[Usefulness of cerebrospinal fluid in patients with sciatica].

The authors report the data of the analysis in cephalo-rachidial fluid during 162 sciaticas. 52,5% cases have a normal albuminorachidia. There is a correlation between the clinical findings bur none with the evolution before punction and the albuminorachia. When it is found more than 0,40 g/l there are abnormalities on the myelographic-examination and the patients are more often operated on. In fact the analysis of the cephalo-rachidial fluid is not very useful in common sciaticas. It is necessary to follow up cases where more than five cells (by mm3) are found because they might become multiple sclerosis (3 cases one year later). A determination of the beta-2-microglobulin was performed because it is an excellent criteria of inflammation, in the cephalo-rachidial fluid. During sciatica its level is regularly normal (24 normal over 30); but is may increase in other pathological situations which, at the beginning, look like sciaticas.