Pectoalis major & minor, serratus anterior, subclavius, levatore scapulae, rhomboideus minor & major, and trapezius

Muscles of Upper Arm and Shoulder  Pectoralis major and minor:  Major: large fan-like  Originates sternum and clavicle  Inserts in humerous (shoulder)  Elevates sternum  Minor:  Originates ribs 2-5  Insert in caracoid process of scapula  Deep to pectoralis major

Muscles of Upper Arm and Shoulder  Serratus anterior:  Originate ribs 1-9  Insert in scapula  Subclavius:  Originates clavicle  Insert in first rib  Levator scapulae:  Originate C1-C4  Insert in scapula

Muscles of Upper Arm and Shoulder  Rhomboideus major and minor  Major:  Originate T2-T5  Insert in scapula  Minor:  Originate C7 and T1  Insert in scapula  Provide stability for shoulder girdle

Muscles of Upper Arm and Shoulder  Trapezius:  Originate from C2-T12  Insert into scapula and clavicle  Generally, accessory muscles support and protect thoracic cavity.

Review  Inspiration muscles:  Primary:  Diaphragm  Accessory:  Muscles of thorax: anterior and posterior  Muscles of neck  Muscles of upper arm and shoulder

Muscles of Thorax, Back, and Upper Limbs Abdominal Muscles

Anterior and Posterior

Anterior  Internal intercostals:  Origination ribs 2-12  Insert ribs 1-11  Deep to external intercostals  Innermost intercostals:  Same origination and insertion as internal intercostals.  Deepest intercostals  Not found in chondral portion

Anterior  Transversus thoracis:  Originates on sternum  Inserts in ribs 2-6

Subcostals and Serratus posterior inferior

Posterior  Subcostals:  Run parallel to internal intercostals  May span more than one rib  Serratus posterior inferior:  Originates on T11-L3  Inserts in ribs 7-12

Anterolateral and Posterior Muscles

Anterolateral  Transversus abdominis:  Deepest of the anterior abdominal muscles  Originates from vertebral column  Inserts in aponeurosis, ribs 6-12, and pubis  Internal oblique abdominis:  Originates from pelvic girdle  Inserts in lower ribs and aponeurosis

Anterolateral  External oblique abdominis:  Most superficial and largest  Originate ribs 5-12  Insert in pelvic girdle and etc.  Rectus abdominis:  Originate pubis  Insert sternum and ribs  “six pack”

Posterior  Quadratus lumborum:  Originate from pelvic girdle  Insert in lumbar vertebrae

Latissimus dorsi

Upper Limb  Latissimus dorsi:  Originates from lower vertebrae  Insert into humerous  Role in expiration only suspected

Review  Inspiration  Diaphragm and accessory  Expiration  Thoracic and abdominal