Relative efficacy of clinical examination, electromyography, plain film radiography, myelography and lumbar phlebography in the diagnosis of low back pain and sciatica.

The procedures used in the investigation of low back pain and sciatica have been subjected to a double statistical analysis to determine their diagnostic accuracy, since contradictory opinions have been expressed in the literature. It was found that only lumbar phlebography was more accurate than the most simple procedure, the clinical examination. Myelography is more accurate than clinical examination only in making a positive diagnosis. In this case, it equals the reliability of lumbar phlebography, but so does plain film radiography which however leads to a positive diagnosis less constantly. Lumbar phlebography is the most accurate procedure for making a negative diagnosis, mainly by avoiding a false negative conclusion. A comparison is made with the statements in the literature and the complementary use of the different procedures is proposed for the investigation of low back pain and sciatica.