The gracilis muscle (GM) is located in the medial aspect of the thigh, medial and posterior to the long adductor in its proximal part. It originates at the pubic level and is inserted in the medial face of the tibia, in its upper part. As a functional free flap, it has been one of the most commonly used grafts in various reconstructions, such as penis, perineum, vagina, leg, brachial plexus, facial paralysis, rectal lesions, among others. Based on the above, the objective of this study was to complement the anatomy of the GM both in its dimensions and in its vascular pedicles and innervation, establishing the existing biometric relationships, contributing to the surgical anatomy, in its use as a graft. For this, 30 lower limbs of 20 bodies of adult, Brazilian, male, 14 right and 16 left individuals were used; 17 fixed in formaldehyde and 13 in glycerin. The thigh was divided into 4 quartiles listed from proximal to distal such as C1, C2, C3 and C4. The number of pedicles was counted and they were named as principal pedicle (PP), minor pedicle 1 (mP1), minor pedicle 2 (mP2) and minor pedicle 3 (mP3). The average length of the GM was 42.25 cm ± 2.35 cm and its average width was 32.90 ± 4.86 mm. With respect to vascular pedicles, a pedicle was found in 10/30 cases (33.3 %); one PP and one mP in 10/30 (33.3 %); one PP and two mP in 8/30 (26.7 %) and one PP and three mP in 2/30 (6.7 %). Its innervation always came from the anterior branch of the obturator nerve (aBON). The motor point was found at an average distance of 7.94 mm proximal to the entry of the PP in the GM. Biometric records are expressed in tables. The results obtained will contribute to anatomical knowledge, and can be used as morphological support for surgical procedures that involve the GM.
KEY WORDS: Anatomy; Gracilis muscle; Vascular pedicles; Innervation; Biometry.