Connecting the first and second ribs up into each side of the neck, the scalenes are a set of three lateral vertebral muscles, the scalenus medius, scalenus anterior, and the scalenus posterior. Derived from the Greek word, ‘scalenos’, which means ‘uneven’ each is a different length.
The first two act together to increase the height of the first rib, tilt the head in the same direction, and permit the head to move side to side. The third, the scalenus posterior, raises the height of the second rib, and to a small degree, bends and rotates the neck. Acting in this manner, the scalenes provide breathing support.