FASCIA (divisions)- Superficial (Hypodermis, Subcutaneous

Tissue)- Deep

o Derivatives1. intermuscular septa2. ligaments3. tendons4. aponeurosis5. muscular and nervous

investmentso Receives different names according to

region1. Pectoral Fascia – encloses

pectoralis major.2. Clavipectoral Fascia – encloses

subclavius and pectoralis minor. 3. Axillary Fascia4. Brachial Fascia – arm5. Antebrachial Fascia – forearm6. Palmar Fascia7. Dorsal Fascia8. Flexor and Extensor Retinacula9. Digital Fibrous Flexor Sheaths

UPPER LIMB (divisions)- Joints divide the superior appendicular

skeleton - Limb is divided into 4 main regions (bold)

o Shoulder (pectoral)o Arm (brachium)o Elbow (cubitum)o Forearm (antebrachium)o Wrist (carpus)o Hand

BONES OF UPPER LIMB

Legend: C- Scaphoid, D- Lunate, E- Triquetrum, F-Psiform, G- Trapezium, H- Trapezoid, I-Capitate, J-Hamate, L- Radius, L1-Styloid process of the Radius, M- Ulna, M1- Styloid process of the Ulna

BONY LANDMARKS (parts that can be palpated- all areas in green)

Anterior

Fyi- clavicle is the first long bone to ossify in fetus

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Pectoral girdle

Clavicle

Scapula

Humerus

Radius

Ulna

Carpals (8)Metacarpals (5)

Phalanges (ptoximal- 5, middle- 4, distal -5)

Muscle and Fascia Compartments of the Upper Limb

Dr. Adelia Matanguihan- Quijano M.D.

1 July 2009

Posterior

MUSCLES OF THE PECTORAL REGION1- Trunk to scapula or clavicle

a. Trapezius- assists in suspending the pectoral girdle and elevates, retracts and rotates the scapula

b. Levator scapulae- pulls up the scapulac. Rhomboideus major/minor- adducts

scapula towards the midlined. Pectoralis minor- stabilizes the

scapula, for flexione. Subclavius- stabilizes (anchors and

depresses) the claviclef. Serratus anterior- (serrated

appearance); keeps scapula close to trunk and rotates it

2- Trunk to humerusa. Latissimus dorsi- widest back muscleb. Pectoralis major

**extends, adducts and rotates the humerus medially

Winging of the scapula- paralysis of serratus anterior / injury to long thoracic nerve- when the medial border of the scapula moves laterally and posteriorly away from the thoracic wall

AXILLA- The pyramidal space inferior to the

glenohumeral joint and is superior to the axillary fascia at the junction of the arm and thorax

MUSCLES OF PECTORAL REGION Scapula to humerus

1. Deltoid- triangular muscle that forms the rounded contour of the shoulder; middle area is multipennate; functions as the

principle abductor of the arm (flexion of shoulder joint)

2. Rotator Cuff muscles (scapulohumeral muscles- SITS)

a. Supraspinatusb. Infraspinatus- lateral rotatorc. Teres minord. Subscapularis- medial rotator

Initiate abduction for first 150 degrees; deltoid does the rest; grasps and pulls the humerus head against the glenoid cavity (reinforces anteriorly, superiorly and posteriorly)3. Teres major (+ Teres minor)- minor is

more superiorly located; both help in lateral rotation

SCAPULOHUMERAL DISSECTION*teres minor- above, major- below

- Quadrangular spaceo Teres minor, teres major, triceps

brachii (medial), humerus(lateral) Enervated by Axillary nerve Post humeral circumflex artery

runs through it- Triangular space

o Teres minor, teres major and triceps brachii

Circumflex scapular artery from subscapular artery runs through it

ARM: MUSCULAR COMPARTMENTS- Anterior- flexors (3)

o Enervated by musculocutaneous nerve

o Bloody supply from brachial arteryo Supinatoro Biceps brachii coracobrachialis

(passes only shoulder joint) and brachialis muscles

o Covered by superficial Antibrachial fascia

o Presence of bicipetal aponeurosis which forms a roof over cubital fossa and protects underlying structures

- Posterior- extensors (2)o Enervated by radial nerveo Blood supply c/o brachial arteryo Triceps brachii- long, lateral and

medial heads + Anconeus (muscle that assists the triceps in extending the elbow joint)

FOREARM: MUSCULAR COMPARTMENTS- Anterior- flexors (+pronators)

o Enervated by Median nerve and/or ulnar nerve (only 1 and a ½ exceptions are supplied by latter)

o 3 layers/groups 1 superficial group- common

flexor tendon; origin- medial epicondyle of humerus; made up of 4 muscles

Pronator teres Wrist flexors (3)- flexor

carpi radialis, Palmaris longus, and flexor carpi ulnaris

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2 intermediate group Flexor digitorum

superficialis muscle- flexes in fast action

3 deep group- flexors of digits and pronator (made up of 3 muscles)

Flexor digitorum profundus- flexes fingers in slow action

Flexor pollicis longus – extends the thumb, extrinsic muscle

Pronator quadrates- between the radius and ulna

** FYI- biceps brachii serves supinator function

- Cubital Fossa- triangular area in elbow which serves as an imaginary border; found by the brachialis muscle; filled with a variable amount of fat

o 3 boundaries Superiorly: imaginary line

connecting the medial and lateral epicondyle

Medially- mass of forearm flexor muscles (pronator teres) arising from a common flexor attachment on the medial epicondyle

Laterally- mass of extensor muscles (brachioradialis)

o Contents of fossa Terminal end of the brachial

artery- and divisions of radial and ulnar arteries

Deep accompanying veins of the arteries

Biceps brachii tendon Median nerve Radial nerve

- Posterior- Extensors (+supinator and forearm flexor)

o Enervated by the radial nerveo Divided into 3 functional groups

Extensor muscles of the wrist joint

Extensor muscles of the fingers

Thumb abductor and extensors

o Blood supply is from both radial and ulnar arteries

Flexor of the elbow joint (forearm)- brachioradialis which is slanted and found in the humerus to the radius

Exception to the rule that radial nerve

supplies only extensory muscles and that all flexors are found anteriorly (flexor compartment)

Extensors E. carpi radialis longus

and E. carpi radialis brevis- extends and abducts hand at wrist joint; for clenching

E. digitorum (communis)- extends 4 medial fingers

E. digiti minimi – extends 5th finger

E. carpi ulnaris- extends and adducts hand at wrist joint; for clenching

Supinator, Abductor and Extensor

Abd, pol. Longus E. pol. Brevis E. pol. Longus

** extends and abducts the thumb

E. indicis – extends 2nd finger (for independent extension)

- Anatomical Snuffboxo (triangular hollow) depression between

ext. pol. Longus and brevis tendonso Formed by scaphoid and trapezium

bones

FASCIA: WRIST AND HAND- Deep fascia continues from antebrachial fascia

I. Retinacula (At wrist region)a. Extensor retinaculumb. Flexor retinaculum- forms carpal

tunnel as it bridges carpal bones concavity; for passage of flexor digitorum profundus and superficialis and flexor pollicis longus** in the carpal tunnel runs the median nerve

c. Palmar carpal ligament- fund superficial to flexor retinaculum

II. Palmar Fasciaa. Thenar Fasciab. Hypothenar Fasciac. Palmar Aponeurosis

III. Dorsal fasciaIV. Fibrous Flexor Sheaths of Digits

(covering of Flexor Digitorum Tendons)

V. Vincula – attach superficial fascial and deep flexor tendons to middle and distal phalanges respectively; provide route for blood supply to tendons.

FASCIAL SPACES (4)- Carpal Tunnel- Thenar Compartment- Hypothenar Compartment- Central compartment

o Palmar Space Thenar Space Midpalmar Space

o Synovial Flexor Sheaths (for support)

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Ulnar Bursa – Contains tendons of Flexor Digitorum Superficialis and Profundus

Radial Bursa – Contains tendon of Flexor Pollicis Longus

Synovial Sheaths for second to Fourth Digits

INTRINSIC MUSCLES OF THE HAND- Nerve supply c/o ulnar nerve EXCEPT thenar

muscles and the 1st 2 lumbricals which are supplied by the median nerve

- Thenar compartment (act on thumb)o Abductor Pollicis breviso Flexor Pollicis breviso Opponens Pollicis

- Hypothenar compartment (act on little finger)o Abductor digiti minimio Flexor digiti minimio Opponens digiti minimi

- 12 short muscleso Lumbricals – in central compartment;

arise from flexor digitorum profundus; flexes metacarpophalangeal (MP) joint and extends dorsal and palmar interphalangeal (DIP and PIP) joints

1 and 2 = unipennate 3 and 4 = bipennate

o Muscles in Interossei- adductor compartment

3 palmar (adducts) and 4 dorsal (abducts)

1 Adductor pollicis (adducts the thumb)

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1 July 2009