Pec, Axilla, Anterior Arm + Forearm And Palmar Hand Flashcards
Anatomical Position (thumb and palm)
Thumb is lateral
Palm is directed Anteriorly
Upper Limb Regions
Shoulder
Arm (Brachium)
Forearm (Antebrachium)
Hand
Pollex: thumb
Specific Regions Of The Upper Limb
Shoulder
Axillary Region
Arm
Cubical Fossa
Forearm
Wrist (carpal tunnel)
Hand
Digits: fingers/thumbAxillary region Boundaries
Bound by apex, base and 4 walls
Apex: cervico-axillary canal (bounded by the first rib, clavicle and superior edge of the scapula)
Base: skin and fat in axillary fossa (arm pit)
Muscle Compartments/Vessels/Innervation of the Arm
Muscles: anterior-flexors. Posterior-extensors
Vessels: anterior-brachial artery. Posterior-deep brachial artery
Innervation: anterior-musculocutaneous nerve. Posterior-radial nerve
Cubical fossa definition and boundaries
Triangular depression on anterior surface of elbow
Superior: Line from medial epicondyle to lateral epicondyle
Lateral: brachioradialis muscle
Medial: pronator teres muscle
Cubical Fossa Contents
End of brachial artery
Tendon of biceps brachii
Median nerve
Radial Nerve
Superficial vein that passes over: median cubital vein
Forearm muscle compartments/vessels/innervation
Muscles: anterior-flexors+pronators. Posterior-extensors+supinators
Vessels: anterior-radial+ulnar arteries. Posterior- posterior interosseous artery
Innervation: anterior-median and ulnar nerves. Posterior-radial nerve
The Carpal Tunnel
Tunnel between carpal bones (floor/walls) and flexor retinaculum (roof)
Contains: tendons of-flexor digitorum profundus, flexor digitorum superficialis and flexor pollicis longus.
Median nerve
Clinically relevant: pressure in tunnel can compress the median nerve
Relevant Bones in Upper limb
Clavicle, Scapula, Humerus, Radius, Ulna, carpals, metacarpals and phalanges
Hand Joints
carpometacarpal joint
Metacarpophalangeal joint
Proximal interphalangeal joint
Distal interphalangeal joint
Interphalangeal joint (thumb)
Anterior Chest Wall Muscles
Pectoralis Major (clavicular head and sternal head)
Mult. Heads allows it to perform several actions
Pectoralis minor
Subclavius
Muscles of the Lateral Chest wall
Serratus Anterior
Attaches to the entire anterior aspect of the medial border of the scapula. It’s the only protractor of the scapula. damage to this muscle or the nerve supplying it (long thoracic nerve) will lead to unopposed retraction of the scapula
Anterior arm Muscles
Biceps Brachii: long and short head (long head is lateral)
Coracobrachialis
Brachialis
Anterior Forearm Muscles
Proximal Attachment for most of the superficial muscles: distal end of the humerus (flexors on the medial and extensors in the posterior compartment attach to the lateral side)
Anterior Forearm Muscle Layers
1st: Pronator teres, Flexor Carpi radialis, Palmaris longus, Flexor carpi ulnars
2nd: Flexor digitorum Superficialis
3rd: flexor pollicis longus, flexor digitorum profundus
4th: pronator quadratus
Flexor digitorum superficialis vs. profundus
Distal attachment points of flexor digitorum superficialis are the shafts of the MIDDLE phalanges
Tendons split as they attach to the bone
Emerging from underneath these tendons are the tendons of the flexor digitorum profundus
BOTH muscles cross the PIP joint, both assist in flexing that joint. BUT the only muscle that crosses the DIP and thus flexes that joint is flexor digitorum profundus
Axillary Artery
Continuation of the subclavian artery
Subclavian artery becomes the axillary artery after it crosses the lateral border of the first rib
Axillary Artery divisions (3 segments)
TBH
Branches of axillary artery
Clinical correlation: the posterior circumflex humeral artery travels with the axillary never near the SURGICAL NECK of the humerus-a common site of fracture
Brachial Artery
After axillary artery crosses the inferior border of teres major muscle it becomes the brachial artery
Supply’s blood to the upper limb
Branches of the Brachial Artery
TBH
Ulnar and Radial Arteries
Brachial artery splits near the cubital fossa into ulnar (medial-pinky side) and radial (lateral-thumb side) branches
These 2 Arteries have several branches that anastomose with the branches coming off the brachial artery
Branches of the Ulnar and Radial Arteries
TBH
Veins
Most typically have the same name and travel with the Arteries
Only exception: superficial veins on the upper limb (no paired arteries)
Cephalic Vein
Travels along the lateral aspect of the forearm and arm, connecting to the axillary vein in the shoulder (runs upper outside aspect of the upper limb C for ceiling)
Basilic veing
Travels along the medial aspect of the forearm and arm. It pierces the brachial fascia in the middle of the arm and runs parallel to the brachial artery. It merges superiorly with deep veins in the arm to form the axillary vein
Runs lower inside portion of the upper limb B for basement
Median cubital Vein
Branch that connects the cephalic and basilic veins in the cubital region. Common site for venipuncture
Compartments of the Hand
Thenar Hypothenar Central Interosseous Adductor
Sheaths and Potential Spaces in the Hand
Sheaths: surround tendons and allow smooth movement (common flexor sheath and flexor pollicis longus sheath)
Potential Spaces: areas usually filled with CT Thenar space (1) Midpalmar space (2)
Sheaths, Spaces and Infection
Spaces and sheaths can be a source of infection (e.g. Tenosynovitis)
Infection can be contained by CT, but can also spread since some spaces and structures connect
Infection can spread from MIDPALMAR space through the carpal tunnel into the forearm
Infection in the 5th digital synovial sheath can spread to the common flexor sheath through the carpal tunnel into the forearm
Infection of the Flexor pollicis longus sheath can spread directly to the carpal tunnel and then into the forearm
Anatomical Snuff Box
Boundaries: medial-tendon of extensor pollicis longus
Lateral-tendon of extensor pollicis brevis, tendon of abductor pollicis longus
Contents: radial artery (pulse can be felt here) and scaphoid bone (forms the floor)
Muscles of the Palmar Hand
Adductor pollicis
Thenar muscles: abductor pollicis brevis, flexor pollicis brevis, opponents pollicis
Hypothenar muscles: abductor digiti minimi, flexor digiti minimi, opponents digiti minimi
Lumbricals
Palmar interossei
Dorsal interossei
Thenar muscles and innervation
Abductor pollicis brevis
Flexor pollicis brevis
Opponents pollicis
Innervation: median nerve (recurrent branch)
Hypothenar muscles and innervation
Abductor digiti minimi
Flexor digiti minimi
Opponents digiti minimi
Innervation: Ulnar nerve (deep branch)
Central muscles and innervation of palmar hand
Lumbricals and tends of FDS and FDP
Innervation?
Interosseous muscles and innervation
Palmar interossei (3) Dorsal interossei (4)
Innervation: ulnar nerve (deep branch)
Adductor muscles and innervation of palmar hand
Adductor pollicis
Ulnar nerve: deep branch
All muscles in the palmar hand are innervated by the ulnar nerve except 1/2 LOAF
1 and 2 lumbricals
Opponens pollicis
Abductor pollicis brevis
Flexor pollicis brevis
Arteries of the hand
Radial and ulnar arteries travel down the forearm on their respective side
Once they reach the wrist/hand, branches emerge that form arches in palmar region
Superficial palmar arch (artery)
direct continuation of the ulnar artery. The arch is formed with a superficial branch of the radial artery
Deep palmar arch (artery)
Direct continuation of the radial artery. The arch is formed with a deep branch of the ulnar artery
Proper Palmar Digital Arteries
Run along the sides of the fingers and are formed when each common palmar digital artery splits
Common Palmar Digital Arteries
Come off the superficial palmar arch
