Level

Semester
Module (..)
The hand
INSTRUCTOR INFORMATION
• Name: Reham Atef
• Department: Anatomy
• Office hours: sunday.
 ‫‪Mission and Vision of Faculty‬‬
‫رسالة الكلية‪:‬‬
‫تلتزم كلية الطب البشري – جامعة الدلتا للعلوم والتكنولوجيا بتقدیم برنامج تعليمي تكاملي متميز یقوم‬
‫على المھـارة والمعرفـة ویھـدف الى تخریج أطبـاء قـادرین على الوفـاء بواجبـاتھم المھنيـة واألخالقيـة‪،‬‬
‫والتعليم الطبي المستمر والمشاركة الفعالة في البحث العلمي وخدمة المجتمع‪.‬‬
‫رؤیة الكلية‪:‬‬
‫تسعى كلیة الطب البشري ‪ -‬جامعة الدلتا للعلوم والتكنولوجیا من خالل تطبیق برنامج التعلم القائم على‬
‫اكتســاب الجدارات أن تكون في مقدمة المؤسسات الطبیة التعلیمیة المتمیزة على المستوى المحلي‬
‫والقومى والعالمي‪.‬‬
The deep fascia of the Hand
 Deep fascia
Flexor & Extensor Retinaculae
• Bands of Deep Fascia
• Function:
• Hold the long flexor and
extensor tendons in position
at the wrist.
• Attachments:
• Medially
• both attached to Pisiform &
Hook of Hamate.
• Laterally:
• Flexor Retinaculum to
Scaphoid & Trapezium.
• Extensor Retinaculum to
Distal end of Radius
• Structures pass superficial to the flexor
retinaculum
• Flexor carpi ulnaris
• Ulnar nerve
• Ulnar artery
• Palmar cutaneous branch of ulnar
nerve
• Palmaris longus
• Palmar cutaneous branch of median
nerve

• Structures pass deep to the flexor

retinaculum
• FDS & FDP
• Median nerve
• FPL
• Flexor carpi radialis

Medial to Lateral
• Structures pass super cial to the
extensor retinaculum
• Dorsal cutaneous branch of the ulnar
nerve
• Basilic vein
• Cephalic vein
• Super cial branch of the radial nerve

• The following structures pass beneath

the extensor retinaculum
• Extensor carpi ulnaris
• Extensor digiti minimi
• Extensor digitorum and extensor indicis

Medial to Lateral
Carpal Tunnel

• Definition
• Is fibro-osseous tunnel formed by the
concave anterior surface of the carpal
bones & close by the flexor retinaculum

• Contents
• (Structures Beneath Flexor Retinaculum
• Flexure digitorum superficialis &
profundus
• Median nerve
• Flexor carpi radialis
Capal tunnel Syndrome
• Definition:
• Compression of the median nerve with in the carpal tunnel
called carpal tunnel syndrome
• Causes:
• The exact cause of the compression is unknown but the
thickening of the synovial sheaths of the flexor tendons or
arthritic changes in carpal are responsible in many cases
• Manifestations:
• Burning pain “pins & needles” in the lateral 3 1/2 fingers.
• Weakness or atrophy of the thenar muscles Ape Hand.
• Inability to oppose the thumb.
• No parethesia over the thenar eminence

The condition is relieved by decompressing the

tunnel by making a longitudinal incision through
flexor retinaculum
Palmar Aponeurosis

• Thickened deep fascia of the hand

• Triangular in shape
• Occupies the central area of the palm
• The apex is attached to the distal border of
flexor retinaculum and receives the insertion of
palmaris longus tendon.
• Base divides at the bases of the fingers into four
slips that pass into the fingers

• Functions:
• Gives firm attachment to the overlying skin and
improves the grip.
• Protects the underlying tendons, vessels & nerves.
Small Muscles of the Hand
• The small muscles of the hand include the
• four lumbrical muscles,

• the eight interossei muscles,

• the short muscles of the thumb,

• and the short muscles of the little finger

Palmar Interossei
• Origin
• 1st – ulnar side base of 1st metacarpal bone
• 2nd – ulnar side of 2nd MC bone
• 3rd – radial side of 4th MC bone
• 4th – radia side of 5th MC bone
• Insertion
• Extensor expansion of 2,4 and 5th digits
• N. supply
• Ulnar
• action
• ADD of 1st, 2nd, 4th and 5th digits toward
midline of hand
 Dorsal Interossei
• Origin
• 1st lateral head – ulnar side of 1st metacarpal
bone
• 1st medial head – radial side of 2nd metacarpal
bone
• 2nd, 3rd, 4th space between metacarpal bones
• Insertion
• 1st – radial side 2nd proximal phalanx
• 2nd – radial side of 3rd
• 3rd – ilnar side of 3rd
• 4th – ulnar side of 4th
• N.supply
• Ulnar
• action
• ABD of 2nd, 3rd, and 5th finger from midline
Lumbricales
• Origin
• Tendons of FDP
• Insertion
• Extensor expansion on dorsal aspect of
each digits radial side
• N.supply
• 1 and 2 – median
• 3 and 4 – ulnar
• Action
• MCP flexion 2-5 digits
• DIP & PIP ext 2-5 digits
Figure 3 - The lumbricals of the hand. Note the differing unipennate and bipennate structure.
Palmaris Brevis
• Origin
• Flexor retinaculum
• Insertion
• Palmar surface skin on ulnar side of
hand
• N.supply
• Ulnar
• action
• Wrinkles skin of hand on ulnar side
The short muscles of the thumb
are the abductor pollicis brevis,
the flexor pollicis brevis, the Thenar Eminance

opponens pollicis, and the

adductor pollicis

The first three of these muscles

form the thenar eminence.
Adductor Pollicis
• Origin
• Oblique Head
• Capitate bone
• Bases of 2-3 metacarpals
• Transverse Head
• Proximal 2/3 of palmar surface of 3rd
metacarpal
• Insertion
• Ulnar side of base of 1st proximal phalanx
• N.supply
• Ulnar
• Action
• CMC ADD of thumb
Abductor Pollicis Brevis
• Origin
• Scaphoid tuberosity
• Trapezium ridge
• Transverse carpal ligament
• Insertion
• Lateral base f proximal 1st phalanx
• N.supply
• Median
• Action
• CMC & MCP ABD of thumb
Flexor Pollicis Brevis
• Origin
• Superficial head – trapezium
• Deep head – trapezoid,
capitate and palmar ligaments
of distal carpal bones
• Insertion
• Base of prximal 1st phalanx on
radial side
• Extensor expansion
• N.supply
• Superficial – median
• Deep – Ulnar
• Action
• CMC & MCP Flexion of thumb
Opponens Pollicis
• Origin
• Trapezium
• Transverse Carpal
Ligament
• Insertion
• Radial side of 1st
metacarpal shaft
• N.supply
• Median
• Action
• Opposition
Short Muscles of the Little Finger
• The short muscles of the little finger are the abductor digiti minimi, the flexor
digiti minimi brevis, and the opponens digiti minimi, which together form the
hypothenar eminence

• The opponens digiti minimi muscle is only capable of rotating the fifth metacarpal
bone to a slight degree

• However, it assists the flexor digiti minimi in flexing the carpometacarpal joint of
the little finger

• thereby pulling the fifth metacarpal bone forward and cupping the palm.
Intrinsic Hand Muscles
Hypothenar Eminence
Abductor Digiti Minimi
• Origin
• Pisiform
• Insertion
• Ulnar side base of 5th proximal
phalanx
• N.supply
• Ulnar
• Action
• MCP ABD of 5th digit
Opponens Digiti Minimi
• Origin
• Hook of hamate
• Transverse carpal ligament
• Insertion
• Ulnar border of entire 5th metacarpal bone
• N.supply
• Ulnar
• Action
• MCP flexion & rotation of 5th digit
Flexor Digiti Minimi
• Origin
• Hamate bone
• Transverse carpal ligament
• Insertion
• Ulnar side of proximal 5th phalanx
• N.supply
• Ulnar
• Action
• MCP Flexion of 5th digit
 Arteries of the Palm
• Ulnar Artery

• The ulnar artery enters the hand anterior to the flexor

retinaculum on the lateral side of the ulnar nerve and the
pisiform bone
• The artery gives off a deep branchand then continues into
the palm as the superficial palmar arch.
• The superficial palmar arch is a direct continuation of the
ulnar artery
• On entering the palm, it curves laterally behind the palmar
aponeurosis and in front of the long flexor tendons
• The arch is completed on the lateral side by one of the
branches of the radial artery
• The curve of the arch lies across the palm, level with the
distal border of the fully extended thumb
• The deep branch of the ulnar artery arises in front of the
flexor retinaculum, passes between the abductor digiti
minimi and the flexor digiti minimi
• joins the radial artery to complete the deep palmar arch
• Radial Artery

• On entering the palm, it curves medially between the oblique and

transverse heads of the adductor pollicis and continues as the deep
palmar arch
• The deep palmar arch is a direct continuation of the radial artery
• It curves medially beneath the long flexor tendons and in front of the
metacarpal bones and the interosseous muscles

• The arch is completed on the medial side by the deep branch of the
ulnar artery

• The curve of the arch lies at a level with the proximal border of the
extended thumb.

• The deep palmar arch sends branches superiorly, which take part in
the anastomosis around the wrist joint, and inferiorly, to join the
digital branches of the superficial palmar arch.
Veins of the Palm
• Superficial and deep palmar arterial arches are
accompanied by superficial and deep palmar
venous arches, receiving corresponding tributaries.
 Dorsal Venous Arch
• The dorsal venous arch lies in the subcutaneous
tissue proximal to the metacarpophalangeal
joints

• drains on the lateral side into the cephalic vein

and, on the medial side, into the basilic vein

• the greater part of the blood from the whole

hand drains into the arch, which receives digital
veins

• freely communicates with the deep veins of the

palm through the interosseous spaces.
 Nerves of the Palm
• Median Nerve
• The median nerve enters the palm by passing behind the flexor retinaculum
and through the carpal tunnel.
• It immediately divides into lateral and medial branches
• The muscular branch takes a recurrent course around the lower border of
the flexor retinaculum and lies about one fingerbreadth distal to the tubercle
of the scaphoid
• it supplies the muscles of the thenar eminence (the abductor pollicis brevis,
the flexor pollicis brevis, and the opponens pollicis) and the first lumbrical
muscle.
• The cutaneous branches supply the palmar aspect of the lateral three and a
half fingers and the distal half of the dorsal aspect of each finger
• One of these branches also supplies the second lumbrical muscle.
• the palmar cutaneous branch of the median nerve given off in the front of
the forearm
• crosses anterior to the flexor retinaculum and supplies the skin over the
lateral part of the palm
 Ulnar Nerve
• The ulnar nerve enters the palm anterior to the flexor retinaculum alongside
the lateral border of the pisiform bone
• As it crosses the retinaculum it divides into a superficial and a deep terminal
branch.
• The superficial branch of the ulnar nerve descends into the palm,
lying in the subcutaneous tissue between the pisiform bone and the hook of
the hamate
• The ulnar artery is on its lateral side. Here, the nerve and artery may lie in a
fibro-osseous tunnel, the tunnel of Guyon, created by fibrous tissue derived
from the superficial part of the flexor retinaculum

• The nerve may be compressed at this site, giving rise to clinical signs and
symptoms.
• The nerve gives off the following branches:
• a muscular branch to the palmaris brevis
• cutaneous branches to the palmar aspect of the medial side of the little
finger and the adjacent sides of the little and ring fingers
• It also supplies the distal half of the dorsal aspect of each finger.
 Deep Branch of the Ulnar Nerve
• The deep branch of the ulnar nerve runs backward between the abductor digiti minimi and the
flexor digiti minimi

• It pierces the opponens digiti minimi, winds around the lower border of the hook of the hamate,
and passes laterally within the concavity of the deep palmar arch.

• The nerve lies behind the long flexor tendons and in front of the metacarpal bones and interosseous
muscles

• It gives off muscular branches to the three muscles of the hypothenar eminence

• the abductor digiti minimi, the flexor digiti minimi, and the opponens digiti minimi.

• It supplies all the palmar and dorsal interossei, the third and fourth lumbrical muscles, and both
heads of the adductor pollicis muscle.
 The Dorsum of the Hand
• The skin on the dorsum of the hand is thin, hairy, and freely
mobile on the underlying tendons and bones.

• The sensory nerve supply to the skin on the dorsum of the

hand is derived from the superficial branch of the radial nerve
and the posterior cutaneous branch of the ulnar nerve.

• The superficial branch of the radial nerve winds around the

radius deep to the brachioradialis tendon, descends over the
extensor retinaculum, and supplies the lateral two thirds of
the dorsum of the hand

• divides into several dorsal digital nerves that supply the

thumb, the index and middle fingers, and the lateral side of
the ring finger

• The area of skin on the back of the hand and fingers supplied
by the radial nerve is subject to variation

• Frequently, a dorsal digital nerve, a branch of the ulnar nerve,

also supplies the lateral side of the ring finger
• The posterior cutaneous branch of the ulnar nerve winds around the ulna deep to the flexor
carpi ulnaris tendon

• descends over the extensor retinaculum, and supplies the medial third of the dorsum of the
hand

• It divides into several dorsal digital nerves that supply the medial side of the ring and the sides
of the little fingers

• The dorsal digital branches of the radial and ulnar nerves do not extend far beyond the
proximal phalanx

• The remainder of the dorsum of each finger receives its nerve supply from palmar digital
nerves.