Ladder muscles

Scalene muscles - mm. scalenii Raise the upper ribs, acting as inhalation muscles. With fixed ribs, contracting on both sides, they bend the cervical spine, and with one-sided contraction - bend and rotate it to their side.

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Anterior scalene muscle - m.scalenus anterior

Origin: anterior tubercles of the transverse processes of the III - VI cervical vertebrae

Insertion: Tuberculum m. scaleni anterioris I rib

Innervation: spinal nerves C5-C7 - muscular branches of the cervical plexus

Diagnostics: The scalene muscles are distributed according to the frequency of their damage by myofascial trigger zones as follows: anterior, middle, posterior and least. TZ in the anterior scalene muscle are revealed by palpation of the muscle under the posterior edge of the lateral head of the sternocleidomastoid muscle, at the level of its intersection with the external jugular vein, which protrudes prominently under the skin when squeezed with a finger directly above the clavicle. A local convulsive response in the scalene muscles is rare. The presence of active trigger zones in the scalene muscles is always accompanied by point tenderness in the middle part of the subclavian fossa when pressing on it. This painful point, specific for damage to the scalene muscles, lies above the pectoralis minor muscle or slightly medial to it. Sometimes this painful point can be associated with the activity of trigger zones of the pectoral muscles. If the pectoral muscles are not affected, the painful point disappears immediately after inactivation of the trigger zones in the scalene muscles.

Referred pain: Active trigger points located in any of the scalene muscles may cause pain in the chest, arm, medial border of the scapula, and interscapular region. Areas of persistent dull pain in the breast area, shaped like two fingers, descending to the level of the nipple. The source of this pain pattern is usually trigger points located in the lower part of the middle scalene muscle or in the posterior scalene muscle. Referred pain in the anterior deltoid region with damage to the scalene muscles is not felt by patients deep in the joint, as is the case with damage to the infraspinatus muscle. The pain radiates lower along the anterior and posterior regions of the shoulder; then, without involving the elbow, it radiates to the radial part of the forearm, as well as to the thumb and index finger. The source of this pain pattern involving the arm are trigger points localized in the upper part of the anterior scalene muscle and in the middle scalene muscle. Pain in the superior antrum of the medial border of the scapula and in the adjacent interscapular region is usually caused by trigger zones localized in the anterior scalene spine.

Middle scalene muscle - m. scalenus medius

Origin: transverse processes of I (II) - VII cervical vertebrae

Insertion: 1st rib, posterior to Sulcus a. subclaviae

Innervation: spinal nerves C3-C8 - muscular branches of the brachial plexus

Diagnostics: The middle scalene muscle lies deep, in front of the free edge of the upper bundles of the trapezius muscle. When palpating, it can be pressed against the posterior tubercles of the transverse processes of the cervical vertebrae.

Referred pain: see above

Posterior scalene muscle - m. scalenus posterior

Origin: posterior tubercles of the transverse processes of the V(VI) - VII cervical vertebrae

Attachment: 2nd rib

Innervation: spinal nerves C7-C8 - muscular branches of the brachial plexus

Diagnostics: The posterior scalene muscle is poorly accessible to palpation. It lies behind the middle scalene muscle and its fibers are directed more horizontally than the fibers of the latter. To facilitate palpation of the posterior scalene muscle, the levator scapulae muscle, which lies above it, is shifted to the side where it emerges from under the anterior free edge of the upper bundle of the trapezius muscle.

Referred pain: see above