Human Anatomy - Kotsan I. Y. 2009

Muscles and Fascia of the Upper Limb
Muscles of the Hand
Topography of the Upper Limb

The upper limb is divided into the following regions.

Shoulder regions (regiones brachii):

1) deltoid region (regio deltoidea), corresponding to the Location OF THE deltoid Muscle.

2) anterior brachial region (regio brachii anterior), corresponding to the contours of the biceps brachii muscle.

3) posterior brachial region (regio brachii posterior), corresponding to the middle PARTS OF THE triceps brachii muscle.

Elbow regions (regiones cubiti):

1) anterior cubital region (regio cubiti anterior), which includes the cubital fossa.

2) posterior cubital region (regio cubiti posterior).

Forearm regions (regiones antebrachii):

1) anterior forearm region (regio antebrachii anterior);

2) posterior forearm region (regio antebrachii posterior).

Hand regions (regiones manus):

1) palmar region (palm) of the hand (palma manus), corresponding to the palmar surface of the hand;

2) dorsal region (dorsum) of the hand (dorsum manus), corresponding to the dorsal surface of the hand (carpus and metacarpus).

In addition, the upper limb contains various fossae, apertures, sulci, and canals that house Blood Vessels and nerves, knowledge of which is essential for applied medicine.

The axillary fossa (fossa axillaris) is a depression on the body surface between the lateral thoracic wall and the Medial surface of the proximal arm. It is clearly visible when the arm is abducted. Beneath the Skin lining the axillary fossa and beneath the axillary fascia lies the axillary cavity.

The axillary cavity (cavitas axillaris) is shaped like a four-sided pyramid, with its base directed downward and its apex directed upward and medially. The axillary cavity has four walls: anterior, posterior, medial, and lateral. The anterior wall of the axillary cavity is formed by the pectoralis major and pectoralis minor Muscles; the posterior wall by the latissimus dorsi, teres major, and subscapularis muscles; the medial wall by the serratus anterior muscle; and the lateral wall by the biceps brachii and coracobrachialis muscles.

At its base, the axillary cavity opens through a wide aperture, the inferior aperture, the boundaries of which correspond to those of the axillary fossa. Between the clavicle anteriorly, the first rib medially, and the superior border of the scapula posteriorly lies the superior aperture (inlet) of the axillary cavity, which connects the axillary cavity to the neck region. The axillary cavity is filled with adipose tissue, Blood Vessels, nerves, and Lymph Nodes. Some vessels and nerves exit the axillary cavity through the triangular and quadrangular spaces in its posterior wall.

The triangular space (foramen trilaterum) is located more medially; its walls are formed superiorly by the inferior margin of the subscapularis muscle, inferiorly by the teres major muscle, and laterally by the long HEAD of the triceps brachii muscle. The circumflex scapular artery passes through this space.

The quadrangular space (foramen quadrilaterum) is located more laterally. Its lateral wall is formed by the surgical neck of the humerus, its medial wall by the long head of the triceps brachii muscle, its superior wall by the inferior margin of the subscapularis muscle, and its inferior wall by the teres major muscle. The posterior circumflex humeral artery and the axillary nerve pass through this space.

On the anterior region of the arm, along the sides of the biceps brachii muscle, lie two sulci: the medial and lateral bicipital sulci (sulcus bicipitalis medialis et sulcus bicipitalis lateralis). These sulci separate the anterior region of the arm from the posterior. The medial bicipital sulcus is more pronounced than the lateral one and is of greater practical significance. It contains the neurovascular bundle of the arm, which consists of the brachial artery, two brachial Veins, and the median nerve. In the event of bleeding from Branches of the brachial artery system, this vessel can be easily compressed within the medial bicipital sulcus.

Deep within the posterior brachial region lies the radial nerve canal, or humeromuscular canal (canalis n. radialis, s. canalis humeromuscularis), which is formed by the radial groove of the humerus covered superiorly by the triceps brachii muscle. The radial nerve and deep Vessels of the arm pass through this canal.

The cubital fossa is located in the anterior cubital region.

The cubital fossa (fossa cubitalis) is bounded superiorly by the brachialis muscle, medially by the pronator teres muscle, and laterally by the brachioradialis muscle. Superficial and deep blood vessels and nerves are situated within the region of the cubital fossa.

In the anterior region of the forearm, three sulci are distinguished: the radial, median, and ulnar sulci.

The radial groove (sulcus radialis) is situated between the brachioradialis muscle (laterally) and the flexor carpi radialis muscle (medially). It transmits the radial nerve, artery, and VEINS OF THE same name.

The median groove (sulcus medianus) lies between the flexor carpi radialis muscle (laterally) and the flexor digitorum superficialis muscle (medially). It transmits the median nerve.

The ulnar groove (sulcus ulnaris) is located between the flexor carpi ulnaris muscle (medially) and the flexor digitorum superficialis muscle (laterally). It transmits the ulnar nerve, artery, veins, and deep Lymphatic vessels.

Key Latin Terms

Deltoid muscle — m. deltoideus

Supraspinatus muscle — m. supraspinatus

Infraspinatus muscle — m. infraspinatus

Teres minor muscle — m. teres minor

Teres major muscle — m. teres major

Subscapular muscle — m. subscapularis

Coracobrachialis muscle — m. coracobrachialis

Brachialis muscle — m. brachialis

Biceps brachii muscle — m. biceps brachii

Triceps brachii muscle — m. triceps brachii

Anconeus muscle — m. anconeus

Brachioradialis muscle — m. brachioradialis

Pronator teres muscle — m. pronator teres

Flexor carpi radialis muscle — m. flexor carpi radialis

Palmaris longus muscle — m. palmaris longus

Flexor carpi ulnaris muscle — flexor carpi ulnaris

Flexor digitorum superficialis muscle — m. flexor digitorum superficialis

Flexor digitorum profundus muscle — m. flexor digitorum profundus

Flexor pollicis longus muscle — m. flexor pollicis longus

Pronator quadratus muscle — m. pronator quadratus

Extensor carpi radialis longus muscle — m. extensor carpi radialis longus

Short radial extensor muscle of wrist — m. extensor carpi radialis brevis

Extensor muscle of fingers — m. extensor digitorum

Extensor muscle of little finger — m. extensor digiti minimi

Ulnar extensor muscle of wrist — m. extensor carpi ulnaris

Supinator muscle — m. supinator

Long abductor muscle of thumb — m. abductor pollicis longus

Long extensor muscle of thumb — m. extensor pollicis longus

Short extensor muscle of thumb — m. extensor pollicis brevis

Extensor muscle of index finger — m. extensor indicis

Short abductor muscle of thumb — m. abductor pollicis brevis

Short flexor muscle of thumb — m. flexor pollicis brevis

Opponens muscle of thumb — m. opponens pollicis

Adductor muscle of thumb — m. adductor pollicis

Short palmar muscle — m. palmaris brevis

Abductor muscle of little finger — m. abductor digiti minimi

Short flexor muscle of little finger — m. flexor digiti minimi brevis

Opponens muscle of little finger — m. opponens digiti minimi

Lumbrical muscles — mm. lumbricales

Palmar interosseous muscles — mm. interossei palmares

Dorsal interosseous muscles — mm. interossei dorsales

Deltoid fascia — fascia deltoidea

Infraspinatous fascia — fascia infraspinata

Supraspinatous fascia — fascia supraspinata

Subscapular fascia — fascia subscapularis

Axillary fascia — fascia axillaris

Fascia of the arm — fascia brachii

Medial intermuscular septum of the arm — septum intermusculare brachii mediale

Lateral intermuscular septum of the arm — septum intermusculare brachii laterale

Extensor retinaculum — retinaculum extensorum

Flexor retinaculum — retinaculum flexorum

Fascia of the hand — fascia manus

Palmar aponeurosis — aponeurosis palmaris

Dorsal fascia of the hand — fascia dorsalis manus

Regions of the arm — regiones brachii

Deltoid region — regio deltoidea

Anterior region of the arm — regio brachii anterior

Posterior region of the arm — regio brachii posterior

Regions of the elbow — regiones cubiti

Anterior region of the elbow — regio cubiti anterior

Posterior region of the elbow — regio cubiti posterior

Regions of the forearm — regiones antebrachii

Anterior region of the forearm — regio antebrachii anterior

Posterior region of the forearm — regio antebrachii posterior

Regions of the hand — regiones manus

Palmar region (palm) of the hand — palma manus

Dorsal region (dorsum) of the hand — dorsum manus

Axillary fossa — fossa axillaris

Axillary cavity — cavitas axillaris

Trilateral space — foramen trilaterum

Quadrilateral space — foramen quadrilaterum

Medial bicipital sulcus — sulcus bicipitalis medialis

Lateral bicipital sulcus — sulcus bicipitalis lateralis

Radial canal (humeromuscular canal) — canalis n.

radialis, s. canalis humeromuscularis

Cubital fossa — fossa cubitalis

Radial sulcus — sulcus radialis

Median sulcus — sulcus medianus

Ulnar sulcus — sulcus ulnaris