The relation of the nerves with the piriformis muscle in the deep gluteal region examined in 50 buttock from 18 male and 7 male newborn cadavers. The nerves were found in usual position in 74% of sides, while one or more nerves perforated the piriformis in 16% and, unusual location of the nerves with intact piriformis was in 10% of sides. Abnormal located nerves are utilised in view of whether originating from dorsal or ventral part of the sacral plexus.