The document discusses congenital hand anomalies, beginning with definitions and embryology. It describes how hand development begins in the 4th week after fertilization and is guided by three signaling centers. Classification systems for congenital hand anomalies are discussed, including Swanson's classification which is based on embryologic origin and morphology. The types of anomalies covered include failure of formation (transverse arrest, longitudinal arrest, radial/ulnar club hand, cleft hand), failure of differentiation (syndactyly), and duplication (polydactyly). Specific examples and classifications of different anomalies are provided.
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TABLE OF CONTENTS
What do these words mean?
Congenital, hand, anomaly
DEFINITIONS
01
When it begins, where, stages
and the centers of control
EMBRYOLOGY
The critical importance of
the hand
INTRODUCTION
02
Swanson’s….
CLASSIFICATIONs
04
AND REVISION
CONCLUSIONS
06
Sydactly, polydactyly,
camptodactyly…etc
EXAMPLES
05
3. “Structural or functional anomalies that
occur during intrauterine life.”
Also called: birth defects, congenital
anomalies, or malformations
Define “Congenital”:
“
4. About the
Humans are distinct from other primates by the
miraculous structure of the hand.
HAND
27 degrees of freedom and its opposing thumb, the hand
is a highly developed and complex grasping organ
the hand also features a highly specific sensory and
tactile organ that human beings use to perceive and
assess themselves and their surroundings
5. In total, there are 27 bones
with 36 articulations and 39
active muscles.
6. Epidemiology
Intgrated team approach, the surgeon,
the therapist and the perants
The deformity is minor
with no functional deficit
1 of every 626
Most cases
Needs an
Of live births and often associated
with other abnormalities
7. Why ?
40%-50% are of unknown causes
The remainder are due to genetic
abnormalities or tertogenetics
genetic abnormalities: single gene,
multiple and chromosomal disorders
The aetiology
10. The embryology
Under guidance of three signaling centers:
1. AER (apical ectodermal ridge) - proximo-distal.
2. ZPA (zone of polarizing activity) - antero-posterior growth.
3. NRE (non ridge ectoderm)(wing less type) - dorsoventral growth
11. THE EMBRYOLGY
The limb bud on the ventrolateral wall of the embryo on day 26
The AER and PZ work as a functional unit responsible for
the outgrowth of the limb along the proximodistal axis
Also known as Wolff crest
the apical ectodermal ridge (AER) developes on the ventromedial
border and is vital in axis orientation, outgrowth, and digitation
It covers a layer of undifferentiated, proliferating mesenchymal cells,
known as the progress zone (PZ), vital in limb outgrowth
12. VASCULAR
THE EMBRYOLGY
The limb bud consists of a mesoderm core covered by ectoderm
The mesoderm will differentiate into bone, cartilage and tendon
The limb bud is initially supplied by a capillary network
This network coalesces into a main artery and a marginal vein
The artery becomes the subclavian-axillary-brachial axis
The brachial becomes interosseous and median arteries
The median artery provides the main blood supply to the hand
Replaced by ulnar and radial around day 44
13. THE EMBRYOLGY
The limb bud continues to grow outward from the ventral, and at day 32= 4
weeks it develops a intoa paddle-shaped hand plate
The mesenchymal cells at 5th week condense in a proximal-to-distal fashion
to form blastemas, which develop into cartilaginous models.
During the 6th week, hyaline cartilage models of the proximal bones of the
extremity are formed
In the 7th week, the upper extremity continues outgrowth and
rotates 90° so that the elbows project posteriorly and the
developing hands lie on the anterior thorax
Cartilaginous models of the bones are undergoing ossification
14. The embryology
Under guidance of three signaling centers:
1. AER (apical ectodermal ridge) - proximo-distal.
2. ZPA (zone of polarizing activity) - antero-posterior growth.
3. NRE (non ridge ectoderm)(wing less type) - dorsoventral growth
15. The embryology
A brief timetable of hand development
Onset of development of arm bud - 27 days=4th
Well-developed arm bud - 28-30 days
Elongation of arm bud - 34-36 days
Formation of hand paddle - 34-38 days=5th wk
Onset of finger separation - 38-40 days
Full separation of fingers - 50-52 days=8th
-- skin creases and moves at the 9th
16. When 3 or more minor anomalies exist in
a single patient, the chance of the
presence of a major anomaly is 90%
—SOMETHING ABOUT THE ANOMALIES
17. Developmentalists have designated the following 3
types of sequences:
Malformation sequence
Deformation sequence
Disruption sequence
—SOMETHING ABOUT THE ANOMALIES
20. Why The SWANSON?
Accepted by IFSSH &
ASSH
Accepted
Expanded by Knight & Kay
in 2000, & Upton in 2006
Expanded
Based on their embryologic
origin & morphological
appearance
Based
21. CLASSIFICATION OF SWANSON
Failure of formation of parts
Failure of differentiation or separation of parts
Duplication
Overgrowth
Undergrowth
Congenital constriction ring syndrome
Generalized skeletal abnormalities &
syndromes
22. Failure of
formation
of parts Transverse arrest
TYPE A
Longitudinal arrest
TYPE B
radial club hand (pre-axial arrest)
ulnar club hand (post-axial arrest)
cleft hand (central arrest)
phocomelia
23. Failure of
formation
of parts
Transverse arrest
TYPE A
Congenital transverse arrest
Rare, Sporadic / environmental.
Level defined by skeletal absence.
Commonly at level of proximal forearm.
Defect in AER signaling
Lt > Rt
Most will not require surgery, but benefited
from prosthesis if referred early
2 groups:
defect in limb formation
Intrauterine amputation after limb formation
24. Failure of
formation
of parts
Longitudinal arrest
TYPE B
Phocomelia (seal limb)
Intercalary arrest
Intervening segment of limb is absent (arm/forearm)
Thalidomide in 1st trimester
Type I (complete) - hand directly attached to trunk
Type II (proximal) – short forearm attached to trunk.
Type III (distal) – short humerus attached to hand.
Surgery – very little role
25. Radial ray dysplasia
Radial club hand/Preaxial
deficiency/Longitudinal radial deficiency
Radially deviated, flexed hand with pronated
and shortened forearm.
Deficient thumb ray & carpal bones (scaphoid
& trapezium), radial nerve.
Normal ulnar two digits
Commonly associated with syndromes
(e.g. VATER, TAR, Holt oram)
M>F
27. Ulnar ray dysplasia
Rarest of longitudinal ray deficiency.
Association with syndromes – uncommon
Disruption of ZPA signaling.
Short,bowed radius with a hypoplastic or
absent ulna.
severely affected (with a relatively stable
wrist).
M>F
Rarest
Elbow
Ulnar club hand /Postaxial deficiency
28. Ulnar ray dysplasia
Bayne classification
I – Ulnar hypoplasia
II – Partial ulnar aplasia
III- Total ulnar aplasia
IV – Radiohumeral synostosis
Paley & Herzenberg classification
I – Ulnar hypoplasia with intact distal epiphysis
II – Partial ulnar aplasia (distal 1/3rd )
III – Partial ulnar aplasia (distal= 2/3rd )
IV – Total ulnar aplasia
V – Radiohumeral synostosis
Ulnar club hand /Postaxial deficiency
30. Central ray deficiency /cleft hand
Most common longitudinal deficiency.
Defect in AER signaling.
B/L (frequently).
Structures proximal to wrist – normal.
Little finger – always present
Associated syndactyly & narrow web space.
Complex syndactyly (thumb & index) – in severe case.
Hand – “functionally good but aesthetically a disaster‟‟.
Association with cleft feet in 1/3rd cases (SHSF)
Other Syndromic associations: EEC syndrome(ectrodactyly, ectodermal
dysplasia,
32. Mansker’s classification
of cleft hand
Type I – Normal 1st web
Type II
A – mildly narrowed web
B – severely narrowed
Type III – Syndactylised web
Type IV – Merged web
Type V – Absent web
A – Partial suppression of radial ray
B – Complete suppression of radial ray
33. Failure of
differentiation
of parts
Failure of differentiation or separation of parts
One of the most common congenital
hand malformations.
3rd web > 4th web > 2nd web
Association – Poland, Apert syndrome.
Complicated syndactyly –
More than only distal bony fusion
Abnormal bone structure inside .
(fusion ,missing bone, abnormal joints,
rudimentary bones ,cross bones)
Seen in Apert syndrome,
Central synpolydactyly
Syndactyly
35. Developmentalists have designated the following 3
types of sequences:
Malformation sequence
Deformation sequence
Disruption sequence
—Modified classification of congenital…
Editor's Notes
AER the critical, truncated limb, if earlier= more proximal limb truncation…..produces FGF 2,4,8
ZPA ulna and little in one side and the thumb and radius on the other= radioulnar
Required to maintain AER
NRE ventral and dorsal if removed gives 2 palmar or 2 dorsal aspects
From 4th to 9th
At 4th the arm bud starts, 8th – 10th somaites
Hand paddle at 5th
Separation at 5th
Under 3 zones direction
As understanding of the pathogenesis has developed, the shortcomings have become evident
Example: brachysyndactyly and symbrachydactyly= atypical cleft hand…. Can not be differentiated
Swansons noted” they could be placed either in cat I or II” but also because it has hypoplasia and undergrowth= cat V
Ifssh
Each one of them is subdivided into:
1- failure in axis of of formation and differentiation od the entire limb
2- ……………………………………………………………………… ….. Hand plate
3- failure in hand plate formation and diffrerntiation