serratus anterior muscle
Serratus anterior muscle arises from the anterolateral chest wall as eight interdigitations of muscle that run posteriorly around the chest wall, under the scapula to insert onto the medial scapula. It is considered one of the four muscles of the pectoral region.
- origin: anterolateral ribs 1-8 or 1-9
- insertion: medial border of the scapula
- innervation: long thoracic nerve
- draws scapula anteriorly against the chest wall
- when scapula is fixed, assists in respiration
Injury to the long thoracic nerve during axillary surgery causes winging of the scapula as serratus anterior no longer holds the scapula against the chest wall.
- attachment to the 10 rib
- absence of attachments to the 1 rib
- union with fibers of the insertion of the levator scapulae, external intercostal or external oblique muscles
- Elastofibroma dorsi
- Musculus serratus posterior superior
- Musculus serratus posterior inferior