The surgical anatomy of the superior gluteal nerve and anatomical radiologic bases of the direct lateral approach to the hip.

In view of the increasing popularity of the direct lateral approach to the hip joint for hemi- or total hip arthroplasty, the location of the superior gluteal nerve (SGN) was studied. This nerve is in danger when using a transgluteal incision. In 20 embalmed specimens the relation of the SGN to the tip of the greater trochanter (TT) was studied as well as the relation to the iliac crest. For this purpose macroscopy, microscopy and CT were used. In 13 hips a so-called most inferior branch was found at an average of 1 cm distal to the inferior branch, the main trunk of the nerve. There was substantial variation in the course of both the inferior and the most inferior branch of the SGN. In order to prevent nerve damage, proximal extension of the transgluteal incision should be limited to 3 cm cranial to TT. Furthermore the incision has to be confined to the distal one third of the distance TT-iliac crest. In tall people extra care should be taken.