Lecture 2: Cubital fossa and forearm muscles

Lecture 2: Muscular System Cubital
Fossa and Forearm Muscles
Upper arm
Forearm
Anterior compartment
 Consists of 8 muscles: innervated by the median and ulnar nerves
 Divided into 3 muscle groups
 Superficial (4 muscles)
 Intermediate (1 muscle)
 Deep (3 muscles)
Forearm (anterior)
Superficial group
1. Pronator teres
 Origin: medial epicondyle and coronoid process of the ulna
 Insertion: the lateral aspect of the radial shaft
 Action: flexion and pronation
 Innervation: median nerve
2. Flexor carpi radialis
 Origin: medial epicondyle
 Insertion: base of the 2nd and 3rd metacarpals
 Action: stabilisation of the wrist and flexion of the wrist and elbow
 Innervation: median nerve
3. Palmaris longus
 Origin: medial epicondyle
 Insertion: Palmar aponeurosis
 Action: Tenses palmar fossa
 Innervation: median nerve
4. Flexor carpi ulnaris
 Origin: medial epicondyle and coronoid process of the ulna
 Insertion: pisiform by the pisihamate and pisimetacarpal ligaments
 Action: flexion and adduction of the wrist
 Innervation: ulnar nerve
Intermediate group
1. Flexor digitorum superficialis
 Origin: medial epicondyle, radius and coronoid process of the ulna
 Insertion: base of the middle phalanges of the 4 medial fingers
 Action: flexion of the joins that the tendons pass
 Innervation: median nerve

, Deep group
1. flexor digitorum profundus
 Origin:
3
 Upper of the anterior and medial surfaces of the ulna shaft
4
 Interosseous membrane
 Insertion: base of the distal phalanges of the 4 medial fingers
 Action: flexion of the joints that the tendons pass
 Innervation: median (laterally) and ulnar (medially) nerves
2. Flexor pollicis longus
 Origin: upper anterior surface of the radial shaft
 Insertion: distal phalanx of the thumb
 Action: flexion of the thumb and wrist
 Innervation: median nerve
3. Pronator quadratus
 Origin: distal surface of anterior and medial aspects of the ulna shaft
 Insertion: the distal surface of the anterior and medial aspects of the radial shaft
 Action: pronation
 Innervation: median nerve

Cubital fossa
 Transitional zone between the brachium and the antebrachium
 Inverted triangle by the elbow that is covered by skin and fascia
 Base: imaginary lines between the epicondyles
 Lateral border: medial border of the brachioradialis
 Medial border: lateral border of the pronator teres
 Roof: skin, fascia, superficial nerves and vessels
 Floor: brachialis and supinator muscles
 Contents
 Biceps brachii tendon Muscle
 Brachial artery Artery
 Median nerve
 Carpal tunnel
Nerve
 Flexors of the digits enter the carpal tunnel
 Formed by the medial and lateral carpal pillars
 Completed by the flexor retinaculum
 Carpal tunnel syndrome
 Inflammation of the tendons
 Impingement of the median nerve