Chiropractors are notorious for their overuse and misuse of x-rays for non-specific back and neck pain as well as other conditions. A recent study from the US has shown that the rate of spine radiographs within 5 days of an initial patient visit to a chiropractor is 204 per 1000 new patient examinations. Considering that X-rays are not usually necessary for patients with non-specific back pain, such rates are far too high. Therefore, a team of US/Canadian researchers conducted a study to evaluate the impact of web-based dissemination of a diagnostic imaging guideline discouraging the use of spine x-rays among chiropractors.
They disseminated an imaging guideline online in April 2008. Administrative claims data were extracted between January 2006 and December 2010. Segmented regression analysis with autoregressive error was used to estimate the impact of guideline recommendations on the rate of spine x-rays. Sensitivity analysis considered the effect of two additional quality improvement strategies, a policy change and an education intervention.
The results show a significant change in the level of spine x-ray ordering weeks after introduction of the guidelines (-0.01; 95% confidence interval=-0.01, -0.002; p=.01), but no change in trend of the regression lines. The monthly mean rate of spine x-rays within 5 days of initial visit per new patient exams decreased by 10 per 1000, a 5.26% relative decrease after guideline dissemination.
The authors concluded that Web-based guideline dissemination was associated with an immediate reduction in spine x-ray claims. Sensitivity analysis suggests our results are robust. This passive strategy is likely cost-effective in a chiropractic network setting.
These findings are encouraging because they suggest that at least some chiropractors are capable of learning, even if this means altering their practice against their financial interests – after all, there is money to be earned with x-ray investigations! At the same time, the results indicate that, despite sound evidence, chiropractors still order far too many x-rays for non-specific back pain. I am not aware of any recent UK data on chiropractic x-ray usage, but judging from old evidence, it might be very high.
It would be interesting to know why chiropractors order spinal x-rays for patients with non-specific back pain or other conditions. A likely answer is that they need them for the diagnosis of spinal ‘subluxations’. To cite just one of thousands of chiropractors with the same opinion: spinography is a necessary part of the chiropractic examination. Detailed analysis of spinographic film and motion x-ray studies helps facilitate a specific and timely correction of vertebral subluxation by the Doctor of Chiropractic. The correction of a vertebral subluxation is called: Adjustment.
This, of course, merely highlights the futility of this practice: despite the fact that the concept is still deeply engrained in the teaching of chiropractic, ‘subluxation’ is a mystical entity or dogma which “is similar to the Santa Claus construct”, characterised by a “significant lack of evidence to fulfil the basic criteria of causation”. But even if chiropractic ‘subluxation’ were real, it would not be diagnosable with spinal x-ray investigations.
The inescapable conclusion from all this, I believe, is that the sooner chiropractors abandon their over-use of x-ray studies, the better for us all.