A new approach to sciatic nerve block in the gluteal region

Two personal techniques of sciatic nerve block in the gluteal region were compared in a retrospective study. The study was carried out on 224 patients undergoing elective orthopaedic lower-limb surgery. The block was performed in 107 subjects with a modified Labat's technique, prolonging his line downwards to meet the surface projection of the sciatic nerve, according to Ellis and McLarry. In 117 patients the needle was inserted at the intersection of the hiatus-trochanteric line with a straight line joining the midpoint of the thigh with the posterior-superior iliac spine. The use of these landmarks improved paraesthesia elicitation and increased absolute success rate (66%). A dramatic drop in intra-operative supplemental analgesic and hypnotic needs was observed in these patients. Failure occurred in about 10% with both techniques, whilst side-effects were of minor importance. These results suggest that the new landmarks provide a more precise anatomo-clinical location of the sciatic nerve.