was on a slightly different intervention, namely percutaneous intradiscal radio-frequency thermo-coagulation (PIRFT)). The randomized controlled trials compared IDET to sham and primary outcomes were pain (VAS), the Oswestry Disability Index (ODI), SF-36 General Health Questionnaire, Zung Depression Index.

The study on PIRFT showed no statistically significant differences in outcomes between the two groups. The RCT on IDET, where 64 patients were randomized showed significantly better improvements in VAS in the treatment group than in the sham group (P =0.045). However, only 50% of patients randomized to the intervention group benefited appreciably from IDET. The other RCT on IDET failed to show any statistically significant or clinical important differences in the outcomes between groups.

The authors concluded that the 2 RCTs addressing the effectiveness of IDET provide inconsistent evidence, and that the current published evidence does not provide clear evidence of benefit. The overall conclusion was that the evidence for efficacy of IDET remains weak and has not passed the standard of scientific proof. Since this systematic review was published, Freeman published a more recent one (Freeman, Brian. J. C. and Mehdian, Roshana., 2008), however, the same studies were included and no new relevant studies were identified.

This was a well conducted systematic review with a low risk of bias

12.3.1.2Spinal Fusion

A meta-analysis of RCTs was conducted to compare surgical to non-surgical treatment of chronic low back pain (Ibrahim, T., Tleyjeh, I. M., and Gabbar, O., 2008a). The results in a published erratum were used to inform this guideline (Ibrahim, T., Tleyjeh, I. M., and Gabbar, O., 2008b). A search of 4 bibliographic databases (Medline, Embase, Cinahl, Science Citation index) was conducted to identify RCTs published between the dates 1966–2005. Trials must have reported an Oswestry disability Index (ODI) as an outcome measure to be included and the comparators were physical therapy and cognitive therapy. Four relevant papers (Brox, I. J., Sorensen, R., Friis, A. et al, 2003; Ekman, P., Möller, H., and Hedlund, R., 2005; Fairbank, J., Frost, H., Wilson, MacDonald J. et al, 2005; Fritzell, P., Hägg, O., Wessberg, P. et al, 2001) were found that met the inclusion criteria and a meta-analysis was carried out. Ekman et al (2005) was not included in the meta-analysis as it was regarding isthmic spondylolisthesis. The three studies included in the meta-analysis are also included in the Mirza (2007) systematic review. The interventions were all a type of lumbar fusion surgery (see Mirza, 2007 for more details.)

The meta-analysis, in a published erratum that changes conclusion of the original paper, showed a benefit from surgery of 4.87 (95%CI 1.62 to 8.12 P =0.003) as measured on the ODI.

This was a well conducted meta-analysis with a low risk of bias.

One systematic review reviewed the efficacy of lumbar fusion surgery for chronic back pain treatment (Mirza, S. K. and Deyo, R. A., 2007). The MEDLINE database was searched as well as references from a Cochrane Review update for RCTs published to May 2006. The inclusion criteria specified RCTs comparing surgical to nonsurgical treatment for discogenic back pain.

Four randomized controlled trials were found, all of which used lumbar fusion surgery of some type. One study (Fritzell, P., Hägg, O., Wessberg, P. et al, 2001) used one of three techniques: 1) Posterolateral fusion (PLF) using iliac crest autograft without fixation 2) Posterolateral fusion using pedicle screws and iliac crest autography, 3) Anterior Lumbar interbody Fusion (ALIF) or Posterior Lumbar Interbody Fusion (PLIF) using bone blocks cut from the iliac crest. Two studies (Brox, I. J., Sorensen, R., Friis, A. et al, 2003; Brox, Jens, I, Reikerås, Olav, Nygaard, Øystein et al, 2006) used posterolateral fusion using pedical screws and iliac crest autograft. One study (Fairbank, J., Frost, H., Wilson, MacDonald J. et al, 2005) used spinal stabilisation using any technique, devices and graft material chosen by the surgeon. The comparators were non-surgical treatment, such as physical therapies, cognitive interventions and intensive rehabilitation. Outcome measures included: VAS, ODI, Million score and General Function Score, Zung Depression Scale.

Results from one study (Fritzell, P., Hägg, O., Wessberg, P. et al, 2001) found that at 2 years there was a reduction in pain for the surgical group by 33% (64 to 43), compared with 7% (63 to 58) in the nonsurgical group (P =0.0002). Disability and back related issues were also reduced significantly. More people in the surgical group felt better and were able to go back to work. In the other three studies there was no significant difference between groups. Fairbanks et al did have significant results for ODI at 2 years but this was found non-significant when missing data were imputed (Fairbank, J., Frost, H., Wilson, MacDonald J. et al, 2005).

The authors concluded surgical procedures may be more efficacious when compared to unstructured nonsurgical care but this is not so when compared to structured cognitive behaviour therapy. However, it cannot be firmly concluded as there were methodological problems with the RCTs which were included.

This was a well conducted systematic review with a low risk of bias

12.3.1.3Radiofrequency Facet Joint Denervation

One randomized controlled trial assessed the efficacy of percutaneous radiofrequency articular facet denervation for low back pain (Leclaire, R., Fortin, L., Lambert, R. et al, 2001). Seventy participants were included in the RCT, other inclusion criteria were: aged from 18 to 65 years, with lower back pain for more than 3 months duration with previous significant relief for at least 24 hours during the week after facet joint injection. Participants were excluded if they had sciatic pain with neurologic deficit, lower back pain not relating to a mechanical disorder, had undergone low back surgery. A total of 36 patients were randomised to percutaneous radiofrequency articular facet denervation, and 34 were randomised to the same procedure without the denervation. Outcome measures taken at 4 and 12 weeks included the Roland Morris score (RMDQ), Oswestry and VAS.

Treatment effect results at four weeks were 6.2 (− 1.3 to 13.8, P =0.05), 0.6 (− 4.5 to 5.7) and 4.2 (− 6.9 to 15.4) for the RMDQ, ODI and pain scores respectively. At twelve weeks the treatment effect results were 2.6 (− 6.2 to 11.4), (− 3.2 to 7) and − 7.6 (− 20.3 to 5.1) for the RMDQ, ODI and pain scores respectively.

The authors concluded that radiofrequency facet joint denervation is not shown to be of benefit as determined by functional disability at 12 weeks and no effect on pain at 4 or 12 weeks.

This was a well conducted RCT with a low risk of bias

One RCT evaluated the effect of percutaneous radiofrequency zygapophysial joint neurotomy in reducing pain and physical impairment in patients with pain from lumbar zygapophysial joints (Nath, Sherdil, Nath, Christine Ann, and Pettersson, Kurt, 2008). 40 patients were included, n=20 in the active treatment (intervention group) and n=20 in the placebo (control group) and followed up at 6 months. Adult patients were included if they had continuous low back pain for at least 2 years, had not responded to previous treatment and were able to identify at least one component of their pain which could be attributed to one or more lumbar Zygoapophyseal joints, had paravertebral tenderness and obtained at least 80% relief of pain following controlled, medial branch blocks. Both groups received the same procedure except that the placebo group received no current from electrodes and the tip stayed at room temperature. Lidocaine 1% and bupivacaine 2ml was given to anaesthetise the nerves and denervation was achieved by multiple lesions.

Patients’ global assessment of pain showed a significant reduction in pain for the intervention group. VAS generalized pain reduction, back pain reduction and referred leg pain reduction were significantly reduced in the intervention group compared to the control group (P =0.004). Thus the author concluded that RF neurotomy can be used successfully as a complement to other interventions to reduce pain in carefully selected patients. It should be noted that the groups were significantly different (intervention group had higher pain) at the start of the trial which could have confounded results. The sample size was also very small.

This was an RCT with a high risk of bias

One RCT assessed the efficacy of radiofrequency facet joint denervation (RF) compared to sham procedure for treatment of chronic low back pain (van Wijk, Roelof. M. A. W., Geurts, Jos. W. M., Wynne, Herman. J. et al, 2005). Eighty one participants were included in the RCT. The inclusion criteria was aged over 17 years, lower back pain with or without radiating pain into the upper leg for more than 6 months with focal tenderness over facet joints, no radicular symptoms, at least 50% pain relief on a VAS 30 minutes after a diagnostic block. Forty patients were randomised to the RF group and forty one to the sham procedure. Outcome measures taken at 3 months included VAS, physical activities scale, use of analgesics scale, global perceived effect (back pain), SF-36, Zung.

Success in the combined outcome measure showed no significant differences between the groups 27.5% in intervention and 29.3% in control (P =0.86). No differences in VAS back or leg or medication use between two groups. More people in the intervention group reported greater than 50% reduction in pain at 3 months 61.5% vs 39% P = 0.044.

The authors concluded that there were no differences between the two procedures except a significant improvement in VAS scores. The global perceived effect was in favour of radiofrequency.

This was a well conducted RCT with a low risk of bias

12.3.1.4Radiofrequency Denervation of the Ramus communicans nerve

One randomized controlled trial assessed the efficacy of percutaneous radiofrequency thermocoagulation of the ramus communicans nerve (Oh, Wan. Soo. Shim Jae. Chol., 2004). Forty-nine patients who suffered chronic discogenic low back pain at only 1 painful vertebral level, and whose pain continued after undergoing IDET were randomly assigned to 1 of 2 treatment groups. The lesion group (n=26) received RF thermocoagulation of the ramus communicans nerve, while patients in the control group (n=23) received an injection of lidocaine without radiofrequency. To be included in the study patients had to have been suffering from discogenic low back pain for over 1 year, a history of failed conservative treatment of several months duration, and have failed to notice significant improvement in pain 9 months after undergoing IDET (discogenic pain being confirmed prior to IDET by means of provocative discography at low pressurization). Exclusion criteria were radiculopathies and other neurologic abnormalities, combined facet joint or myofascial pain; facet-joint induced pain (assessed with diagnostic block); Myofascial pain, paraspinalis muscle spasm induced pain with a positive response to trigger point injection and physiotherapy was also excluded; verbal decline; failure to provide written informed consent; spinal stenosis; spinal instability; multilevel disc lesion; previous spinal surgery; history of excessive bleeding or coagulopathy; obvious psychological problems.

Patients in the lesion group (n=26) received electrostimulation at 50Hz, 0.8–1.0 volt. The location that provoked a deep aching pain identical to the usual pain of the patient was confirmed. 1% lidocaine was then injected and followed by RF thermocoagulation at 65degrees C for 60 seconds. Contrast medium was injected to confirm lack of spinal nerve root. After RF thermocoagulation, 2mL of preservative-free 1% lidocaine was injected along with 40mg of sterile triamcinolone acetonide for the purpose of preventing postoperative neuritis. The control group (sham group) (n=23) received an injection of 2mL of preservative-free 1% lidocaine instead of RF thermocoagulation.

Outcome measures taken at 4 months were the VAS and SF-36 bodily pain and physical functioning. The patient-reported VAS pain scores were significantly lower (P <0.05) in the lesion group, and the scores on the SF-36 bodily pain and physical function subscales were significantly in favour of the RF lesion group (P <0.05 for both).

The authors concluded that in patients with chronic discogenic low back pain, percutaneous RF denervation of the ramus communicans nerve should be considered as a treatment option.

This was a well conducted RCT with a low risk of bias

Results (base case)

The mean cost (Standard Deviation) for patients in the surgery arm was £7830 (SD=£5202) and for patients in the IRP it was £4526 (SD=£4155).

The difference of £3304 (£2317 to £4291, P <0.001) was in favour of the IRP group. At 24 months mean QALYs for the surgery arm was 1.004 (SD=0.405) and for IRP it was 0.936(SD=0.431). The difference was 0.068 (− 0.02 to 0.156). Therefore the incremental cost per QALY of using a policy of immediate surgery was £48,588 (− £279,883 to £372,406). Probablistic sensitivity analysis shows that if decision makers are willing to pay £30,000 for a QALY, at two years, the chance that surgery will be cost effective is less than 20%.

Sensitivity analysis

Five scenarios were chosen for sensitivity analysis.

1. If patients who had surgery had the least expensive technique the cost difference between the two groups would fall to £2403 which would result in a lower incremental cost per QALY of £35,338(− £188,876 to £410,404)

2. If patients who had surgery had the most expensive technique the cost difference would rise and the resulting incremental cost per QALY would rise to £60,765 (− £420,210 to £617,081)

3. If QALY differences between the two groups was maintained for a further two years then the incremental cost per QALY would fall to £25,398 (£13,121 to £75,916).

4. If patients in the study continued to receive both treatments in years three, four and five at the rates observed in years one and two, the incremental cost per QALY would fall to £16,824 (− £156,358 to £138,911)

5. If patients in the study continued to receive both treatments in years three, four and five at half the rates observed in years one and two, the incremental cost per QALY would fall to £31,838 (− £407,056 to £283,783)

This study shows that in the base case analysis the incremental cost per QALY of having a policy of immediate surgery for chronic low back pain is £48,588. And if decision makers are willing to pay £30,000 for a QALY, at two years, the chance that surgery will be cost effective is less than 20%. Cost per QALY would be less than £30,000 if either QALY differences between the two groups was maintained for a further two years, or if patients in the study continued to receive both treatments in years 3, 4 and 5 at the rates observed in years one and two.

It should be noted that the inclusion criteria specified that patients who were candidates for surgical stabilisation of the spine were eligible only if the clinician and patient were uncertain which of the study treatment strategies was best.