Predictive value of MRI in decision making for disc surgery in sciatica.
Decisions on imaging for spinal pain can be difficult. Most guidelines recommend delaying imaging for back pain in the absence of strongly suspected serious pathology. For patients with signs of radiculopathy, it is still recommended that imaging be delayed. A new study on the predictive value of MRI supports the suggested delay in imaging patients with sciatica [1]. Researchers used imaging data from 142 patients with sciatica, 55 of which received surgery after a period of conservative care, to identify predictors of surgical management. MRI was unable to distinguish features (e.g. size or location of disc herniation) of patients who had delayed surgery and those who did not. In other words, structural findings on MRI bear no consistent relationship to whether or not a person receives surgery for sciatica. These findings provide evidence that early MRI imaging in patients with sciatica is not useful for clinical decision making.
Validity and reliability of the French version of the STarT Back Screening Tool for patients with low back pain.
The STarT Back Tool has been gaining traction since successfully used in a model of stratified treatment for low back pain. This trial, published in the Lancet [2], demonstrated that screening and treating patients according to their risk factors for chronicity was superior to usual care. However, screening tools such as STarT Back can perform poorly when used outside the sample where they were developed [3]. For these tools to be generalisable in primary care they need to be validated. STarT Back has been validated 3 countries and is undergoing validation in another 10 countries. The latest to be published is the French version [4]. When the tool was tested in a French LBP sample, it demonstrated high reliability and moderate to high internal validity. Internal validity refers to how well scores on the STarT Back tool correlate with other instruments that measure the same construct e.g. disability. It should be noted that this French study did not evaluate the predictive validity of the tool. However, the developers would argue that prediction is not the STarT Backs primary purpose. The idea behind the tool is to stratify patients and match appropriate treatments. As far as Australian primary care goes, STarT can be useful to inform decisions about referral. For example, patients identified as medium and high risk may benefit more from referral to a physiotherapist, than someone identified as low risk.
Back complaints in older adults: the prevalence of neuropathic pain.
Neuropathic pain is a term used to describe pain related to disorder in the somatosensory system. This disorder can involves peripheral mechanisms e.g. peripheral nerve lesions (peripheral sensitisation), and central mechanisms e.g. dorsal horn overactivity (central sensitisation). Neuropathic pain can manifest as burning, electric shocks, itching and numbness. Recently researchers have been interested in the prevalence of neuropathic pain in LBP. Studies have reported that the prevalence of neuropathic pain in low back pain is between 15 - 50%. A study just published on older adults found that on 5% of older adults with LBP (>55yr) could be classified as having neuropathic pain using a validated screening tool [5]. This slightly unexpected result needs to be replicated in future studies. The presence of neuropathic pain is likely to influence a number of decisions in clinical practice including education, medication and exercise prescription.
Evidence for surgery in degenerative lumbar spine disorders.
More research has emerged on the efficacy of spinal surgery for degenerative lumbar spine disorders. The latest review of systematic reviews published in Best Practice & Research concluded that surgery is only indicated for relief of leg pain where there is clear indication of disc herniation, spondylolisthesis or spinal stenosis [6]. Out of 20 systematic reviews, there were no significant effects of surgery when compared to conservative management in the short or long term. This review adds further evidence to the debate on surgical management of LBP. Considering the complexity of LBP, it is unsurprising that simply treating structural factors is ineffective. To date no treatment had been consistently shown to be superior to good education and a well-designed rehabilitation program for patients with LBP.