Blood Flow of the Gluteus Medius.

Weakness of the hip abductor muscles caused by wide surgical dissection may produce a Trendelenburg gait postoperatively, and increase disability of the postoperative hip. We investigate the dissection-effect of the gluteus medius muscle to its blood flow using an in vivo animal model.Sixteen hips of 8 adult rabbits were used. Blood flow was measured using the hydrogen washout technique. After the control blood flow rate was determined, the origin of the gluteus medius muscle was dissected from the iliac crest in the proximal-distal direction in 10 hips. Blood flow of the gluteus medius muscle was measured every one-third of the dissection. In the other 6 hips, the greater trochanter was osteotomised and the gluteus medius muscle dissected from the ilium in the distal-proximal direction. Blood flow of the gluteus medius muscle was measured every one-third of the dissection.Results showed that the blood flow was decreased significantly from control value after dissection of the proximal or distal two-thirds of the gluteus medius musie from its origin. It is suggested that minimum damage to the mid-portion of the gluteus medius muslcle is important to reduce the incidence of postoperative complications.