ABSTRACT
[Objective]To investigate the morphological characteristic of the scalenus minimus. [Methods]Totally 32(64 sides) embalmed adult cadavers were dissected and studied,the morphology of scalenus minimus and its relationship to brachial plexus was observed.Ten scalenus minimus were stained by HE to study membrane of the muscles.Twenty-seven(54 sides) embalmed adult cadavers were dissected carefully to investigate its nerve and blood supply.[Results]Scalenus minimus was found in 84.4% of cadavers(54/64).Its insertion was mainly composed of tendinous tissue,which was spaned by the lower trunk of brachial plexus.Scalenus minimus supply nerve branches was from ventral rami of the cervical seven root,and vascular supply was from:(1) branches of deep cervical artery,(2) branches of subclavia artery.[Conclusion]Scalenus minimus muscle,an independent but inconstant muscle,is existed in most people and sometimes responsible for compression of brachial plexus.It is suggested that scalenus minimus muscle should be resected carefully as well as scalenus anticus and medius during surgical treatment of thoracic outlet syndrome.