[Electromyographic findings in the gluteal muscles in the Watson-Jones and the Bauer surgical approaches to the hip joint].

The authors have made electromyographic examination of m. tensor fasciae latae and m. glutaeus medius and sometimes also minimus in patients after the implantation of total endoprosthesis of the hip joint by anterolateral Watson - Jones approach and transgluteal Bauer approach with the aim to find out if there occurs the anticipated transection of n. glutaeus usp. and dennervation of m. tensor fasciae latae and compare from this viewpoint both approaches. The examination was performed in 18 patients after the implantation of 20 total endoprostheses of the hip joint (out of which 10 hip joints were operated on by Watson - Jones approach and 10 by Bauer approach) in the period of 6-20 weeks after operation. In the examination concentric needle electrodes and NEUROMATIC 2000 C device (produced by DANTEC Co.) were applied. It was found out that the transection of n. glutaeus sup. is inevitable in neither approach. In patients operated on by Watson-Jones approach there occurred only twice complete transection of the nerve with the dennervation of m. tensor fasciae latae, six time incomplete interruption of the nerve and twice the finding in m. tensor fasciae latae was normal. In patients operated on by Bauer approach complete transection of n. glutaeus sup. was found out six times and incomplete interruption of this nerve four times. Thus from this viewpoint Watson-Jones approach is more considerate. Moreover, in Bauer approach eight times there occurred partial interruption of the innervation of the ventral portion of m. glutaeus medius. Consequently, the study has not proved the assumption that both approaches must necessarily result in complete transection of n. glutaeus sup.(ABSTRACT TRUNCATED AT 250 WORDS)