Anatomy 534 Superficial Back PDF

Anatomy 534 Superficial Back 50 Muscles of the Back - there are 3 groups of muscles in the back: - superficial - intermediate - deep...

Anatomy 534 Superficial Back 50 Muscles of the Back - there are 3 groups of muscles in the back: - superficial - intermediate - deep - the superficial and intermediate muscle groups are considered to be extrinsic - that is muscles of the back that deal primarily with: - limb movement (the superficial group) - respiration (the intermediate group) superficial modperius I. The Superficial Group: Add - these muscles are extrinsics dealing with upper limb int aaehEiiiiii together rotation. bring and - there are two layers in the superficial muscle group iy YAMASAKI.fi f that function in connecting esea the upper limb to the trunk: A. Superficial Extrinsics i) Trapezius attaches the pectoral girdle to the skull and vertebral column. It assists in suspending the TEEE.hgqp.fi upper limb. It is Rhomboimdasor innervated by CN XI (accessory nerve) and exhibits three groups of fibers: - superior fibers elevate the vertebral scapula bodies - middle fibers adduct the zfg.de scapula - inferior fibers that depress and adduct the scapula. ii) Latissimus dorsi a tendon  Anatomy 534 Superficial Back 51 is another large fan-shaped muscle that covers the inferior part of the back from roughlyT6 to the iliac crest. It passes between the trunk and attaches to the floor of the intertubercular groove on the humerus. It acts directly on the shoulder joint and indirectly on the pectoral girdle. It is innervated by the thoracodorsal n. It extends, adducts and medially rotates the humerus. B. Deep Extrinsics i) Levator scapulae attaches to the posterior tubercles of the transverse processes of C1-4 and the vertebral (medial) border of the scapulae. It assists the trapezius in elevating the scapulae as well as maintaining its level. It is innervated by the dorsal scapular n. ii) Rhomboid major and minor lie deep to the trapezius forming parallel bands that pass inferolaterally from the vertebrae to the medial border of the scapula. The major is generally twice as wide as the minor. Both rhomboids brace back the shoulders by retracting the scapula, as well as elevate and maintain its level and fix it to the thoracic wall. They are also innervated by the dorsal scapular n. and the 3rd and 4th cervical nn. The remainder of the muscles of the back; the intermediate layer (extrinsics) and deep layer (intrinsics) and will be covered in the section on the trunk. or attachments Not concernedby innervation