The significance of medical imaging findings in low back pain

An investigation was conducted of 213 low back pain patients attending a specialized clinic, in order to assess the diagnostic value of medical imaging. The majority of these patients were in the working age groups of 31-50 years and 63.8 per cent were men. Of the total study population, 116 patients (54.5 per cent) had no potentially causative medical imaging findings. In the remaining 97 patients the most commonly seen abnormal imaging picture pointed to intervertebral disc herniation, noted in 62 individuals. Of these, 'post-surgical deterioration' was reported in 33 patients, being 15.5 per cent of the total of 213 subjects. Patients with imaging demonstrable disc herniation and clinical as well as electro-physiological neurological deficit had the briefest duration of low back pain and were in the youngest age group. Degenerative changes of the facet joints were found in 36 patients (16.9 per cent). They were mostly unisegmental, either as a single finding or superimposed upon spondylolisthesis or at the level of a previous operation on the lumbar spine. Spondylolisthesis was observed in 19 patients, being 8.7 per cent of the 213 low back pain patients or 19.6 per cent of the 97 individuals with positive imaging findings. Medical imaging signs of Grade III degenerative spondylarthritis were rarely seen. Considering these findings and the high proportion of 'idiopathic' low back symptoms we conclude that our imaging tools are still inadequate for diagnostic purposes and provide little prognostic benefit. It appears that there is also undue reliance being placed on imaging findings leading at times to the prescription of treatments with the potential of promoting chronicity and deconditioning, thus possibly further harming the patient.