3.1 Flashcards
Surface anatomy muscles
What bones make up the pectoral girdle?
clavicle and scapula
What bones make up the upper extremity?
Pectoral girdle: clavicle and scapula
Humerus
Radius
Ulna
Bones of the hand
Clavicle
Scapula
Overlies ribs 2-7
Humerus
Radius
Ulna
Radio-ulnar joints
- Interosseus membrane – syndesmosis joint between radius and ulna. Fiber direction allows forces traveling from hand to radius (e.g. falling onto outstretched hand) to be transferred to ulnar, which has a more stable articulation w/ humerus.
- Trochlear notch – hollowed area formed by coronoid process and olecranon that curves around trochlea of humerus at elbow joint
- Distal radioulnar joint – pivot joint; assists with supination and pronation motions
Label
Label
Label
Scaphoid Fracture
Most common and often misdiagnosed
Occurs after a fall on an outstretched hand
Can lead to poor blood supply to the proximal part of the scaphoid. Avascular necrosis may occur and produce degenerative joint disease of the wrist.
Colle’s Fracture
Complete transverse fracture of distal 2cm of the radius
Common in adults over 50, especially women because osteoporosis weakens bones
Results from forced extension of hand which occurs when falling on an outstretched arm
The distal fragment of the radius is pulled dorsally and superiorly, resulting in dinner fork deformity
Because of the rich blood supply to the distal end of the radius, bony union is usually good
Nerve innervation of the upper extremity
Brachial plexus
Terminal branches of:
- axillary n
- musculocutaneous n
- median n
- radial n
- ulnar n
Other branches that serve scapula and thorax:
- dorsal scapular n
- suprascapular n
- long thoracic n
Fractures of the humerus
- Humeral neck fractures endanger the axillary nerve and posterior circumflex humeral artery as they pass through the quadrangular space
- Humeral shaft fractures endanger the radial nerve and deep brachial artery as they lie within the radial groove
- Medial epicondyle fractures endanger the ulnar nerve as it passes posterior to the epicondyle
- Lateral epicondyle fractures endanger the radial nerve as it passes anterior to the epicondyle
Arterial supply
Subclavian a.
Axillary a., which changes to brachial a. at the lateral border of teres major
Brachial a. then bifurcates at the elbow forming the radial a. and ulnar a.
The radial and ulnar aa. for the palmar arch.
Deep brachial a.
branches from brachial a. and joins radial n. to enter posterior compartment of arm
Elbow anatomosis
ulnar collateral aa. branch and provide collateral circulation around the elbow; they anastomose with radial and ulnar recurrent aa.
Ulnar a
gives off common interosseous branch soon after it originates at the brachial a. bifurcation; it then splits into anterior and posterior interosseous aa. that run along the interosseous membrane
The radial and ulnar aa…
- Give off recurrent branches that help form the elbow anastomosis.
- Supply the forearm
- Contribute to the formation of palmar arterial arches that supply the hand.
Superficial Veins of Upper Limb
Cephalic v.
- begins radial and dorsal, wraps to ventral
Basilic v.
- ulnar and dorsal
- joint deep vv. to form axillary v.
Axillary v.
Medial cubital v. anastomosis
- cephalic and basilic
Axillary v.
Runs inferior to axillary a.
Is a continuation of basilic v.
Major tributaries:
- basilic v.
- cephalic v.
- brachial vv.
Axillary lymphatics
Superficial to lymph vessels and follow superficial vv.
Nodes:
- cubital
- axillary
- deltopectoral
Palmar arches
Superficial palmar arterial arch – formed largely by ulnar artery after entering hand through ulnar (Guyon’s) canal. The radial artery contributes via a superficial palmar branch. The arch is located just deep to the palmar aponeurosis.
Deep palmar arterial arch – formed largely by radial artery after passing posterior to the CMC joint of the thumb and through the anatomical snuffbox. The ulnar artery contributes some via a deep branch.
Common and proper palmar digital arteries branch from the superficial arch to supply the digits. The common palmar digital arteries are joined by branches of the deep arch thus forming an anastomosis between the 2 arches.
Princeps pollicis artery – branches from deep arch to supply thumb via 2 proper digital arteries
