Download anatomy of the hand

 ANATOMY OF THE HAND

DR SANTOSH KUMAR

ASSOCIATE PROFESSOR

JINNAH SINDH MEDICAL

UNIVERSITY KARACHI
 Hand function is an important feature in humans over other primates who lack fine control and
precision

EMBRYOLOGY OF THE
UPPER LIMB
 Limb buds first appear as small elevations on ventro lateral body end of fourth week.
 Each limb bud :
 Mesenchyme derived from somatic mesoderm which is covered by a layer of ectoderm
 Distal end of bud form flipper like limbs.
 Later bones develop and myoblast aggregate to develop muscle mass .
 Upper limb rotates laterally 90 degrees
 Specific dermatome ( which is skin area supplied by a single spinal nerve )

ANATOMY
 Bony skeleton
 Muscles and soft tissues
 Vessels and nerves

BONY SKELETON
 Wrist joint composed of multiple carpal bone articulating with the radius proximally and five
metacarpals distally
 Proximal row of carpal bone
, lunate , traquetral , pisiform
 Distal row
hamate

BONES OF THE HAND
(radial to ulnar)
scafoid
trapezium , trapazoid , capitate ,
 5 Metacarpals
 Thumb is no. 1
 Little finger is no. 5

PHALANGES
 All fingers have 3 phalanges
proximal
middle
distal
 Except thumb has 2
proximal
distal
 Most of tendon in the hand originate in muscles arising from the forearm
 Flexor on volar aspect of forearm must arise from common flexor tendon (medial epicondyle )
 Wrist
 Wrist is a joint complex consisting of radio-carpal joint and many relationships between the
carpal bones
 Review of carpals
 Proximal row = Pisiform, Triquetrum, Lunate, and Scaphoid*
 Distal row = Hamate, Capitate, Trapezoid, and Trapezium
 *Scaphoid has a notoriously poor blood supply and recovers poorly following injury
 Osteology
 Osteology
 Osteology
 Scaphoid
 Cross Section at Wrist
 Wrist
 All carpal bones articulate via gliding or plane joints
 A more or less joint exists between proximal row and distal row of bones called mid-carpal –
truly is a series of gliding joints
 Scaphoid, Lunate and Triquetrum with Trapezium, Trapezoid, Capitate and Hamate
 Pisiform is not involved
 Wrist
 True Wrist = Radio-Carpal
•
“Ulnar-Carpal” = interposed disc
 Distal radius with proximal carpals
 Condyloid joint – 2 degrees of freedom
 Major Ligaments
 Palmar radio-carpal, palmar ulnocarpal, dorsal radio-carpal, dorsal ulno-carpal, radial and ulnar
collateral
 Radio-Carpal
 Ligaments
 Ligaments
 Wrist
 Mid-Carpal
 Proximal row of carpals with distal row
 A series of gliding joints
 MAJOR Ligaments – Capsule plus
 Pisohamate, pisometacarpal, capitotriquetral, palmar and dorsal carpometacarpal
 Ligaments
 Wrist
 Movements
 Flexion/Extension – about 70-80 degrees of ROM
•
Radiocarpal v. Mid Carpal
•
Flexion is initiated in mid carpal joint and 60% occurs there
•
Extension is also initiated at mid carpal but most occurs in radio-carpal. Need 35 degrees
for good function – at least 10 for any significant function.
 Abduction/Adduction – about 15 to 20 degrees
•
Intercarpal – proximal row slides over distal row
 Movements
 Movements
 Movements
 Carpo-Metacarpal Joints
 2-5
•
Hamate with 4 and 5
•
Capitate with 3
•
Trapezoid with 2
 Gliding joints with limited range – mostly passive
 Palmar and Dorsal carpometacarpal ligaments
 C-M Joints
 C-M Joints
 C- M Thumb
 Trapezium with 1st met
 Saddle
 Adds rotary component – very mobile
 Capsule support
 C-M Thumb
 Metacarpal – Phalangeal Joints
 Ellipsoid
 Passive rotation
 Collateral Ligaments
 Deep Transverse Metacarpal Ligaments
 Palmar Ligaments (Plates)
 Ligaments
 Ligaments
 Interphalangeal Joints
 Hinge
 Collateral Ligaments
 Palmar Ligaments (Plates)
 Ligaments
 Definition of Finger Movements
 Reference is imaginary line through the middle of long (3rd) finger
 Adduction of 2-5 = towards that point
 Abduction = away –1, 4, and 5
 Thumb
•
Flexion
•
Extension
•
ABD
•
ADD
•
Rotation
•
Opposition = flexion with adduction and rotation
 Finger Movements
 Finger Movements
 Flexor Tendons
 Tenosynovium (AKA Fibro-Osseous Tunnels)
 Anular Pulleys AKA Vaginal Ligaments
•
Anular and Cruciform
•
Relationship to Palmar Plates
 Vinculum Longa and Breve