Diagnostic value of history and physical examination in patients suspectedof sciatica due to disc herniation: a systematic review

We conducted a systematic review of the literature from 1965-1994 to assess the value of history and physical examination in the diagnosis of sciatica due to disc herniation; we also included population characteristics and fe atures of the study design affecting diagnostic value. Studies on the diagn ostic value of history and physical examination in the diagnosis of sciatic a due to disc herniation are subject to important biases, and information o n numerous signs and symptoms is scarce or absent. Our search revealed 37 s tudies meeting: the selection criteria; these were systematically and indep endently read by three readers to determine diagnostic test properties usin g a standard scoring list to determine the methodological quality of the di agnostic information. A metaanalysis was performed when study results allow ed statistical pooling. Few studies investigated the value of the history. Pain distribution seemed to be the only useful history item. Of the physica l examination signs the straight leg raising test was the only sign consist ently reported to be sensitive for sciatica due to disc herniation. However , the sensitivity values varied greatly, the pooled sensitivity and specifi city values being 0.85 and 0.52, respectively. The crossed straight leg rai sing test was the only sign shown to be specific; the pooled sensitivity an d specificity values were 0.30 and 0.84, respectively. There was considerab le disagreement on the specificity of the other neurological signs (paresis , sensory loss, reflex loss). Several types of bias and other methodologica l drawbacks were encountered in the studies limiting the validity of the st udy results. As a result of these drawbacks it is probable that test sensit ivity was overestimated and test specificity underestimated.