| scalenus anterior | <anatomy, muscle> Origin, anterior tubercles of transverse processes of third to sixth cervical vertebrae; insertion, scalene tubercle of first rib; action, raises first rib; nerve supply, cervical plexus. Synonym: musculus scalenus anterior, anterior scalene muscle, musculus scalenus anticus. (05 Mar 2000) |
|---|---|
| scalenus anterior syndrome | <syndrome> One of the precursors of disputed neurogenic thoracic outlet syndrome; a popular cause for upper extremity discomfort in the late 1930s and 1940s, based on the unproven concept that the lower trunk and brachial plexus and subclavian artery could be compressed in the intrascalene triangle by hypertrophic scalenus anticus muscle, the compression in turn affecting the nerves to it and setting up a vicious circle; this concept was essentially abandoned in the 1950s, when real causes, such as cervical radiculopathy and carpal tunnel syndrome, for upper extremity symptoms were appreciated, but resurrected in the 1980s, without attribution, as aetiology for upper plexus type of disputed neurologic thoracic outlet syndrome. (05 Mar 2000) |
| scalenus medius | <anatomy, muscle> Origin, costotransverse lamellae of transverse processes of second to sixth cervical vertebrae; insertion, first rib posterior to subclavian artery; action, raises first rib; nerve supply, cervical plexus. Synonym: musculus scalenus medius, middle scalene muscle. (05 Mar 2000) |
| scalenus posterior | <anatomy, muscle> Origin, posterior tubercles of transverse processes of fourth to sixth cervical vertebrae; insertion, lateral surface of second rib; action, elevates second rib; nerve supply, cervical and brachial plexuses. Synonym: musculus scalenus posterior, musculus scalenus posticus, posterior scalene muscle. (05 Mar 2000) |