Introduction. The superior transverse scapular ligament (STSL) links the margins of the suprascapular notch and converts it into a foramen, through which, the suprascapular nerve and, on some rare occasions, the suprascapular vessels pass. This conversion often results from partial or complete ossification of the STSL and may produce compressive symptoms in the suprascapular nerve. Material and Method. Twenty shoulders from human fetuses were dissected without the aid of optical instruments and, using a digital pachymeter of precision 0.01 millimeters, length measurements and thickness measurements were made. The fetal age was from 21 to 33 weeks of gestation, with a mean of weeks. Results. There was no statistically significant difference in STSL length or any difference in the thicknesses at the medial and lateral extremities between the halves of the body ( ). However, in the left half of the body, the medial extremity of the STSL was significantly thinner than the lateral extremity ( ). Conclusion. Anatomical and morphometric details about the STSL were described in human fetuses. These findings, in fetuses, may encourage the pursuit of further studies to understand the morphofunctional role and meaning of this small ligament. 1. Introduction The superior transverse scapular ligament (STSL) links the margins of the suprascapular notch. This ligament converts the notch into a foramen through which the suprascapular nerve and, on some rare occasions, the suprascapular vessels pass [1, 2]. This is the region where compression of the suprascapular nerve most commonly occurs [3, 4]. In adult humans, this conversion frequently results from ossification of the STSL, which may be partial or complete [5]. Variations in the morphology of the STSL and the suprascapular notch are among the best known factors predisposing towards the occurrence of compression of the suprascapular nerve [6]. There are several classification systems for the suprascapular notch [6–9], but little attention has been given to the morphology of the STSL [5, 6]. This knowledge is specifically important during arthroscopic or surgical procedures in the shoulder region [10, 11]. Our study had the aim of making a morphometric analysis on the STSL in human fetuses. 2. Material and Method Twenty shoulders from human fetuses were used (ten right and ten left, from nine males and one female). The fetuses belonged to the anatomy laboratory of the Federal University of Sergipe and had been obtained in accordance with Law 8501 of November 30, 1992, which deals with the use of unclaimed cadavers
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