Arm And Anterior Forearm Flashcards
Organization of upper limb
. Arm (brachium)
. Forearm (antebrachium)
. Wrist (carpus)
. Hand
Brachial fascia
Deep fascia of arm
Antebrachial fascia
Deep fascia of forearm
Medial and lateral intermuscular septa
Extensions of deep fascia that attach to medial and lat. suracondylar ridges of the humerus and shafts of radius and ulna
Retinacula
. Thickenings of antebrachial fascia that attach to distal radius and ulna and carpal bones
. Form osseofibrous tunnels for tendons of the forearm muscles
. Prevents bowstringing
Synovial tendon sheaths
. Thin walled, fibrous sacs lined w/ synovial membrane and lubricated by synovial fluid
. reduce friction and allow tendons to slide smoothly beneath retinacula
Compartments of arm and how they’re separated
. Ant. And post. Compartments separated by shaft of humerus and med. and lat. intermuscular septa
Forearm compartments and how they’re separated
. Ant. And post. Compartments separated by shafts of radius and ulna, interosseous membrane, and the med. and lat. intermuscular septa
Anterior compartments muscles
. Flexors and pronators
. Innervated by nerves derived from ant. Divisions (med/lat cords) or brachial plexus
Posterior compartment arm muscles
. Extensors and supinator
. Innervated by nerved derived from post. Division of brachial plexus
Dermatome distribution in arm
. Distributed along pre and postaxial borders of upper extremity in pattern that reflects limb’s origin in lateral body wall
. Single dermatome supplied by several peripheral nerves and individual named nerves carry fibers from several fiber segments
Autonomous area (zone)
. Region of skin supplied by single spinal nerve w/o any overlap
Myotome distribution
. Along proximodistal axis of extremity . C5-6 supply shoulder . C6-7 supply elbow . C7-8 supply wrist . C8-T1: supply hand
Anconeus OIAN
O: lat. epicondyle of humerus
I: lat. surface of olecranon process of ulna
A: weakly extends forearm and stabilizes elbow joint
N: radial n.
Deep tendon reflex of biceps brachii mediated by —
C5 and C6 spinal levels
Triceps brachii reflex mediated by ___
C7
Anterior component of arm artery
Brachial artery
Posterior compartment of the arm arteries
Branches of profunda brachii a.
Pronator teres m OIAN
O: Medial epicondyle of humerus, coronoid process of ulna
I: Lateral radius at midshaft
A: Pronates forearm
N: Median n.
Flexor carpi radialis OIAN
O: Medial epicondyle of humerus
I: Base of Metacarpal II
A: Flexes and abducts wrist
N: Median n.
Palmaris longus m. OIAN
O: Medial epicondyle of humerus
I: Palmar aponeurosis
A: Weakly flexes wrist
N: Median n.
T/F palmaris longus is missing in over 10% population
T
Flexor carpi ulnaris OIAN
O: Humeral head—medial epicondyle of humerus
Ulnar head—medial olecranon process, posterior border of ulna
I: Pisiform bone, hook of hamate bone, and base of Metacarpal V
A: Flexes and adducts wrist
N: Ulnar n.
Flexor digitorum superficialis m. OIAN
O: Humeroulnar head: medial epicondyle, coronoid process of ulna, Radial Head: proximal ant. surface of radius
I: By 4 separate tendons to bases of middle phalanges of Digits II-V
A: Flexes PIP, MP, and wrist joints
N: Median n.
Muscles in anterior compartment superficial layer
. Pronator teres . Flexor carpi radialis . Palmaris longus . Flexor carpi ulnaris . Flexor digitorum superficialis
Deep layer muscles of ant. Compartment of the forearm
. Flexor digitorum profundus
. Flexor pollicis longus
. Pronator quadratus