Effect of Posterior Femoral Cutaneous Nerve Block on Postoperative Posterior Lateral Knee Analgesia in Patients With TKA

All nerve blocks were performed under ultrasound guidance，single supragluteal approach sciatic nerve block using a nerve stimulator, 20 ml of drug was injected around the sciatic nerve, the extent of drug diffusion was observed, the needle tip was turned into the deep surface of the gluteus maximus muscle below the deep gluteal artery and 5 ml of drug was injected, followed by a retractile canal saphenous nerve block injected with 15 ml of drug, and the difference in sensation of the posterior thighs of the bilateral thighs was measured after 15 min to ensure posterior femoral cutaneous nerve were blocked

All nerve blocks were performed under ultrasound guidance，single subgluteal approach sciatic nerve block using a nerve stimulator, with 25 ml of drug injected around the sciatic nerve, followed by a retractile canal saphenous nerve block with 15 ml of drug injection