There are many different ways to report on the findings of a clinical study: this one intrigued me because it looks at who does well after radiofrequency and injection treatments for low back pain.
In a post hoc study of 161 people receiving these treatments for back pain and sciatica, subsequently treated in an open prospective follow-up period, those with positive psychosocial features did well, while those who were psychologically ‘more vulnerable’ did not do as well.
The study is interesting for a couple of reasons – it was part of a double-blind study of radiofrequency neurotomy (RNF), in which patients received sham RF lesioning (no current was applied to the nerve, although anaesthetic was still provided). The major finding of this study was that ‘the vast majority of patients failed to respond according to the primary combined outcome measure, comprising VAS, physical activity scores, and analgesics scores.’ The authors found, however, that ‘in each trial, a comparable statistically significant VAS reduction was found in both RF and control lesion groups. It was concluded that in these selected groups of patients, both RF and sham (local anesthetic injection) treatment should be regarded as about equally effective.’
For the 9 months following this first treatment, these patients were provided with follow-up – and ‘treated as found necessary on clinical grounds in an open prospective followup period of 9 months. Additional treatment consisted of a variable combination of RF and/or steroid injection treatments.’ During this time, however, these patients didn’t receive any other treatment, whether surgical or cognitive behavioural.
A comprehensive battery of questionnaires were completed by the participants, and the researchers used the responses to identify five separate groups of patients: “psychologically negative”, or people who didn’t do well and experienced high interference, reduced control, low mood, high anxiety and so on; “adaptive manager”, or people who coped pretty well and regained or remained active; “inflexible qualities”; presenting as resigned, rigid, and feeling wronged; “supporting partner”, those with a rewarding, supportive and helpful partner; and “strong ego”, or those with high self-esteem, dominance, and high social adequacy.
The findings? Well, those in the ‘adaptive manager’ group did well at three months, reporting a 50% reduction in pain – and a similar finding at the long-term followup point also.
Those who were ‘psychologically negative’ didn’t do as well, especially at the long term followup.
The authors summarise by saying ‘patients characterized by reduced pain and interference levels, reasonable physical activities levels, positive expectations, and reasonable physical and social functioning, perform more favorably on these interventions.’
Although they don’t suggest that people who lack these resilient characteristics shouldn’t get RF and injection treatments, I’d suggest that these people will also need a cognitive behavioural approach to effectively manage the psychosocial components of their disability.
The real question is: do clinicians who treat patients with these interventions routinely assess the psychosocial profiles of their patients? Or do they simply follow the biomedical model and manage them accordingly?
van Wijk, R., Geurts, J., Lousberg, R., Wynne, H., Hammink, E., Knape, J., & Groen, G. (2008). Psychological Predictors of Substantial Pain Reduction after Minimally Invasive Radiofrequency and Injection Treatments for Chronic Low Back Pain Pain Medicine, 9 (2), 212-221 DOI: 10.1111/j.1526-4637.2007.00367.x