Upper Limb
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Transcript of Upper Limb
Anatomy of the upper limb
• Introduction
• General considerations
• Brachial plexus
ANATOMYUPPER LIMB
BRACHIAL PLEXUS
The spinal nerves from C5 to C8, together with the T1 thoracic spinal nerve, join together to form
the brachial plexus.
The nerve elements combine,
divide and combine again to
mix together the various components that lead into the major nerves of the
shoulder, arm and hand.
A nerve plexus is an area where nerves branchand rejoin.
The brachial plexus is a group of nerves in the cervical spine from C5 to C8-T1.
This includes the lower half of the cervical nerve roots and the nerve root from the first thoracic vertebra.
Brachial Plexus
1 Ventral root of C5
2 Ventral root of C6
3 Ventral root of C7
4 Ventral root of C8
5 Ventral root of T1
6 Ulnar
7 Radial
8 Median
9 Musculocutaneous
10 Cords
a Medial
b Posterior
c Lateral
11 Posterior divisions
12 Anterior divisions
a Inferior
b Middle
c Superior
13 Inferior trunk
14 Middle trunk
15 Superior trunk
Erb’s paralysis
• C5 - C6
• Birth injury
• Arm hangs by the side+Rotate medially
• Forearm pronated + extended
• Flexed wrist + fingers
• deltoid – supraspinatus – infraspinatus –biceps - brachialis
Klumpke’s paralysis/kloomp’kz/
• C8 – T1
• Intrinsic muscles of the hand + long flexors of the hand ------ paralysis
• Claw hand = extension at MPJ + flexion at IPJ
• Cervical rib can cause paralysis similar to Klumpke’s paralysis with post-fixed T2 contribution
Winging of the scapula
• Injury to the long thoracic nerve
• Paralysis of serratus anterior muscle
At the surgical neck ---------- injury to the axillary nerve ---- loss of abduction
Humeral fracture
Arterial blood supplyof the upper limb
Axillary artery•Continuation of subclavian artery •Runs from lateral border of first rib to lower border of teres major •Pectoralis minor crosses anterior to it and divides it into three parts •First part
• Highest thoracic artery (also called supreme or superior) •Second part
• Lateral thoracic artery • Thoracoacromial artery
•Third part • Subscapular artery • Anterior circumflex humeral artery • Posterior circumflex humeral artery
•Collateral circulation around the scapula •Branches of first part of Subclavian artery anastomose with branches of the third part of axillary artery
The axillary artery begins at the lateral border of the first rib as a continuation of the subclavian artery.
It changes its name to brachial artery at lower (inferior) border of the teres major muscle.
For purposes of description, it is broken up into three parts by its relation to the pectoralisminor muscle.
The first part is between the lateral border of the first rib and the medial border of the pectoralis minor,
the second part is behind the pectoralis minor and the
third part is between the lateral border of the pectoralis minor and the inferior border of the teres major
Brachial arteryContinuation of the axillary artery Runs from lower border of teres major to neck of radius Ends by dividing into radial and ulnar arteries
Branches of the brachial arteryProfunda brachi which travels in the radial groove of humerusSuperior ulnar collateral artery o Inferior ulnar collateral artery Nutrient artery to humerusTerminal branches are radial and ulnar arteries
RelationsMedian nerve crosses anterior to it from lateral to medial side at the level of mid arm
1 superior thoracic a. (supreme thoracic a.) (highest thoracic a.)
2 thoracoacromial a. 3 lateral thoracic a.
4 subscapular a. 5 anterior humeral circumflex a. 6 posterior humeral circumflex a.
Ulnar artery Gives rise to common interosseous artery Continues as the superficial palmar arch in the hand
Radial arteryContinues as the deep palmar arch in the handMedian artery Vestigial in adult life
Arises from the anterior interosseous branch of common interosseous artery Provides nutrition to Median nerve Chief source of blood supply to the upper limb in foetal life Passes anterior to carpal tunnel
The diagram also shows that the brachial artery terminates just below the elbow joint as the radial and ulnar arteries, to be covered in the forearm
1 brachial 2 radial
3 radial recurrent 4 superficial radial 5 deep radial
6 ulnar7 anterior ulnar recurrent 7 posterior ulnar recurrent 8 common interosseous
9 posterior interosseous10 anterior interosseous
11 superficial branch 12 deep branch
The superficial arterial arch is formed mainly from the ulnar artery and is completed by the superficial branch of the radial. This completion is not always present or may be extremely small.The deep arterial arch is formed mainly by the deep branch of the radial artery andis finished by the deep branch of the ulnar artery.
Upper limb
Venous drainage
cephalic v.
Tributaries
lateral side of the dorsal venous arch of the hand; superficial veins of the forearm
Drains Into
axillary vein
Regions Drained
superficial parts of the lateral hand and lateral forearm
Notes
median cubital vein usually shunts some of the blood collected by the cephalic v. to the basilic v. (Latin/Greek, kephale = head)
The axillary vein lies along the medial side of the artery and is a continuation of the basilic vein.
It begins at the inferior border of the teres major m. and ends at the lateral border of the first rib, where it becomes the subclavian v.
It receives tributaries that parallel the branches of the axillary artery.
The cephalic v. joins the axillary v. just before it becomes the subclavian.
Penetrating wounds in the larger upper part are serious because air might enter into the venous system.
The veins that run with their corresponding arteries are frequently multiple (2 or 3 interconnected veins).This interconnected venous network is called the vena commitantes
Axilla, Pectoral andscapular regions
medially: serratus anterior and by the ribcage
anteriorly: by the pectoralis major, minor, and subclavius (see also anterior axillary fold)
posteriorly: by the subscapularis above, and teres major and latissimus dorsi below(see also posterior axillary fold)
laterally: by the intertubercular sulcus (coracobrachialis and the short head of the biceps brachii are in the axilla.)
superiorly: by the outer border of first rib, superior border of scapula, and posterior border of clavicle
floor/base: by the skin (visible surface of armpit
Anatomically, the boundaries of the axilla are
Deep muscles of the chest and front of the arm, with the boundaries of the axilla.
Artery axillary artery
Vein axillary vein
Nerve
axillary nerve, medial cord, posterior cord, lateral cord
Lymphaxillary lymph nodes
Lymphatics
Structure Location Afferents from Efferents to Regions drained Notes
axillary nodes axilla cubital nodes;lymphatic vessels from the upper limb, thoracic wall and subscapularregion
efferents vessels form the subclavian trunk, some drainage to inferior deep cervical nodes
upper limb, most of the mammary gland, some of the anterolateral chest wall, posterior thoracic wall and scapular region
axillary nodes number from 20 to 30 and are organized in five groups based on their position within the axilla: 1) pectoral nodes, along the lateral border of the pectoralis major m.; 2) lateral nodes, located along the distal axillary v.; 3) central nodes, centrally located along axillary v.; 4) subscapularnodes, located along the subscapular v. and its tributaries; 5) apical nodes, located at the apex of axilla
There are some 15 to 20 nodes usually arranged into to five groups. The groups consist of: A pectoral (anterior) L lateral P posterior C central Ap apical
Muscles of Axilla and the Pectoral region
Origin medial 1/2 of the clavicle, manubrium & body of sternum, costal cartilages of ribs 2-6, sometimes from the rectus sheath of the upper abdominal w
Pectoralis major
Insertion crest of the greater tubercle of the humerus
Action flexes and adducts the arm, medially rotates the arm
Nerve supply medial and lateral pectoral nerves (C5-T1)
the deep fascia on its anterior surface should not be fused to the fascia of the mammary gland - if it is, this is an important clinical sign indicating breast disease (Latin, pectus = breast bone)
Arterial blood supply pectoral branch of the thoracoacromial trunk
Pectoralis minororigin ribs 3-5 Insertion coracoid process of the scapulaAction draws the scapula forward, medialward, and downwardNerve supply medial pectoral nerve (C8, T1) arterial supply pectoral branch of the thoracoacromial trunk
Notes; branches of medial pectoral nerve usually pierce pectoralis minor to reach the pectoralis major muscle .
serratus anteriorOrigin ribs 1-8 or 9Insertion medial border of the scapula on its costal (deep) surfaceAction it draws the scapula forward; the inferior fibers rotate the scapula superiorly
Nerve supply long thoracic nerve (from ventral rami C5-C7) Arterial supply
lateral thoracic a.
a lesion of long thoracic nerve will cause winging of the scapula (i.e., the medial border of the scapula falls away from the posterior chest wall and looks like an angel's wing) (Latin, serratus = to saw)
Topographical Anatomy of the Thorax
Structure/Space Description/Boundaries Significance
midaxillary line an imaginary vertical line passing through the middle of the axilla
used as a surface landmark for descriptive purposes
midclavicular line an imaginary vertical line passing through the midshaft of the clavicle
used as a surface landmark for descriptive purposes
deltopectoral triangle
a triangle in the upper chest region that is bounded medially by the clavicle,superiorly by the deltoid m.,
and inferiorly by the pectoralis major m.
the deltopectoral triangle
is pierced by the cephalic vein on its course from the upper limb to join the axillary vein in the axilla
nipple located superficial to the 4th intercostal space in the male and prepuberal female; areola is dark ring surrounding nipple
location of the left nipple may be used to help locate the apex of heart, which is approximately 8 cm from the midline in the left 5th intercostal space; a surface landmark used to place the stethoscope for auscultation of the bicuspid valve
suprasternal notch the notch located at the superior border of the manubrium of the sternum, between the sternal ends of the clavicles
also known as: jugular notch
parasternal nodes lateral border of sternum, along the course of the internal thoracic vessels
anterior phrenic nodes, lymphatic vessels from the anterior thoracic wall
larger lymphatic vessels in the root of the neck
medial side of the mammary gland; medial part of the anterior chest wall and muscles
parasternal nodes constitute an important drainage pattern in cases of cancer of the mammary gland; one or two parasternal nodes may be found in the anterior end of intercostal spaces 1-6; also known as: sternal nodes
pectoral nodes along the lateral border of the pectoralis major m. along the course of the lateral thoracic vessels
lymphatic vessels from the mammary gland and anterolateral thoracic wall
central axillary nodes anterolateral thoracic wall and muscles; most of the mammary gland
an important group of nodes to examine during a breast physical exam; also known as: anterior axillary nodes
SCAPULAR REGION
Muscles of the Scapular Region
Muscle Origin Insertion Action Innervation Artery Notes
deltoid lateral one-third of the clavicle, acromion, the lower lip of the crest of the spine of the scapula
deltoid tuberosity of the humerus
abducts arm; anterior fibers flex & medially rotate the arm; posterior fibers extend & laterally rotate the arm
axillary nerve (C5,6) from the posterior cord of the brachial plexus
posterior circumflex humeral a.
the deltoid muscle is the principle abductor of the arm but due to poor mechanical advantage it cannot initiate this action; it is assisted by the supraspinatus m.
teres major dorsal surface of the inferior angle of the scapula
crest of the lesser tubercle of the humerus
adducts the arm, medially rotates the arm, assists in arm extension
lower subscapular nerve (C5,6) from the posterior cord of the brachial plexus
circumflex scapular a.
teres major inserts beside the tendon of latissimus dorsi, and assists latissimus in its actions
triceps brachii long head: infraglenoid tubercle of the scapula; lateral head: posterolateral humerus & lateral intermuscular septum; medial head: posteromedial surface of the inferior 1/2 of the humerus
olecranon process of the ulna
extends the forearm; the long head extends and adducts arm
radial nerve deep brachial (profunda brachii) a.
long head of the triceps separates the triangular and quadrangular spaces (teresmajor, teres minor and the humerusare the other boundaries); all three heads of origin insert by a common tendon
rotator cuff
supraspinatus supraspinatous fossa
greater tubercle of the humerus (highest facet)
abducts the arm (initiates abduction)
suprascapular nerve (C5,6) from the superior trunk of the brachial plexus
suprascapular a.
supraspinatus initiates abduction of the arm, then the deltoid muscle completes the action; a member of the rotator cuff group
infraspinatus infraspinatous fossa
greater tubercle of the humerus (middle facet)
laterally rotates the arm
suprascapular nerve
suprascapular a.
infraspinatus, supraspinatus, teres minor and subscapularis are the rotator cuff muscles
teres minor upper 2/3 of the lateral border of the scapula
greater tubercle of the humerus (lowest facet)
laterally rotates the arm
axillary nerve (C5,6) from the posterior cord of the brachial plexus
circumflex scapular a.
fixes the head of the humerus in the glenoid fossa during abduction & flexion of the arm; a member of the rotator cuff group
subscapularis medial two-thirds of the costal surface of the scapula (subscapular fossa)
lesser tubercle of the humerus
medially rotates the arm; assists extention of the arm
upper and lower subscapular nerves (C5,6)
subscapular a.
subscapularis, supraspinatus, infraspinatus, and teresminor are the rotator cuff muscles
Nerves of the Scapular Region
Nerve Source Branches Motor Sensory Notes
axillary n. posterior cord of the brachial plexus
superior lateral brachial cutaneous nerve
deltoid, teres minor
skin of the upper lateral arm
axillary n. is endangered by surgical neck fractures
lower subscapular n.
posterior cord of the brachial plexus (C5, C6)
unnamed muscular brs.
subscapularis m., teres major m.
no cutaneous branches
subscapularis and teres major are synergists (medial rotation of the humerus)
middle subscapular n.
posterior cord of the brachial plexus (C7, C8)
unnamed muscular brs.
latissimus dorsi m.
no cutaneous branches
also called the thoracodorsal n.
suprascapular n. superior trunk of the brachial plexus (C5-C6)
no named branches
supraspinatus m., infraspinatus m.
no cutaneous branches
suprascapular n. passes through the scapular notch inferior to the superior transverse scapular ligament
thoracodorsal n. posterior cord of the brachial plexus (C7, C8)
unnamed muscular brs.
latissimus dorsi m.
no cutaneous branches
also called the middle subscapular n.
upper subscapular n.
posterior cord of the brachial plexus (C5, C6)
unnamed muscular brs.
subscapularis m. no cutaneous branches
subscapularis is a strong medial rotator of the humerus
Arteries of the Scapular Region
Artery Source Branches Supply to Notes
anterior circumflex humeral axillary a., 3rd part unnamed muscular branches deltoid m.; arm muscles near the surgical neck of the humerus
anterior circumflex humeral a. anastomoses with the posterior circumflex humeral a.
posterior circumflex humeral axillary a., 3rd part unnamed muscular branches deltoid; arm muscles near the surgical neck of the humerus
posterior circumflex humeral a. anastomoses with the anterior circumflex humeral a.; it passes through the quadrangular space with the axillary nerve
axillary subclavian a. (axillary a. is the continuation of the subclavian lateral to the 1st rib)
1st part: superior thoracic a.; 2nd part: thoracoacromial a., lateral thoracic a.; 3rd part: anterior humeral circumflex a., posterior humeral circumflex a., subscapular a.
pectoral region, shoulder region and upper limb
pectoralis minor m. crosses anterior to the axillary artery and is used to delineate the 3 parts mentioned at left
circumflex scapular subscapular a. unnamed muscular branches teres major m., teres minor m., infraspinatus m.
circumflex scapular a. anastomoses with the suprascapular a. and the dorsal scapular a. to form the scapular anastomosis
dorsal scapular subclavian a., 3rd part unnamed muscular branches levator scapulae m., rhomboideus major m., rhomboideus minor m.
dorsal scapular a. anastomoses with the suprascapular a. and the subscapular a. to form the scapular anastomosis; dorsal scapular a is a branch of the transverse cervical a. in ~30% of cases
subscapular axillary a., 3rd part circumflex scapular a., thoracodorsal a.
subscapularis m., teres major m., teres minor m., infraspinatus m.
the circumflex scapular branch of the subscapular a.anastomoses with the suprascapular a. and the dorsal scapular a. in the scapular anastomosis
suprascapular thyrocervical trunk muscular supraspinatus & infraspinatus, shoulder joint
anastomoses with the circumflex scapular a. and the dorsal scapular a. to form the scapular anastomosis
thoracodorsal subscapular a. unnamed muscular branches latissimus dorsi m. thoracodorsal a. accompanies the thoracodorsal n.
Topographic Anatomy of the Scapular Region
Structure/Space Description/Boundaries Significance
quadrangular space the space bounded by the teres minor m. superiorly, the teres major m. inferiorly, the long head of the triceps brachii m. medially and the humerus laterally
the axillary n. and the posterior circumflex humeral a. pass through this space
triangular interval the interval between the teres major m. superiorly, long head of the triceps brachii m. medially and humerus laterally
the radial n. passes through this interval to get from the axilla to the posterior surface of the humerus
triangular space the space bounded by the teres minor m. superiorly, the teres major m. inferiorly and the long head of the triceps brachii m. laterally
the circumflex scapular vessels are located in this space as they pass from the axilla to the dorsum of the scapula
The scapular and circumflex arteries. (Quadrangular space is visible but not labeled. Posterior humeral circumflex artery is visible entering quadrangular space at center right.)
Suprascapular and axillary nerves of right side, seen from behind. Quadrangular space is the lateral space, labeled in green at center right. Axillary nerve is visible entering it.
Pectoral region
The human breast
(Mammary gland )
consists of 10–20 simple glands.
The presence of more than two nipples is known as polythelia
and the presence of more than two complex mammary glands as polymastia.
I. Introduction/General Information
A. Embryologically: belong to integument
B. Functionally: part of reproductive system
1. Respond to sexual stimulation
2. Feed babies
C. Modified apocrine sweat glands
- apex of cell becomes part of secretion and breaks off
D. Present in males and females
II. Anatomy
A. Position and Attachment
1. Lateral aspect of pectoral region
2. Located between ribs 3 and 6/7
3. Extend form sternum to axilla
4. Surrounded by superficial fascia
5. Rest on deep fascia
6. Fixed to skin & underlying fascia by fibrous C.T. bandsa. Cooper’s (Suspensory) Ligamentsb. Ligaments may retract when breast tumors are present
Breast Anatomy
Left breast is usually slightly larger
Base is circular, either flattened or concave
Separated from pectoralis major muscle by fascia, retromammary space
B. Structure
1. Outer surface convex, skin covered
2. Nipple:
a. At fourth intercostal space
b. Small conical/cylindrical prominence below center
Nipple location
4th intercostal space
c. Surrounded by areola: pigmented ring of skin
d. Thin skinned region lacking hair, sweat glands
e. Contains areolar glands
3. Areola: contains
dark pigment that intensifies with pregnancy
a. Circular and radial smooth muscle fibers
b. Cause nipple erection
Lobes and Lobules
5. Excretory (lactiferous) ducts converge toward areola
a. Form ampullae (collection sites of lactiferous sinuses)
b. Ducts become contracted at base of nipple
6. Secretory epitheliuma. Changes with hormonal signals
b. Onset of menstruation
c. Pregnancy (glands begin to enlarge at 2nd month)d. After birth, 1st secretion is colostrom (contain antibodies
7. “Tail of Spence” = axillary tail a. prolongation of upper, outer quadrant in axillary direction
b. Passes under axillary fascia
c. May be mistaken for axillary lymph nodes
8. Fatty Tissue: surrounds surface, fills spaces between lobes
a. Determines form & size of breast
b. No fatty deposit under nipple & areola
“Tail of Spence”
Axillary Tail
Breast: Fatty Tissue
Vessels & nerves
1. Arteries: derived from thoracic branches of three pairs of arteries
a. Axillary arteries
continuous with subclavian a.
gives rise to external mammary ( = lateral thoracic) artery
b. Internal mammary (thoracic) arteries
1) first descending branch of subclavian artery
2) supply intercostal spaces & breast
3) used for coronary bypass surgery
c. Intercostal arteries:
1) numerous branches from internal & external mammary arteries
2) supply intercostal spaces & breast
Veins: a. form a ring around the base of the nipple (“circulus
venosus”)
b. Large veins pass from circulus venosus to circumference
Of mammary gland, then toc. External mammary v to axillary v or d. Internal mammary v to subclavian v
Subclavian a.
Axillary a.
External mammary (thoracic) a.
Internal mammary (thoracic) a.
Arterial Supply to the Breast
Veins draining the Breast
Subclavian vein
External mammary vein
Innervation: derived from:a. anterior & lateral cutaneous nerves of thorax b. spinal segments T3 – T6
Lymphatics: clinically significant!a. Glandular lymphatics drain into
anterior axillary (pectoral) nodes
central axillary nodes
apical nodes
deep cervical nodes subclavicular (subclavian) nodesb. Medial quadrants drain into parasternal nodes
c. Superficial regions of skin, areola, nipples: -form large channels & drain into pectoral nodes
d. NOTE: axillary nodes also drain lymph from arm
Subclavian nodes
Axillary nodes
Lateral pectoral
nodes
Parasternal nodes
Lymph Nodes of the Breast
Lymph Nodes and Lymph Drainage
Axillary Nodes
Routes of Metastasis
• From medial lymphatics to parasternal nodes
– Then to mediastinal nodes
• Across the sternum in lymphatics to
opposite side via cross-mammary pathways
– Then to contralateral breast
• From subdiaphragmatic lymphatics to nodes in abdomen
– Then to liver, ovaries, peritoneum
Subdiaphragmatic Lymph Channels
Channels to Contralateral Breast
Axillary Lymph Channels
Major Routes of Metastasis
The veins describe anastomotic circle around the base of the papilla, called by Haller the circulus venosus.From this, large branches transmit the blood to the circumference of the gland, and end in the axillary and internal mammary veins.
The arteries supplying the mammæ are derived from the thoracic branches of the axillary,
the intercostals,and the internal mammary.
The arteries supplying the mammæ are derived from the thoracic branches of the axillary,
the intercostals,and the internal mammary.
Muscles of the upper limb
ORIGINCoracoid process of scapula with biceps brachii
INSERTIONUpper half medial border of humerus
ACTIONFlexes and weakly adducts arm
NERVEMusculocutaneous nerve (C5, 6, 7) (from lateral cord)
CORACOBRACHIALIS
Latin musculus brachialis
Gray's subject #124 444
Origin anterior surface of the humerus, particularly the distal half of this bone
Insertion coronoid process and the tuberosity of the ulna
Artery radial recurrent artery
Nerve musculocutaneous nerve
Actions flexion at elbow joint
The biceps is tri-articulate, meaning that it works across three joints. The most important of these functions are to supinate the forearm and flex the elbow.These joints and the associated actions are listed as follows in order of importance
Proximal radioulnar joint
Humeroulnar joint
Glenohumeral joint
Latin musculus biceps brachii
Gray's subject #124 443
Origin short head: coracoid process of the scapula. long head: supraglenoid tubercle
Insertion radial tuberosity and bicipittal aponeurosis into deep fascia on medial part of forearm
Artery brachial artery
Nerve Musculocutaneous nerve (C5–C7)
Actions flexes elbow and supinates forearm
Antagonist Triceps brachii muscle
Muscle Origin Insertion Artery Nerve Action Antagonist
coracobrachialis coracoid process of scapula
medial humerus brachial artery musculocutaneous nerve
adducts humerus
biceps brachii short head: coracoid process of the scapula. long head: supraglenoid tubercle
radial tuberosity brachial artery Musculocutaneous nerve (Lateral cord: C5, C6, C7)
flexes elbow and supinatesforearm
Triceps brachii muscle
brachialis anterior surface of the humerus, particularly the distal half of this bone
coronoid process and the tuberosity of the ulna
radial recurrent artery
musculocutaneous nerve
flexion at elbow joint
Anterior compartment
POSTERIOR COMPARTMENT
• TRICEPS MUSCLE
Schematic drawing with measurements indicating the relationship of the radial nerve to osseous landmarks.
Note the course of the radial nerve along the posterior humerus and its relationship to the distal deltoid tuberosity and lateral epicondyle
MUSCLES THAT ACT ON ANTERIOR FOREARM:•BICEPS BRACHII•BRACHIALIS•BRACHIORADIALIS•PRONATOR TERESMUSCLES THAT ACT ON POSTERIOR FOREARM:•TRICEPS BRACHII - LONG HEAD•TRICEPS BRACHII - MEDIAL HEAD•TRICEPS BRACHII - LATERAL HEAD•ANCONEUS
Muscle Origin Insertion Artery Nerve ActionAntagonist
triceps brachii
long head:scapulalateral head:posterior humerusmedial head:posterior humerus
olecranonprocess of ulna
Profundabrachii
radial nerve
extendsforearm, caput longum adductsshoulder
Biceps brachii muscle
anconeus
Lateral epicondyle of the humerus
lateral surface of the olecranonprocess and the superior part of the posterior ulna
Profundabrachii, recurrent interosseousartery
radial nerve(C7, C8, and T1)
partly blended in with the triceps, which it assists in extension of the forearm. Stabilises the elbow and abducts the ulna during pronation.
Posterior compartment
Cubital FossaThe cubital fossa is the region of the upper limb in front of the elbow joint.
It is a triangular area with the following boundaries:
laterally, brachioradialis muscle medially, pronator teres muscle superiorly, an imaginary line from the
medial and lateral epicondyles.
venous layer1 cephalic vein 2 basilic vein 3 median cubital vein
artery-nerve layer1 brachial artery 2 median nerve
bony floor1 humerus2 radius 3 ulna
aponeurotic layer1 bicipital aponeurosis 2 biceps tendon
muscular floor1 supinator2 brachialis3 biceps tendon
ForearmAnterior compartment
flexor carpi radialisorigincommon flexor tendon from the medial epicondyle of the humerusinsertionbase of the second and third metacarpalsactionflexes the wrist, abducts the handNerve supplymedian nerve
flexor carpi ulnaris
Origincommon flexor tendon & (ulnar head) from medial border of olecranon & upper 2/3 of the posterior border of the ulnainsertionpisiform, hook of hamate, and base of 5thmetacarpalactionFlex the wrist, adducts handNerve supplyulnar nerve
flexor digitorum profundusoriginposterior border of the ulna, proximal two-thirds of medial border of ulna, interosseousmembrane insertionbase of the distal phalanx of digits 2-5actionflexes the metacarpophalangeal, proximal interphalangeal and distal interphalangeal jointsNerve supplymedian nerve via anterior interosseous branch (radial one-half); ulnar nerve (ulnar one-half)
flexor digitorum superficialisoriginhumeroulnar head: common flexor tendon; radial head: middle 1/3 of radius insertionshafts of the middle phalanges of digits 2-5 actionflexes the metacarpophalangealand proximal interphalangeal jointsNerve supplymedian nerve
flexor pollicis longus
originanterior surface of radius and interosseousmembraneinsertionbase of the distal phalanx of the thumbactionflexes the metacarpophalangeal and interphalangeal joints of the thumb Nerve supplymedian nerve via anterior interosseousbranch
pronator quadratus
originmedial side of the anterior surface of the distal one-fourth of the ulna insertionanterior surface of the distal one-fourth of the radius actionpronates the forearm Nerve supplymedian nerve via anterior interosseousbranch
palmaris longus
originmedial epicondyle of humerusinsertiondistal half of flexor retinaculum and palmaris aponeurosisactionflexes hand (at wrist) and tightens palmar aponeurosisNerve supplymedian n. (C7 and C8) ulnar a.
pronator teresorigincommon flexor tendon and (deep or ulnar head) from medial side of coronoid process of the ulna inserionmidpoint of the lateral side of the shaft of the radius Actio pronates the forearmNerve supplymedian nerve
supinatororiginlateral epicondyle of the humerus, supinator crest & fossa of the ulna, radial collateral ligament, annular ligamentinsertionlateral side of proximal one-third of the radiusactionsupinates the forearm Nerve supplydeep radial nerve
Muscle Origin Insertion Artery Nerve Action Antagonist
pronator teres
humeral head: medial epicondyle of humerus(common flexor tendon)ulnar head: coronoid process of the ulna
radius ulnar artery and radial artery
median nerve
pronation of forearm, flexeselbow
Supinator muscle
palmaris longus
medial epicondyle of humerus(common flexor tendon)
palmar aponeurosis
ulnar artery
median nerve
wrist flexor Extensor carpiradialisbrevis, Extensor carpiradialislongus, Extensor carpiulnaris
flexor carpi radialis
medial epicondyle of humerus(common flexor tendon)
Bases of second and third metacarpal bones
ulnar artery Median nerve
Flexion and abduction at wrist
Extensor carpi radialis brevis muscle, Extensor carpi radialis longus muscle
flexor carpi ulnaris
medial epicondyle of the humerus(common flexor tendon)
pisiform ulnar artery muscular branches of ulnar nerve
flexion of wrist
Extensor carpi ulnaris muscle
flexor digitorum superficialis
medial epicondyle of the humerus(common flexor tendon), as well as parts of the radiusand ulna.
phalanges ulnar artery median nerve flexor of fingers(primarily at proximal interphalangeal joints)
Extensor digitorummuscle
Muscle Origin Insertion Artery Nerve Action Antagonist
pronator quadratus
medial, anterior surface of the ulna
lateral, anterior surface of the radius
anterior interosseous artery
median nerve(anterior interosseous nerve)
pronates the forearm Supinator muscle
flexor digitorum profundus
ulna distal phalanges anterior interosseous artery
median(anterior interosseous), muscular branches of ulnar
flex hand, interphalangeal joints
Extensor digitorum muscle
flexor pollicis longus
The middle 2/4 of the volar [disambiguation
needed] surface of the radius and the adjacent interosseus membrane. (Also occasionally a small origin slightly on the medial epicondyle of the ulna.)
The base of the distal phalanx of the thumb
Anterior interosseous artery
Anterior interosseous nerve(branch of median nerve) (C8, T1)
Flexion of the thumb Extensorpollicislongusmuscle, Extensorpollicisbrevismuscle
Deep
The muscles are largely involved with flexion and pronation.
The superficial muscles have their origin on the common flexor tendon.
The Ulna nerve and artery are also contained within this compartment@@@@@@@@@@@@@@@@
Forearm posterior compartment
abductor pollicis longusorigin middle one-third of the posterior surface of the radius, interosseousmembrane, mid-portion of posterolateral ulna
Insertion radial side of the base of the first metacarpal
Action abducts the thumb at carpometacarpal joint
Nerve supply radial nerve, deep branch
Brachioradialis
origin upper two-thirds of the lateral supracondylar ridge of the humerus
Insertion lateral side of the base of the styloidprocess of the radius
Action flexes the elbow, assists in pronation & supination
Nerve supply radial nerve
The Brachioradialis, flexor of the forearm, is
unusual in that it is located in the
posterior compartment, but it is actually in the anterior portion of the forearm.
extensor carpi radialis longus
Origin lower one-third of the lateral supracondylar ridge of the humerus
Insertion dorsum of the second metacarpal bone (base)
Action extends the wrist; abducts the hand
Nerve supply radial nerve
extensor carpi radialis brevisorigincommon extensor tendon (lateral epicondyle of humerus)insertiondorsum of the third metacarpal bone (base)
Action extends the wrist; abducts the hand
Nerve supply deep radial nerve
extensor carpi ulnarisorigin common extensor tendon & the middle one-half of the posterior border of the ulna insertionmedial side of the base of the 5th metacarpal actionextends the wrist; adducts the hand Nerve supply deep radial nerve
extensor digiti minimiorigincommon extensor tendon (lateral epicondyle of the humerus) insertionjoins the extensor digitorum tendon to the 5th digit and inserts into the extensor expansion actionextends the metacarpophalangeal, proximal interphalangeal and distal interphalangealjoints of the 5th digit
Nerve supply deep radial nerve
extensor digitorumorigincommon extensor tendon (lateral epicondyle of the humerus) insertionextensor expansion of digits 2-5actionextends the metacarpophalangeal, proximal interphalangeal and distal interphalangeal joints of the 2nd-5th digits; extends wrist deepNerve supply radial nerve
extensor indicisorigininterosseous membrane and the posterolateral surface of the distal ulnaInsertionits tendon joins the tendon of the extensor digitorum to the second digit; both tendons insert into the extensor expansionactionextends the index finger at the metacarpophalangeal, proximal interphalangeal and distal interphalangealjointsNerve supply deep radial nerve
extensor pollicis brevis
origininterosseous membrane and the posterior surface of the distal radius insertionbase of the proximal phalanx of the thumb actionextends the thumb at the metacarpophalangeal joint Nerve supplydeep radial
extensor pollicis longusOrigininterosseous membrane and middle
part of the posterolateral surface of the ulna insertionbase of the distal phalanx of the thumb actionextends the thumb at the interphalangeal joint Nerve supplydeep radial nerve
Nerves of the upper limbs
Radial nerve
Median nerve
Ulnar nerve
RADIAL NERVE
The radial nerve originates as a terminal branch of the posterior cord of the brachial plexus.
It goes through the arm, first in the posterior compartment of the arm,
and later in the anterior compartment of the arm,
and continues in the posterior compartment of the forearm.
In armFrom the brachial plexus, it travels posteriorly through what is often called the triangular interval (US) or the triangular space of the axilla (UK).
The radial nerve enters the arm behind the axillary artery/brachial artery, and it then travels posteriorly on the medial side of the arm.
After giving off branches to the long and medial heads of the triceps brachii, it enters a groove on the humerus, the radial sulcus.
Along with the deep brachial artery, the radial nerve winds around in the groove (between the medial and lateral heads of the triceps) towards the forearm, running laterally on the posterior aspect of the humerus.
While in the groove, it gives off a branch to the lateral head of the triceps brachii.The radial nerve emerges from the groove on the lateral aspect of the humerus.At this point, it pierces the lateral intermuscular septum and enters the anterior compartment of the arm.
It continues its journey inferiorly between the brachialis and brachioradialis muscles.When the radial nerve reaches the distal part of the humerus, it passes anterior to the lateral epicondyle and continues in the forearm
Branches/InnervationsThe following are branches/innervations of the radial nerve (including the superficial branch of the radial nerve and the deep branch of the radial nerve/posterior interosseous nerve).
Cutaneous
Cutaneous innervation is provided by the following nerves:
Posterior cutaneous nerve of arm (originates in axilla)
Inferior lateral cutaneous nerve of arm (originates in arm)
Posterior cutaneous nerve of forearm (originates in arm)
The superficial branch of the radial nerve provides sensory innervation to much of the back of the hand, including the web of skin between the thumb and index finger
Transverse section across distal ends of radius and ulna.
In forearmIn the forearm, it branches into a superficial branch (primarily sensory) and a deep branch (primarily motor).
The superficial branch of the radial nerve descends in the forearm under the brachioradialis.It eventually pierces the deep fascia near the back of the wrist.
The deep branch of the radial nerve pierces the supinator muscle, after which it is known as the posterior interosseous nerve.
MotorMuscular branches of the radial nerve:Triceps brachiiAnconeusBrachioradialisExtensor carpi radialis longus
Deep branch of the radial nerve:Extensor carpi radialis brevisSupinator
Posterior interosseous nerve (a continuation of the deep branch after the supinator):Extensor digitorumExtensor digiti minimiExtensor carpi ulnarisAbductor pollicis longusExtensor pollicis brevisExtensor pollicis longusExtensor indicis
The Median nerveis derived from the lateral and medial cords of the Brachial plexus.
Disk herniations in the Cervical spine (at the level of C5-C8 and T1) can cause numbness and/or decreased grip-strength in the hand
the median nerve courses with brachial artery on medial side of arm between biceps brachii and brachialis.
At first lateral to the artery, it then crosses anteriorly to run medial to the artery in the distal arm and into the cubitalfossa.
The median nerves arises from the cubital fossa and passes between the two heads of pronator teres.
It then travels between flexor digitorum superficialis and flexor digitorum profundus
before emerging between flexor digitorum superficialisand flexor carpi radialis
The unbranched portion of the median nerve innervates muscles of superficial and intermediate groups of the anterior
compartment exceptflexor carpi ulnaris
The median nerve does give off two branches as it courses through the forearm:
The anterior interosseous branch courses with the anterior interosseous artery and innervates all the muscles of the anterior compartment of the forearm except the flexor carpi ulnaris and the medial (ulnar) half of flexor digitorum profundus. Its ends with its innervation of pronator quadratus.
The palmar cutaneous branch of the median nerve arises at the distal part of the forearm. It supplies sensory innervation to the lateral aspect of the skin of the palm (but not the digits).
DistributionArmThe median nerve has no voluntary motor or cutaneous function in the (upper) arm. It gives vascular branches to the wall of the brachial artery. These vascular branches carry sympathetic fibers.ForearmIt innervates all of the flexors in the forearm except flexor carpi ulnaris and that part of flexor digitorum profundus that supplies the medial two digits. The latter two muscles are supplied by the ulnar nerve (specifically the Muscular branches of ulnar nerve).The main portion of the median nerve supplies the following muscles:Superficial group:Pronator teres Flexor carpi radialis Palmaris longusIntermediate group:Flexor digitorum superficialis muscleThe anterior interosseus branch of the median nerve supplies the following muscles:Deep group:Flexor digitorum profundus (only the lateral half) Flexor pollicis longusPronator quadratus
MEDIAN NERVEBranches in the handThe median nerve enters the hand through the carpal tunnel, deep to the flexor retinaculum along with the tendons of flexor digitorum superficialis, flexor digitorum profundus, and flexor pollicis longus.From there it sends off several branches:1. Recurrent branch to muscles of the thenar compartment (the recurrent branch is also called "the million dollar nerve")[1]
2. Digital cutaneous branches to common palmar digital branch and proper palmar digital branch of the median nerve which supply the:
a) lateral (radial) three and a half digits on the palmar side b) index, middle and ring finger on dorsum of the hand
The median nerve supplies motor innervation to the first and second lumbricalmuscles.
HandIn the hand, the median nerve supplies motor innervation to the 1st and 2nd lumbricalmuscles.
It also supplies the muscles of the thenareminence by a recurrent thenar branch.
The rest of the intrinsic muscles of the hand are supplied by the ulnar nerve.
The muscles of the hand supplied by the median nerve can be
remembered using the mnemonic, "LOAF" for
Lumbricals 1 & 2,
Opponens pollicis,
Abductor pollicis brevis
and Flexor pollicis brevis.
The median nerve innervates the skin of the palmar side of the thumb, the index and middle finger,
half the ring finger, and the nail bed of these fingers
The Opponens pollicis muscle is innervated exclusively by the Median nerve
. The inability to firmly hold an object between the index finger and thumb is a classic sign of Median nerve pathology.
The lateral part of the palm is supplied by the palmarcutaneous branch of the median nerve, which leaves the nerve proximal to the wrist creases.
This palmar cutaneous branch travels in a separate fascial groove adjacent to the flexor carpi radialis and then superficial to the flexor retinaculum.
It is therefore spared in carpal tunnel syndrome.
ULNAR NERVE
ArmThe ulnar nerve comes from the medial cord of the brachial plexus, and descends on the posteromedial aspect of the humerus. It goes behind the medial epicondyle, through the cubital tunnel, at the elbow
ForearmIt enters the anterior (flexor) compartment of the forearm through the two heads of flexor carpi ulnaris and runs alongside the ulna. There it supplies one and a half muscles (flexor carpi ulnaris & medial half of flexor digitorum profundus).It soon joins with the ulnar artery, and the two travel inferiorly together, deep to the flexor carpi ulnaris muscle.
In the forearm it gives off the following branches:[2]
Muscular branches of ulnar nervePalmar branch of ulnar nerveDorsal branch of ulnar nerve
Hand
After it travels down the ulna, the ulnar nerve enters the palm of
the hand.
The ulnar nerve and artery pass superficial to the
flexor retinaculum, via the ulnar canal
The course of the ulnar nerve through the wrist contrasts with
that of the median nerve, which travels deep to the flexor retinaculum of the hand and therefore through the carpal tunnel
In the handUlnar nerve gives
Superficial branch of ulnar nerveDeep branch of ulnar nerve
HAND ANATOMYAND
THE WRIST
Carpal bones1. scaphoid2. lunate3. triquetrum4. pisiform5. trapezium 6. trapezoid 7. capitate8. hamate hook of hamate
Metacarpal bones9. I 10. II 11. III 12. IV 13. V
Phalanges proximal 14 middle 15 distal 16
•flexor retinaculum (FR) •1 scaphoid•2 trapezium •3 pisiform•4 hamate
median nerve tendons of flexor digitorum superficialistendons of flexor digitorum profundustendon of flexor pollicis longustendon of flexor carpi radialis
Muscles of the Hand From Superficial to Deep
The intrinsic muscles of the hand can be arranged into three groups
according to either to a region or to depth.
Regional groups of muscles are the thenar and hypothenar group.
The thenar muscles are three in number and act on the thumb.
The hypothenar group are three in number and act on the little finger.
The ramainder muscles can be arranged from superficial to deep as
shown in the diagrams below.
Once the palmar aponeurosis is removed, the first layer is made up of
the tendons of the flexor digitorum superficialis. This and the other
layers are shown below.
Flexor digitorumsuperficialis
Palmar aponeurosis Lumbricals
Palmar interossei
Dorsal interossei
The superficial arterial arch is formed mainly from the ulnar artery and is completed by the superficial branch of the radial. This completion is not always present or may be extremely small.The deep arterial arch is formed mainly by the deep branch of the radial artery andis finished by the deep branch of the ulnar artery.
The dorsal venous plexus of the hand and the ensuing cephalic (1) and basilic (2) veins drain the superficial aspects of the hand.
The cephalic vein ends up in the axillary vein just before it becomes the subclavian and the basilic vein joins the brachial vein to become the axillary vein.
posterior antebrachial cutaneous skin of dorsum of wrist
radial nerveskin of dorsum of thumb and
2 1/2 digits as far as the distal interphalangeal joint
ulnar nerveulnar 1 1/2 digits and
adjacent part of dorsum of hand
Dorsum of Hand
ulnar nerve
sensory to skin of ulnar 1 1/2 digits
motor to muscles of hypothenar eminence
motor to ulnar two lumbricalsmotor to 7 interossei
motor to adductor pollicismuscle
median nerve
sensory to skin of palmaraspect of thumb and 2 1/2
digits including the skin on the dorsal
aspect of the distal phalanges
motor to muscles of thenareminence
motor to radial two lumbricalmuscles
palm of hand
abductor digiti minimi (hypothenar muscle)
pisiformproximal phalanx of little
fingerulnar abducts little finger
flexor digiti minimi (hypothenar muscle)
flexor retinaculumhook of hamate
proximal phalanx of little finger
ulnar flexes little finger
opponens digiti minimi (hypothenar muscle)
flexor retinaculumhook of hamate
5th metacarpal ulnaropposes little finger to
other digits
palmar interosseus Imedial side of 2nd
metacarpalmedial base of index finger ulnar
adducts index finger towards middle finger
interosseous IIlateral side of 4th
metacarpallateral base of ring finger ulnar
adducts ring finger towards middle finger
interosseous IIIlateral side of 5th
metacarpalmedial base of little finger ulnar
adducts little finger towards middle finger
dorsal interosseous Iadjacent sides of
metacarpal boneslateral aspect of extensor expansion of ring finger
ulnarabducts ring finger away
from middle finger
dorsal interosseous IIadjacent sides of
metacarpal bonesmedial aspect of extensor expansion of middle finger
ulnarabducts the middle finger
away from its long axis
dorsal interosseous IIIadjacent sides of
metacarpal boneslateral aspect of extensor
expansion of middle fingerulnar
abducts the middle finger away from its long axis
dorsal interosseous IVadjacent sides of
metacarpal boneslateral aspect of extensor expansion of index finger
ulnarabducts the index finger away from the middle
finger
lumbricals I & IItendons of flexor
digitorum superficialislateral aspect of extensor
expansionmedian
flex the metacarpophalangeal joint extend the interphalangeal
joints
lumbricals III & IVtendons of flexor
digitorum superficialislateral aspect of extensor
expansionulnar
flex the metacarpophalangeal joint extend the interphalangeal
joints
deep nerves of palm of hand
superficial nervesof palm of hand
dorsum of the hand
The Interossei dorsales of left hand.
The Interossei volares of left hand.
Transverse section across the wrist and digits.
The anatomical snuffbox,
or radial fossa, (in Latin Foveola radialis),
is a triangular deepening on the radial, dorsal aspect of the hand –at the level of the carpal bones,
specifically, the scaphoid and trapezium bones forming the floor.
The name originates from the use of this surface for placing and then sniffing powdered tobacco, or “snuff.”
Anatomical snuff box
Anatomical snuff box
The boundaries
The medial border of the snuffbox is the tendon of the extensor pollicis longus.
The lateral border tendons, of the extensor pollicis brevis and the abductor pollicislongus.
The proximal border is formed by the styloid process of the radius
The distal border is formed by the approximate apex of the schematic snuffbox isosceles triangle.
The floor of the snuffbox varies depending on the position of the wrist, but both the trapezium and primarily the scaphoid can be palpated.
Deep to the tendons which form the borders of the anatomical snuff box liesthe radial artery,
which passes through the anatomical snuffbox on its course from the normal radial pulse detecting area,to the proximal space in between the first and second metacarpals to contributeto the superficial and deep palmar arches.
The cephalic vein arises within the anatomical snuffbox,
while the dorsal cutaneous branch of the radial nerve can be palpated by stroking along the extensor pollicis longus with the dorsal aspect of a fingernail
Ligaments Of The Upper LimbThe acromio-clavicular ligament joins the acromion process to the clavicle.The coraco-clavicular ligament joins the coracoid process to the clavicle.The coraco-acromial ligament joins the coracoid process to the acromion process.
The ligaments of the shoulder-joint are :1. Capsular. 3. Gleno-humeral.2. Coraco-humeral. 4. Glenoid
The ligaments of the elbow are in the form of a capsule which surrounds the joint on all sides. They are the(1) External lateral, (3) Anterior,(2) Internal lateral, (4) Posterior.
The ligaments of the wrist are the(1) Anterior, (3) Internal lateral,(2) Posterior, (4) External lateral.
Synovial Membrane.—The pisiform, and the upper metacarpal joint of the thumb, have each a separate synovial membrane. The other carpal and metacarpal joints have a single synovial membrane.
Zone I consists of the profundus tendon only and is bounded proximally by the insertion of the superficialis tendons and distally by the insertion of the FDP tendon into the distal phalanx. Zone II is often referred to as "Bunnell's no man's land," . Proximal to zone II, the flexor digitorum superficialis (FDS) tendons lie superficial to the flexor digitorum profundus (FDP) tendons.
Within zone II and at the level of the proximal third of the proximal phalanx,
the FDS tendons split into 2 slips, collectively known as Camper chiasma. These slips then divide around the FDP tendon and reunite on the dorsal
aspect of the FDP, inserting into the distal end of the middle phalanx
The 5 flexor tendon zones in the hand are
Zone III extends from the distal edge of the carpal ligament to the proximal edge of the A1 pulley, Within zone III, the lumbrical muscles originate from the FDP tendons. The distal palmar crease superficially marks the termination of zone III and the beginning of zone II.
Zone IV includes the carpal tunnel and its contents (ie, the 9 digital flexors and the median nerve).
Zone V extends from the origin of the flexor tendons at their respective muscle bellies to the proximal edge of the carpal tunnel.
Retinacular portion of the flexor tendon sheath (pulley system).
Membranous portion of the flexor tendon sheath
Flexor tendons with attached vincula.
The forearm can be divided anatomically into anterior and posterior compartments. The anterior compartment contains the flexor-pronator group of muscles, most of which arise from a common flexor attachment on the medial epicondyle of the humerus.The 8 muscles of the anterior compartment may be divided further into 3 distinct functional groups, as follows: (1) muscles that rotate the radius on the ulna, (2) (2) muscles that flex the wrist, and (3) (3) muscles that flex the digits. The muscles that flex the digits include the flexor digitorum profundus (FDP),
flexor digitorum superficialis (FDS), and the flexor pollicis longus (FPL).
Flexor Muscles of the Digits
The digital flexor sheath is a closed synovial system consisting of both membranous and retinacular portions.The membranous portion comprises visceral and parietal layers that invest the flexor digitorum profundus (FDP) and flexor digitorum superficialis (FDS) tendons in the distal aspect of the hand.
The retinacular component consists of tissue condensations arranged in cruciform, annular, and transverse patterns that overlie the membranous, or synovial, lining.
The digital flexor sheath has been proposed to have a 3-fold function, as follows: (1) it facilitates smooth gliding of the tendons; (2) the retinacular component acts as a fulcrum, adding a mechanical advantage
to flexion;(3) it is a contained system, or bursa, with synovial fluid bathing the tendons and
aiding in their nutrition.
Digital Flexor Sheath
The membranous portion of the sheath appears macroscopically as a number of cul-de-sacs, or plicae, that interdigitate between both the tendons and the retinacular tissue condensations.
The first cul-de-sac is located approximately 10-14 mm proximal to the distal metacarpal head and represents the point of transition between the parietal and visceral layers of synovium.
This outpouching occurs for each separate tendon, in effect forming 2 separate plicae. (Note that this is true only for the middle 3 rays of the hand.
In most instances, both the first- and fifth-digit synovial layers begin much more proximally at the level of the wrist, and are referred to as the radial and ulnar bursa, respectively.)
Distally, the parietal layer of synovium forms plicae between each of the retinacularelements of the pulley system.
The synovium ends distally, forming a final single cul-de-sac prior to the insertion of the FDP tendon on the distal phalanx.
Zone 1 (distal interphalangeal [DIP] joint) Zone 2 (middle phalanx) Zone 3 (proximal interphalangeal [PIP] joint) Zone 4 (proximal phalanx) Zone 5 (metacarpophalangeal [MCP] joint) Zone 6 (dorsum of hand) Zone 7 (wrist) Zone 8 (dorsal forearm)
Extensor TendonZones of hand.
The dorsum of the hand, wrist, and forearm are divided into 8 anatomic zones