functional organizations of the arm and hand Flashcards
compartments
each contains one or more functional groups of muscles, deep fascia divides the arm and forearm into post and ant components
anterior/flexor compartment of arm
contains muscles that flex the elbow joint and supinate the radioulnar joint
posterior/extensor compartment of arm
contains muscles that extend the elbow joint
innervation of anterior compartment of arm
musculocutaneous: from lateral cord of the brachial plexus. C5-C7, C6 is the main contributor. Motor innervation to muscles in the anterior brachial compartment and carries sensory from the lateral portion of the forearm (C6 dermatome)
innervation of posterior compartment of arm
radial nerve: derived from pot cord of brachial plexus, C5-T1, C5-7 are the main contributors. Motor to triceps and anconeus, sensation from post lat portion of arm (C5 dermatome)
anterior compartment of the forearm
contains muscles that flex the wrist joint, pronate the radioulnar joint and flex the digits
posterior compartment of the forearm
contains muscles that extend the wrist joint, supinate the radioulnar joint, and extend and abduct the digits
innervation of the posterior compartment of the forearm
radial nerve
innervation of the anterior compartment of the forearm
ulnar and medial nerve
transition zones (3)
provide a passageway for the contents (particularly nerves and vessels) of one compartment to enter another 1. axilla 2. cubital fossa 3. wrist
muscles in the anterior compartment of the arm (3)
- biceps brachii 2. brachialis 3. coracobrachialis
blood supply to muscles in ant compartment of arm
brachial artery, branches include: 1. muscular branches to the muscles in the ant compartment of the arm 2. collateral branches in elbow anastomosis 3. deep brachial artery: extensor compartment
Muscles in the post compartment of the arm (2)
- triceps brachii 2. anconeus
Blood supply of the posterior compartment of the arm
Deep profunda brachial artery (1st brach of the brachial) gives off: -muscular branches to the muscles in the extensor compartment -collateral branches in elbow anastomosis
Veins in the arm (3)
Cephalic (lateral) Basilic (medial) Median cubital (connects the 2)
Biceps rupture
could tear the biceps from an attachment on the supraglenoid tubercle, the radial tuberosity or both. Make the bicep appear higher or lower on the arm depending on where it is torn. Sometimes if the person is not an athlete they won’t repair it, if they do, they sew the tendon back onto the bone
Cubital Fossa
region anterior to the elbow joint, passageway for nerves and vessels traveling from the arm into the forearm, venipuncture usually performed here
Cubital Fossa Boundaries
Superior: imaginary line connecting condyles Medial: pronator teres lateral: brachioradialis roof: skin, fascia, bicipital apaneurosis floor: medial: brachilis lateral: supinator
Cubital Fossa Contents (4ish)
- radial nerve 2. biceps tendon 3. brachial artery and vein terminal branches: radial and ulnar artery 4. median nerve