A case of large scalenus minimus muscle.

During the dissection of an 80-year-old, white, male cadaver, a large scalenus minimus muscle was detected on the right side. Scalenus minimus muscle, a fiber bundle which strengthens the suprapleural membrane, arises from the anterior tubercle of the transverse process of the 7th cervical vertebra, and inserts to the inner border of the first rib and cupula pleura. In the present case, the scalenus minimus muscle on the suprapleural membrane was large on the right side. Its origin was on the anterior tubercle of the transverse process of the 7th cervical vertebra, and the muscle was located between the C7 and C8 anterior rami. The present case is noteworthy because of its great dimension and relation with the brachial plexus. Apart from its importance in cervical region anesthesia and surgery, such an anatomical structure can lead to several clinical conditions both by spasm and compression such as neurogenic thoracic outlet syndrome.