The scalenus posterior, additionally known as the posterior scalene, is the smallest of the scalene muscle mass within the neck. There’s a posterior scalene on both sides of the neck. These muscle mass transfer the neck and the second rib.
Every scalenus posterior muscle connects the decrease two cervical vertebrae (of the neck) to the second rib. They insert onto the posterior-lateral floor of the rib, which implies they connect to the again of the aspect of the bone.
The scalenus posterior flexes the cervical vertebrae when it acts unilaterally (with solely considered one of its pairs of muscle mass working). This strikes the pinnacle ahead, as would possibly happen when one is nodding. It additionally flexes the neck and raises the second rib when it acts bilaterally (when each posterior scalene muscle mass are working). The second rib is raised throughout inspiration, or inhaling. The scalenus posterior works with the longus capitis, longus colli, scalenus medius, and the scalenus inside muscle mass.
Its nerve provide contains the posterior branches C5, C6, C7, and C8. Damage to the scalenus posterior could end in scalenus anticus syndrome (additionally known as thoracic outlet syndrome). This ends in ache within the chest, shoulders, again, and arms. In excessive circumstances, the scalenus posterior could lower blood circulation to the arms, making them numb and chilly. Scalenus anticus syndrome could also be handled via myofascial launch — a particular sort of tissue therapeutic massage remedy — and neck adjustment by a chiropractor. Such therapy could relieve strain on the nerves and blood vessels by lowering the stress within the muscle mass and irregular movement of the neck.