Abstract: Objective　To observe and design the gluteal epithelial neurovascular flap pedicled with perforator of fourth lumbar artery, so as to provide anatomical and morphological basis for the clinical application.　Methods　Anatomical observation of 15 cases (30 sides) adult Chinese specimen of waist-hip region were performed. The distribution of posterior branch of the fourth lumbar artery, gluteal epithelial nerve and its subdivision branch were observed at the position of deep fascial perforation point. Measure The outer diameter of the posterior branch of the fourth lumbar artery, and the length of middle branch of the gluteal epithelial nerve were measured.  On the basis of applied anatomy, the gluteal epithelial neurovascular flap pedicled with perforator of fourth lumbar artery was designed and applied to repair huge wounds in sacrococcygeal tracts in 12 cases.　Results　The external diameter of the fourth lumbar artery's posterior branch penetrated the deep fascia was (1.16±0.43) mm, with 63.3% represented by single branches in 19 out of 30 instances. In 11 cases, the artery was divided into 2~3 branches before penetrating the deep fascia, accounting for 27.7%. The length of the intermediate branch of gluteal epithelial nerves was (147.82±16.37) mm. The design area of the gluteal fascial flap were the following  the superior boundary was 2~4 cm from the rotation point, the inferior boundary was the superior part of the gluteus maximus, the inside of superior boundary was the posterior median line, the lateral side was posterior axillary line. The flap size was 17.4 cm×12.5 cm~25.4 cm×18.3 cm.  Length-width ratio of the flap was (3~5): 1. Twelve cases of large sacrococcygeal wounds were repaired by the 4th lumbar artery perforated gluteal neurotrophic vascular flap. All the flaps survived and the effects were satisfactory.　Conclusions　The blood supply of the flap is mainly from the posterior branch of the fourth lumbar artery, the gluteal epithelial nerve and its branch innervation, which has certain regularity and predictability. This flap is easy to design, constant and clear anatomy, covers a large area, and is easy to operate, making it an ideal method for repairing huge wounds in the sacrococcygealgeal.

Key words: Gluteal epithelial neurovascular flap, Fourth lumbar artery, Anatomical observation; ,  Wound repair