Interval 7: Axilla, Arm, Thigh Flashcards
(117 cards)
Main (general) functions of the pectoral girdle
-connect upper limb to axial skeleton
5 muscles clavicle provides attachment for
Pectoralis major Deltoid Trapezius Sternocleidomastoid Subclavius
________ is the first bone in the body to ossify.
- Clavicle
- Has both intramembranous and endochondral modes of ossification
T/F: Clavicle is a long bone so it therefore has a medullary cavity
-False; it is a long bone but it lacks a medullary cavity
The clavicle is the most frequently broken bone in the body. In particular, which part of the bone is the weakest?
- Junction of its medial 2/3s and lateral 1/3
- also the point where medial and lateral curvatures meet
Why is “separation of the shoulder” following tearing of the acromioclavicular and/or coracoclavicular ligaments a misnomer?
-It is the acromio-clavicular joint which is separated and not the shoulder joint
4 muscles that connect the upper limb to the anterior and lateral thoracic wall
- Pectoralis major
- Pectoralis minor
- Serratus anterior
- Deltoid
Functions of Pectoralis Major
-Major flexor, adductor, and medial rotator of the arm
Functions of pectoralis minor
-protracts, depresses, and stabilized the scapula against thoracic wall
Serratus anterior functions
- protracts and rotates scapula
- stabilizes medial border of scapula against the thoracic wall
Innervation of serratus anterior
-long thoracic nerve
-Deltoid functions
-can flex, extend, or abduct the arm depending which fibers activates
Innervation of anterior compartment of arm vs posterior compartment
- Anterior: musculocutaneous nerve
- Posterior: radial nerve
3 muscles of arm anterior compartment and 1 muscle of posterior compartment of arm
-Anterior: Biceps branchii. Brachialis, Coracobrachialis
Posterior: Triceps Brachii
Biceps brachii function
- flexion of arm
- flexion and suppination of forearm at elbow joint
Brachialis function
-flexion of forearm at elbow
Coracobrachialis function
-flexion of the arm
Triceps brachii function
-major extensor of the arm and forearm
Upper limb is innervated by the brachial plexus, which is formed by an intermingling of ventral rami from the ________ spinal nerves
-C5-T1
Erb-Duchenne Syndrome results from a lesion of what?
-C5 and C6 ventral rami of the superior trunk of the plexus
What musculature is usually affected in Erb-Duchenne Syndrome?
- proximial musculature in the upper limb
- muscles acting at the shoulder and elbow
What infamous position will the upper limb reside in in Erb-Duchenne Syndrome?
- “waiter’s tip position”
- results from a loss of abduction and a weakness of flexion and lateral rotation at glenohumeral joint
- the arm is adducted, extended, and medially rotated
T/F: Rhomboid muscles, levator scapulae muscle, and the serratus anterior muscle are affected in Erb-Duchenne Syndrome.
False; they are unaffected because the nerves that supply these muscles arise from ventral rami proximal to the lesion
Klumpke’s Paralysis results from?
-Compression of the C8 and T1 VR in the inferior trunk of the plexus