Middle Scalene Muscle

The middle scalenus muscle (Musculus scalenus medius) is a muscle that is inserted into the anterior tubercle of the 2nd, 3rd, 4th, 5th and 6th cervical vertebra, as well as in the transverse process of the 7th cervical vertebra.

It is located behind the preceding muscle, reaching the transverse canal. The muscular body, originated by 6 tongues, are directed downwards and laterally. It is inserted into the upper side of the 1st rib behind the sulcus of the subclavian artery and emits a fascicle for the superoexternal side of the 2nd rib.

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