Recommendations for research
The guideline committee has made the following recommendations for research. The committee's full set of research recommendations is detailed in the full guideline.
What is the clinical and cost effectiveness of benzodiazepines for the acute management of low back pain?
Guidelines from many countries have said that muscle relaxants should be considered for short-term use in people with low back pain when the paraspinal muscles are in spasm. The evidence for this mainly comes from studies on medications that are not licensed for this use in the UK. The 2009 NICE guideline on low back pain recommends to consider prescribing diazepam as a muscle relaxant in this situation, but the evidence base to support this particular medicine is extremely small. Benzodiazepines are not without risk of harm, even for short-term use. Because of this, there is a need to find out if diazepam is clinically and cost effective in the management of acute low back pain.
What is the clinical and cost effectiveness of codeine with and without paracetamol for the acute management of low back pain?
Codeine, often together with paracetamol, is commonly prescribed in primary care to people presenting with acute low back pain. This often happens with people who cannot tolerate non-steroidal anti-inflammatory drugs (NSAIDs) or when a person has contraindications to these medications. Although there is evidence that opioids are not effective in chronic low back pain, there are relatively few studies that look at their use for acute low back pain (a problem commonly seen in primary care). Also, it is not known if using paracetamol and codeine together has a synergistic effect in the treatment of back pain.
What is the clinical and cost effectiveness of radiofrequency denervation for chronic low back pain in the long term?
Radiofrequency denervation is a minimally invasive and percutaneous procedure performed under local anaesthesia or light intravenous sedation. Radiofrequency energy is delivered along an insulated needle in contact with the target nerves. This focused electrical energy heats and denatures the nerve. This may allow axons to regenerate with time, requiring the repetition of the radiofrequency procedure.
The length of pain relief after radiofrequency denervation is uncertain. Data from randomised controlled trials suggest relief is at least 6–12 months but no study has reported longer-term outcomes. Pain relief for more than 2 years would not be an unreasonable clinical expectation. The economic model presented in this guideline suggested that radiofrequency denervation is likely to be cost effective if pain relief is above 16 months.
If radiofrequency denervation is repeated, we do not know whether the outcomes and duration of these outcomes are similar to the initial treatment. If repeated radiofrequency denervation is to be offered, we need to be more certain that this intervention is both effective and cost effective.
What is the clinical and cost effectiveness of image-guided compared with non-image-guided epidural injections for people with acute sciatica?
Epidural injection of treatments, including corticosteroids, is commonly offered to people with sciatica. Epidural injection might improve symptoms, reduce disability and speed up return to normal activities. Several different procedures have been developed for epidural delivery of corticosteroids. Some practitioners inject through the caudal opening to the spinal canal in the sacrum (caudal epidural), but others inject through the foraminal space at the presumed level of nerve root irritation (transforaminal epidural).
Some people believe transforaminal epidurals might be most effective because they deliver corticosteroids directly to the region where the nerve root might be compromised. But because transforaminal epidural injection needs imaging, usually within a specialist setting, this potentially limits treatment access and increases costs. Caudal epidural injection can be done without imaging, or with ultrasound guidance in a non-specialist setting. But it has been argued the treatment might not reach the affected nerve root, meaning this method might not be as effective as transforaminal injection.
Evidence that one method is clearly better than the other is currently lacking. Use of the 2 methods varies between healthcare providers, and people whose sciatica does not respond to caudal corticosteroid injection might go on to have image-guided epidural injection. This means people with sciatica might currently experience unnecessary symptoms at unnecessary cost to the NHS than they would if the most clinically and cost-effective way of delivering epidural corticosteroid injections was always used.
Should people with low back pain be offered spinal fusion as a surgical option?
An increasing number of procedures have been proposed for surgically managing low back pain. One of these procedures is surgical fixation with internal metalwork applied from the back, front, side, or any combination of the 3 routes. The cost of these operations has risen, and now that minimally invasive approaches are used, more of these operations are done with uncertain benefit.
As well as the cost, surgery can lead to complications – some studies report around a 20% complication rate in the short to medium term. There have been several studies (both randomised and cohort) looking at the clinical effectiveness of spinal fusion versus usual care, no surgery, different surgeries, and other treatments. Overall, the studies do not show a clear advantage of fusion but do show some modest benefit for some elements of pain, function and quality of life. The studies also show healthcare use was lower. It is not known what treatments should be tried before surgery is considered. The evidence from the studies was weak because of low numbers of patients, large crossover and in-case selection bias. This means there is a need for a large, multicentre randomised trial with sufficient power to answer these important questions.