Musculoskeletal System - Limb Abnormalities: Difference between revisions

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[[File:Stage20-23_limbs_b.jpg|500px|right]]
{{Header}}[[File:Stage20-23_limbs_b.jpg|500px|right]]
== Introduction ==
== Introduction ==
[[File:Appendicular_skeleton.jpg|thumb|right|Adult appendicular skeleton]]
[[File:Appendicular_skeleton.jpg|thumb|200px|alt=Adult appendicular skeleton|Adult appendicular skeleton]]
Musculoskeletal and limb abnormalities are one of the largest groups of congenital abnormalities. The upper and lower limbs have a large number of different genetic and environment derived abnormalities, some of which can be surgically repaired, while others may indicate other syndromes or karyotype anomalies (trisomy etc) by association. Many of the hand and foot abnormalities are described as "dactyly" from the Greek (''daktulos'') for finger or digit.
Musculoskeletal and limb abnormalities are one of the largest groups of congenital abnormalities. The upper and lower limbs have a large number of different genetic and environment derived abnormalities, some of which can be surgically repaired, while others may indicate other syndromes or karyotype anomalies (trisomy etc) by association. Congenital limb agenesis and deficiencies prevalence is about 7.9/10,000 live births.  


A 1994 review of data from Hungary (1975-1984)<ref><pubmed>8172251</pubmed></ref> showed in this population an overall 1 in 1,816 prevalence of limb deficiency at birth.


A key historic area of limb abnormalities were those associated with limb reduction (and other defects) with the "morning sickness" prescription drug Thalidomide and its significant teratogenic effects (More? [[Abnormal Development - Thalidomide]]).  
<center>Hand and foot abnormalities are often described as different forms of "dactyly" from the Greek (''daktulos'') for finger or digit.</center>


{{Template:Musculoskeletal Links}} | [[Abnormal Development - Thalidomide|Thalidomide]]


A key historic area of limb abnormalities were those associated with limb reduction (and other defects) with the "morning sickness" prescription drug Thalidomide and its significant teratogenic effects (More? [[Abnormal Development - Thalidomide|'''Thalidomide''']]).
A 1994 review of data from Hungary (1975-1984){{#pmid:8172251|PMID8172251}} showed in this population an overall 1 in 1,816 prevalence of limb deficiency at birth.
{{Musculoskeletal Links}}
==Some Recent Findings==
==Some Recent Findings==
[[File:France - Ain - Brittany - Loire-Atlantique.jpg|thumb|200px|alt - French Map regions Ain, Brittany and Loire-Atlantique|French regions - Ain, Brittany and Loire-Atlantique]]
{|
{|
|-bgcolor="F5FAFF"  
|-bgcolor="F5FAFF"  
|
|
* '''Triphalangeal thumb-polysyndactyly syndrome and syndactyly type IV are caused by genomic duplications'''<ref><pubmed>18417549</pubmed></ref> "Both Triphalangeal thumb-polysyndactyly syndrome (TPTPS) and syndactyly type IV (SD4) are due to duplications involving ZPA regulatory sequence (ZRS), the limb-specific Sonic hedgehog (SHH) enhancer. Point mutations in the ZRS and duplications encompassing the ZRS cause distinctive limb phenotypes."  
* '''Limb Agenesis''' - France has launched a national investigation into the number of babies being born with entire missing upper limbs, missing forearms and hands, or fingers just weeks after an initial inquiry closed. The cases were clustered in the Ain, Brittany and Loire-Atlantique regions. The cause is still unknown, but may relate to local [[Abnormal_Development_-_Environmental|developmental environmental abnormalities]]. (More? [[Musculoskeletal System - Limb Abnormalities|Limb Abnormalities]] | [https://www.bbc.com/news/world-europe-46043564 BBC News - French Ain babies Missing limb births prompt national inquiry])
 
* '''Review of triphalangeal thumb'''{{#pmid:30318985|PMID30318985}} "Despite being a rare congenital limb anomaly, triphalangeal thumb is a subject of research in various scientific fields, providing new insights in clinical research and evolutionary biology. The findings of triphalangeal thumb can be predictive for other congenital anomalies as part of an underlying syndrome. Furthermore, triphalangeal thumb is still being used as a model in molecular genetics to study gene regulation by long-range regulatory elements. We present a review that summarizes a number of scientifically relevant topics that involve the triphalangeal thumb phenotype. Future initiatives involving multidisciplinary teams collaborating in the field of triphalangeal thumb research can lead to a better understanding of the pathogenesis and molecular mechanisms of this condition as well as other congenital upper limb anomalies." See also {{#pmid:330223699|PMID30223699}}
 
* '''Prenatal exposure to environmental factors and congenital limb defects'''{{#pmid:27768243|PMID27768243}} "Limb congenital defects afflict approximately 0.6:1000 live births. In addition to genetic factors, prenatal exposure to drugs and environmental toxicants, represents a major contributing factor to limb defects. Examples of well-recognized limb teratogenic agents include thalidomide, warfarin, valproic acid, misoprostol, and phenytoin. While the mechanism by which these agents cause dymorphogenesis is increasingly clear, prediction of the limb teratogenicity of many thousands of as yet uncharacterized environmental factors (pollutants) remains inexact."
 
* '''Role of Genetic Factors in the Pathogenesis of Radial Deficiencies in Humans'''{{#pmid:26962299|PMID26962299}} "Radial deficiencies (RDs), defined as under/abnormal development or absence of any of the structures of the forearm, radial carpal bones and thumb, occur with a live birth incidence ranging from 1 out of 30,000 to 1 out 6,000 newborns and represent about one third/one fourth of all the congenital upper limb anomalies. About half of radial disorders have a mendelian cause and pattern of inheritance, whereas the remaining half appears sporadic with no known gene involved. In sporadic forms certain anomalies, such as thumb or radial hypoplasia, may occur either alone or in association with systemic conditions, like vertebral abnormalities or renal defects. All the cases with a mendelian inheritance are syndromic forms, which include cardiac defects (in Holt-Oram syndrome), bone marrow failure (in Fanconi anemia), platelet deficiency (in thrombocytopenia-absent-radius syndrome), ocular motility impairment (in Okihiro syndrome)."
|}
{| class="wikitable mw-collapsible mw-collapsed"
! More recent papers &nbsp;
|-
| [[File:Mark_Hill.jpg|90px|left]] {{Most_Recent_Refs}}


* '''A t(4;6)(q12;p23) translocation disrupts a membrane-associated O-acetyl transferase gene (MBOAT1) in a patient with a novel brachydactyly-syndactyly syndrome'''<ref><pubmed>17440500</pubmed></ref> "One of the genes on chromosome 6, the membrane-associated O-acetyl transferase gene 1 (MBOAT1), was disrupted by the breakpoint. ...Identification of the transferred acyl group and the target may reveal the signaling pathways altered in this novel brachydactyly-syndactyly syndrome."
Search term: [http://www.ncbi.nlm.nih.gov/pubmed/?term=Abnormal+Limb+Development ''Abnormal Limb Development'']


* '''Characterization of a novel ectodermal signaling center regulating Tbx2 and Shh in the vertebrate limb'''<ref><pubmed>17300775</pubmed></ref> "The data presented here identify the non-AER border of dorsal-ventral ectoderm as a new signaling center in limb development that localizes the ZPA to the limb margin. This finding explains the tight restriction of Shh expression to the posterior margin throughout limb outgrowth as well as the tight restriction of Shh expression to the anterior margin in many mutants exhibiting preaxial polydactyly."
<pubmed limit=5>Abnormal Limb Development</pubmed>
|}
{| class="wikitable mw-collapsible mw-collapsed"
! Older papers &nbsp;
|-
| {{Older papers}}
 
* '''Sirenomelia phenotype in bmp7;shh compound mutants: a novel experimental model for studies of caudal body malformations'''{{#pmid:23028704|PMID23028704}} "Sirenomelia is a severe congenital malformation of the lower body characterized by the fusion of the legs into a single lower limb. This striking external phenotype consistently associates severe visceral abnormalities, most commonly of the kidneys, intestine, and genitalia that generally make the condition lethal. Although the causes of sirenomelia remain unknown, clinical studies have yielded two major hypotheses: i) a primary defect in the generation of caudal mesoderm, ii) a primary vascular defect that leaves the caudal part of the embryo hypoperfused.  ...We show that the signaling defect predominantly impacts the morphogenesis of the hindgut and the development of the caudal end of the dorsal aortas. The deficient formation of ventral midline structures, including the interlimb mesoderm caudal to the umbilicus, leads to the approximation and merging of the hindlimb fields."
 
* '''Triphalangeal thumb-polysyndactyly syndrome and syndactyly type IV are caused by genomic duplications'''{{#pmid:18417549|PMID18417549}} "Both Triphalangeal thumb-polysyndactyly syndrome (TPTPS) and syndactyly type IV (SD4) are due to duplications involving ZPA regulatory sequence (ZRS), the limb-specific Sonic hedgehog (SHH) enhancer. Point mutations in the ZRS and duplications encompassing the ZRS cause distinctive limb phenotypes."
 
* '''A t(4;6)(q12;p23) translocation disrupts a membrane-associated O-acetyl transferase gene (MBOAT1) in a patient with a novel brachydactyly-syndactyly syndrome'''{{#pmid:17440500|PMID17440500}} "One of the genes on chromosome 6, the membrane-associated O-acetyl transferase gene 1 (MBOAT1), was disrupted by the breakpoint. ...Identification of the transferred acyl group and the target may reveal the signaling pathways altered in this novel brachydactyly-syndactyly syndrome."
 
* '''Characterization of a novel ectodermal signaling center regulating Tbx2 and Shh in the vertebrate limb'''{{#pmid:17300775|PMID17300775}} "The data presented here identify the non-AER border of dorsal-ventral ectoderm as a new signaling center in limb development that localizes the ZPA to the limb margin. This finding explains the tight restriction of Shh expression to the posterior margin throughout limb outgrowth as well as the tight restriction of Shh expression to the anterior margin in many mutants exhibiting preaxial polydactyly."
|}
|}


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==Developmental Dysplasia of the Hip==
==Developmental Dysplasia of the Hip==
[[File:Congenital dislocation hip.jpg|thumb|X-Ray Developmental Dysplasia of the Hip]]
 
[[File:Acetabular angle.jpg|thumb|Acetabular angle<ref name="PMID15958160"><pubmed>15958160</pubmed>| [http://www.biomedcentral.com/1471-2431/5/17 BMC Pediatr.]</ref>]]
For more details see [[Developmental Hip Dysplasia]].
 
{| class="wikitable mw-collapsible mw-collapsed"
! [[International_Classification_of_Diseases|ICD-10]] &nbsp;
|-
| [[International_Classification_of_Diseases|ICD-10]] [[International_Classification_of_Diseases_-_XVII_Congenital_Malformations#Congenital_malformations_and_deformations_of_the_musculoskeletal_system_.28Q65-Q79.29|Q65 Congenital deformities of hip]] Excl.: clicking hip (R29.4)
|-
| Q65 Congenital deformities of hip
 
Excl.: clicking hip (R29.4)
 
* Q65.0 Congenital dislocation of hip, unilateral
* Q65.1 Congenital dislocation of hip, bilateral
* Q65.2 Congenital dislocation of hip, unspecified
* Q65.3 Congenital subluxation of hip, unilateral
* Q65.4 Congenital subluxation of hip, bilateral
* Q65.5 Congenital subluxation of hip, unspecified
* Q65.6 Unstable hip Dislocatable hip Subluxatable hip
* Q65.8 Other congenital deformities of hip Anteversion of femoral neck Congenital acetabular dysplasia Congenital coxa: valga vara
* Q65.9 Congenital deformity of hip, unspecified
|}
{| class="wikitable mw-collapsible mw-collapsed"
! [[International_Classification_of_Diseases#International_Classification_of_Diseases_11_.28ICD11.29|ICD-11 beta]] - LB74&nbsp;
|-
!  LB74 Structural developmental anomalies of pelvic girdle 
|-
| Exclusions - Clicking hip (MG40)
|-
|
* LB74.1 Developmental dysplasia of hip 
* LB74.2 Congenital subluxation of hip 
* LB74.3 Unstable hip 
* LB74.4 Congenital coxa vara 
* LB74.5 Congenital coxa valga 
* LB74.6 Wide symphysis pubis 
* LB74.Y Other specified structural developmental anomalies of pelvic girdle 
* LB74.Z Structural developmental anomalies of pelvic girdle, unspecified 
|}
 
{|
| [[File:Congenital dislocation hip.jpg|300px]]
| [[File:Renal agenesis 01.jpg|300px]]
|-
| X-Ray Hip Dysplasia
| X-Ray Hip Dysplasia and renal agenesis{{#pmid:20388228|PMID20388228}}
|}
 
[[File:Acetabular angle.jpg|thumb|Acetabular angle{{#pmid:15958160|PMID15958160}}]]
<br>
Also called Congenital Hip Dislocation.
Also called Congenital Hip Dislocation.
* Instability: 1:60 at birth;  1:240 at 1 wk: Dislocation untreated; 1:700
* Instability: 1:60 at birth;  1:240 at 1 wk: Dislocation untreated; 1:700
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* familial predisposition female predominance
* familial predisposition female predominance
* Growth of femoral head, acetabulum and  innominate bone are delayed until the femoral head  fits firmly into the acetabulum
* Growth of femoral head, acetabulum and  innominate bone are delayed until the femoral head  fits firmly into the acetabulum


===Barlow test===
===Barlow test===
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===Ortolani test===
===Ortolani test===
Ortolani maneuver) A clinical term to describe a physical examination of the newborn for [[D#developmental dysplasia of the hip|developmental dysplasia of the hip]] (DDH). This is a test for posterior dislocation of the hip. Using the examiner's thumb, abduct the infant's leg, while using the examiner's index finger to place anterior pressure on the greater trochanter. A positive sign is a distinctive 'clunk' which can be heard and felt as the femoral head relocates anteriorly into the acetabulum, usually becomes negative after 2 months of age.  This test is combined with the [[B#Barlow test|Barlow test]] (maneuver).  
(Ortolani maneuver) A clinical term to describe a physical examination of the newborn for [[D#developmental dysplasia of the hip|developmental dysplasia of the hip]] (DDH). This is a test for posterior dislocation of the hip. Using the examiner's thumb, abduct the infant's leg, while using the examiner's index finger to place anterior pressure on the greater trochanter. A positive sign is a distinctive 'clunk' which can be heard and felt as the femoral head relocates anteriorly into the acetabulum, usually becomes negative after 2 months of age.  This test is combined with the [[B#Barlow test|Barlow test]] (maneuver).  


The test is named after Marino Ortolani, the test developer in 1976.
The test is named after Marino Ortolani, the test developer in 1976.
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===Abduction Splints===
===Abduction Splints===


There is variable evidence for the use of abduction splinting during onset of walking in children on the maturation of mild dysplastic hips.<ref name="PMID15958160" />
There is variable evidence for the use of abduction splinting during onset of walking in children on the maturation of mild dysplastic hips.{{#pmid:15958160|PMID15958160}}




:'''Links:''' [http://www.ncbi.nlm.nih.gov/pubmed/16510673 Screening for developmental dysplasia of the hip: recommendation statement. PMID16510673]
:'''Links:''' [[Developmental Hip Dysplasia]] Screening for developmental dysplasia of the hip: recommendation statement.{{#pmid:16510673|PMID16510673}}


==Developing Limb Regions==
==Developing Limb Regions==
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===Autopod===
===Autopod===


Limb development term describing the distal region the limb, the musculoskeletal component of the upper limb (forelimb) is the hands, and for the lower limb (hindlimb) is the foot.
Limb development term describing the distal region the limb, the musculoskeletal component of the upper limb (forelimb) is the hand, and for the lower limb (hindlimb) is the foot.


== Limb Abnormality Classification ==
== Limb Abnormality Classification ==
There have been a number of different classifications applied to limb abnormalities (Classic Classification, Frantz Classification, International Society for Prosthetics and Orthotics (ISPO) Classification System).  
There have been a number of different classifications applied to limb abnormalities (Classic Classification, Frantz Classification, International Society for Prosthetics and Orthotics (ISPO) Classification System).  


The current preferred classification system is the ISPO Classification,<ref><pubmed>1923724</pubmed></ref> which divides all limb deformities into either '''transverse''' (no distal remaining portions) or '''longitudinal''' (has distal portions).  
The current preferred classification system is the ISPO Classification,{{#pmid:1923724|PMID1923724}} which divides all limb deformities into either '''transverse''' (no distal remaining portions) or '''longitudinal''' (has distal portions).  


The original classical classification of limb deficiencies was:  
The original classical classification of limb deficiencies was:  
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== Hand Abnormality Classification ==
== Hand Abnormality Classification ==
There is now a international classification for congenital hand anomalies based on an extension of an earlier classification system.<ref><pubmed>12416642</pubmed></ref> Some of these abnormalities can be initially detected prenatally by ultrasound and may be associated with other syndromes or karyotype anomalies.  
There is now a international classification for congenital hand anomalies based on an extension of an earlier classification system.{{#pmid:12416642|PMID12416642}} Some of these abnormalities can be initially detected prenatally by ultrasound and may be associated with other syndromes or karyotype anomalies.  


===Groups===
===Groups===
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Syndactyly occuring in cattle is known as "mulefoot" an autosomal recessive trait and has been associated with mutations in the low density lipoprotein receptor-related protein 4 gene (LRP4). When shortening of the syndactyal digits also occurs it is then described as brachysyndactyly (Greek, ''brachys'' = short, ''syn'' = together, ''dactyly'' = digit). (More? [[#Brachydactyly|Brachydactyly]]).
Syndactyly occuring in cattle is known as "mulefoot" an autosomal recessive trait and has been associated with mutations in the low density lipoprotein receptor-related protein 4 gene (LRP4). When shortening of the syndactyal digits also occurs it is then described as brachysyndactyly (Greek, ''brachys'' = short, ''syn'' = together, ''dactyly'' = digit). (More? [[#Brachydactyly|Brachydactyly]]).


See also an article on molecular control of skeletal size with digit separation.<ref><pubmed>17360777</pubmed></ref>
See also an article on molecular control of skeletal size with digit separation.{{#pmid:17360777|PMID17360777}}


'''Links:''' OMIM - [http://www.ncbi.nlm.nih.gov/omim/185900 Syndactyly I] | [http://www.ncbi.nlm.nih.gov/omim/186000 Syndactyly II] | [http://www.ncbi.nlm.nih.gov/omim/186100 Syndactyly III] | [http://www.ncbi.nlm.nih.gov/omim/186200 Syndactyly IV] | [http://www.ncbi.nlm.nih.gov/omim/186300 Syndactyly V]
'''Links:''' OMIM - [http://www.ncbi.nlm.nih.gov/omim/185900 Syndactyly I] | [http://www.ncbi.nlm.nih.gov/omim/186000 Syndactyly II] | [http://www.ncbi.nlm.nih.gov/omim/186100 Syndactyly III] | [http://www.ncbi.nlm.nih.gov/omim/186200 Syndactyly IV] | [http://www.ncbi.nlm.nih.gov/omim/186300 Syndactyly V]
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== Polydactyly ==
== Polydactyly ==
[[Image:Polydactylia.jpg|thumb|Polydactylia (Image: CDC Imagebank)]]
[[File:Mall Meyer1921 fig93.jpg|thumb|alt=Right hand with six fingers|Right hand with six fingers]]
[[File:Polydactylia.jpg|t300px|left|Polydactylia (Image: CDC Imagebank)]]
 


Presence of additional toes or fingers (Greek, ''poly'' = many, ''dactyly'' = digit) also called polydactylia or polydactylism. The condition is often treated surgically in the infant. Polydactyly can also be associated with a number of different syndromes including Greig cephalopolysyndactyly syndrome (GCPS).
Presence of additional toes or fingers (Greek, ''poly'' = many, ''dactyly'' = digit) also called polydactylia or polydactylism. The condition is often treated surgically in the infant. Polydactyly can also be associated with a number of different syndromes including Greig cephalopolysyndactyly syndrome (GCPS).
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== Polysyndactyly ==
== Polysyndactyly ==
Developmental abnormality where there is a combination of additional digits (polydactyly) that are fused together (syndactyly) and is known as polysyndactyly.  See also article on treatment of congenital upper extremity problems.<ref><pubmed>17415231</pubmed></ref>
Developmental abnormality where there is a combination of additional digits (polydactyly) that are fused together (syndactyly) and is known as polysyndactyly.  See also article on treatment of congenital upper extremity problems.{{#pmid:17415231|PMID17415231}}


'''Search PubMed Now:''' [http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=search&term=Polysyndactyly Polysyndactyly]
'''Search PubMed Now:''' [http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=search&term=Polysyndactyly Polysyndactyly]
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Middle phalanges of both hands and feet are very short (Greek, ''brachys'' = short, ''dactyly'' = digit) in length or absent. Condition can also be associated with endocrine abnormality, pseudohypoparathyroidism (end-organ unresponsiveness to parathyroid hormone) leading to short stature, round facies, brachydactyly, and short fourth or fifth metacarpals.  
Middle phalanges of both hands and feet are very short (Greek, ''brachys'' = short, ''dactyly'' = digit) in length or absent. Condition can also be associated with endocrine abnormality, pseudohypoparathyroidism (end-organ unresponsiveness to parathyroid hormone) leading to short stature, round facies, brachydactyly, and short fourth or fifth metacarpals.  


A chromosomal translocation (t(4;6)(q12;p23) has also been shown to disrupt a membrane-associated O-acetyl transferase gene (MBOAT1) in a patient with a novel brachydactyly-syndactyly syndrome.<ref><pubmed>17440500</pubmed></ref> "One of the genes on chromosome 6, the membrane-associated O-acetyl transferase gene 1 (MBOAT1), was disrupted by the breakpoint. ...Identification of the transferred acyl group and the target may reveal the signaling pathways altered in this novel brachydactyly-syndactyly syndrome."
A chromosomal translocation (t(4;6)(q12;p23) has also been shown to disrupt a membrane-associated O-acetyl transferase gene (MBOAT1) in a patient with a novel brachydactyly-syndactyly syndrome.{{#pmid:17440500|PMID17440500}} "One of the genes on chromosome 6, the membrane-associated O-acetyl transferase gene 1 (MBOAT1), was disrupted by the breakpoint. ...Identification of the transferred acyl group and the target may reveal the signaling pathways altered in this novel brachydactyly-syndactyly syndrome."


'''Search PubMed Now:''' [http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=search&term=Brachydactyly Brachydactyly]
'''Search PubMed Now:''' [http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=search&term=Brachydactyly Brachydactyly]


== Symbrachydactyly ==
== Symbrachydactyly ==
Symbrachydactyly describes a combination of syndactyly accompanied by brachydactyly. See clinical article on surgical reconstruction in symbrachydactyly using the reverse radial forearm flap.<ref><pubmed>17275589</pubmed></ref>
Symbrachydactyly describes a combination of syndactyly accompanied by brachydactyly. See clinical article on surgical reconstruction in symbrachydactyly using the reverse radial forearm flap.{{#pmid:17275589|PMID17275589}}


'''Search PubMed Now:''' [http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=search&term=Symbrachydactyly Symbrachydactyly]
'''Search PubMed Now:''' [http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=search&term=Symbrachydactyly Symbrachydactyly]
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== Ectrodactyly ==
== Ectrodactyly ==
[[File:Clefthand-apical-defect.jpg|thumb|Cleft hand apical defect]]
[[File:Clefthand-apical-defect.jpg|thumb|Cleft hand apical defect]]
[[File:ectrodactyly.jpg|thumb|Ectrodactyly]]
 
Ectrodactyly or split hand/foot malformation (SHFM) or cleft hand, central ray deficiency (previously called "lobster-claw malformation"). Abnormality is a deep median cleft of either the hand and/or foot due to the embryonic absence of the central rays.  
Ectrodactyly or split hand/foot malformation (SHFM) or cleft hand, central ray deficiency (previously called "lobster-claw malformation"). Abnormality is a deep median cleft of either the hand and/or foot due to the embryonic absence of the central rays.  


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During limb development at the time of had or foot formation, the median apical ectodermal ridge (AER) fails to be maintained leading to an absence of its developmental regional signaling. Can have isolated vascular supply related cases and occur as part of a syndrome.  
During limb development at the time of had or foot formation, the median apical ectodermal ridge (AER) fails to be maintained leading to an absence of its developmental regional signaling. Can have isolated vascular supply related cases and occur as part of a syndrome.  
{|
|+ Ectrodactyly
| [[File:ectrodactyly.jpg|300px]]
| [[File:Ectrodactyly 01.jpg|300px]]
|}




'''Search PubMed Now:''' [http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=search&term=Ectrodactyly Ectrodactyly] | [http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=search&term=Split%20hand/foot%20malformation Split hand/foot malformation] |
'''Search PubMed Now:''' [http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=search&term=Ectrodactyly Ectrodactyly] | [http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=search&term=Split%20hand/foot%20malformation Split hand/foot malformation] |


== Triphalangeal Thumb (TPT) ==
[[Image:triphalangeal-thumb.jpg|thumb|Triphalangeal Thumb (Image modified from: Indian Pediatrics)]]
Developmental abnormality with three phalanges instead of two, forming a long, finger-like thumb.


The isolated triphalangeal thumb anomaly has also been mapped to chromosome region 7q36 and has been identified as caused by point mutations in the ZPA regulatory sequence (ZRS) which is a long-range cis-regulator for the SHH gene.<ref><pubmed>18417549</pubmed></ref>
== Triphalangeal Thumb==
{|
| The developmental abnormality {{triphalangeal thumb}} (TPT) has three phalanges instead of two, forming a long, finger-like thumb.
 
The isolated triphalangeal thumb anomaly has also been mapped to chromosome region {{Chr7}}q36 and has been identified as caused by point mutations in the ZPA regulatory sequence (ZRS) which is a long-range cis-regulator for the {{SHH}} gene.{{#pmid:18417549|PMID18417549}}{{#pmid:29543231|PMID29543231}} See also the recent reviews.{{#pmid:30318985|PMID30318985}}{{#pmid:330223699|PMID30223699}}
 


'''Search PubMed Now:''' [http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=search&term=Triphalangeal%20Thumb Triphalangeal Thumb]  
'''Search PubMed Now:''' [http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=search&term=Triphalangeal%20Thumb Triphalangeal Thumb]  


'''Links:''' [http://www.ncbi.nlm.nih.gov/entrez/dispomim.cgi?id=607343 OMIM - Sall4] | [http://www.ncbi.nlm.nih.gov/entrez/dispomim.cgi?id=601620 OMIM - Tbx5] | [http://www.indianpediatrics.net/dec2005/dec-1246-1247.HTM Indian Pediatrics - Indian Pediatrics 2005;42:1246-1247]
'''Links:''' [http://www.ncbi.nlm.nih.gov/entrez/dispomim.cgi?id=607343 OMIM - Sall4] | [http://www.ncbi.nlm.nih.gov/entrez/dispomim.cgi?id=601620 OMIM - Tbx5] | [http://www.indianpediatrics.net/dec2005/dec-1246-1247.HTM Indian Pediatrics - Indian Pediatrics 2005;42:1246-1247]
 
| [[File:triphalangeal-thumb.jpg|300px|alt=Triphalangeal Thumb|Triphalangeal Thumb (modified from Indian Pediatrics)]]
|}
== Talipes Equinovarus ==
== Talipes Equinovarus ==
[[File:Talipes equinovarus 01.jpg|thumb|Talipes equinovarus]]  
[[File:Fetal limb abnormalities X-ray-02.jpg|thumb|Talipes equinovarus (x-ray){{#pmid:24312362|PMID24312362}}]]
[[File:Talipes equinovarus 01.jpg|left]]  
(Latin, ''talipes'' = ankle bone, pes = foot, equinus = horse) Abnormality of the lower limb which begins in the embryonic period (first trimester of pregnancy) resulting in the foot is then turned inward and downward at birth, described as "club foot". Occurs in approximately 1 in 1,000 births, postnatally it affects how children walk on their toes with the foot pointed downward like a horse.
(Latin, ''talipes'' = ankle bone, pes = foot, equinus = horse) Abnormality of the lower limb which begins in the embryonic period (first trimester of pregnancy) resulting in the foot is then turned inward and downward at birth, described as "club foot". Occurs in approximately 1 in 1,000 births, postnatally it affects how children walk on their toes with the foot pointed downward like a horse.


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'''Search PubMed Now:''' [http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=search&term=Amniotic%20band%20syndrome Amniotic band syndrome] | [http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=search&term=amniotic%20bands amniotic bands] |  
'''Search PubMed Now:''' [http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=search&term=Amniotic%20band%20syndrome Amniotic band syndrome] | [http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=search&term=amniotic%20bands amniotic bands] |  


==Sirenomelia==
[[File:Sirenomelia 01.jpg|thumb|alt=Sirenomelia infant|Sirenomelia infant{{#pmid:24027712|PMID24027712}}]]
Sirenomelia (mermaid syndrome) is named after the mythical Greek sirens. A rare developmental abnormality (incidence of 0.8-1 case /100000 births), male to female ratio 3:1. While demonstrating limb developmental abnormalities, including a single fused lower limb, there are also associated multiple urogenital, anorectal and vascular malformations. The condition has also been associated with maternal diabetes.
Classified into type I to type VII according mainly to the presence of skeletal elements in the thigh and leg.{{#pmid:3588246|PMID3588246}} Two existing mouse models;{{#pmid:21504909|PMID21504909}} 1. lacking Cyp26a1, an enzyme that degrades retinoic acid (RA), 2. reduced bone morphogenetic protein (Bmp) signaling in the caudal embryonic region.
A recent mouse model has used a  bmp7;shh mutant model to look at signaling processes involved with this developmental abnormality.{{#pmid:23028704|PMID23028704}}
:'''Links:''' [[:File:Sirenomelia 01.jpg|Image - Sirenomelia infant]] | [[:File:Sirenomelia 02.jpg|Image - Sirenomelia x-ray]] |  [[Developmental Signals - Retinoic acid]] | [[Musculoskeletal_System_-_Limb_Abnormalities|Limb Abnormalities]] | [[Abnormal_Development_-_Maternal_Diabetes|Maternal Diabetes]]
== Limb Reduction ==
== Limb Reduction ==


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===Environment===
===Environment===


Thalidomide was the most celebrated limb reducing insult (teratogen) in humans which also produced a range of other deformities depending on developmental time and concentration of the drug exposure.  
[[Abnormal Development - Thalidomide|Thalidomide]] was the most well known example limb reducing insult (teratogen) in humans, which also produced a range of other deformities depending on developmental time and concentration of the drug exposure.  
 
<gallery caption="Thalidomide effects>
File:Thalidomide abnormalities 01.jpg|male limb abnormalities
File:Thalidomide abnormalities 02.jpg|female limb abnormalities
</gallery>


Many additional substances (teratogens) have been found capable of producing limb reduction defects in experimental animals but few have been related to humans.  
Many additional substances (teratogens) have been found capable of producing limb reduction defects in experimental animals but few have been related to humans.  
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Limb reduction defects may be apical (congenital amputation) or pre- or post-axial (absence of radius and lateral digits; ulnar and medial digits).
Limb reduction defects may be apical (congenital amputation) or pre- or post-axial (absence of radius and lateral digits; ulnar and medial digits).


'''Questions:'''
'''Links:''' [[Abnormal Development - Thalidomide]]
 
What area is missing in the reduced limb shown above?
 
What will be the relative growth rates of the right and left humeri in this child?
 
'''Search PubMed Now:''' [http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=search&term=Congenital%20Limb%20Reduction Congenital Limb Reduction] | [http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=search&term=Thalidomide Thalidomide]
 
'''Links:''' [[Abnormal Development - Thalidomide]] | [http://www.thalidomide.org/default_eng.asp? The Swedish Thalidomide Society]


'''Search PubMed Now:''' [http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=search&term=Congenital%20Limb%20Reduction Congenital Limb Reduction]
== Nail Abnormalities ==
== Nail Abnormalities ==
Covered in developmental notes on [skin2.htm Integumentary Development Abnormalities], [skin12.htm Nail Development] and [skin.htm Integumentary Development].  
Covered in developmental notes on Integumentary Development Abnormalities, [[Integumentary System - Nail Development|Nail Development]].  


Congenital hyponychia  
Congenital hyponychia  
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'''Search PubMed Now:''' [http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=search&term=Congenital%20hyponychia Congenital hyponychia] | [http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=search&term=Anonychia Anonychia ]
'''Search PubMed Now:''' [http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=search&term=Congenital%20hyponychia Congenital hyponychia] | [http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=search&term=Anonychia Anonychia ]


:'''Links:''' [[Integumentary System - Nail Development|Nail Development]] | [[Integumentary_System_-_Abnormalities|Integumentary Abnormalities]]
== References ==
== References ==
<references/>
<references/>
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===Reviews===
===Reviews===
<pubmed>22379552</pubmed>| [http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3288491 PMC3288491]
{{#pmid:22379552}}


<pubmed>17661738</pubmed>
{{#pmid:17661738}}


===Articles===
===Articles===
<pubmed></pubmed>
{{#pmid:17440500}}
<pubmed></pubmed>
 
<pubmed>17440500</pubmed>
{{#pmid:17275589}}
<pubmed>17275589</pubmed>
 
<pubmed>17300775</pubmed>
{{#pmid:17300775}}
<pubmed>16676441</pubmed>
 
<pubmed>1923724</pubmed>
{{#pmid:16676441}}
<pubmed>3618097</pubmed>
 
<pubmed>8172251</pubmed>
{{#pmid:1923724}}
 
{{#pmid:3618097}}
 
{{#pmid:8172251}}


===Search PubMed===
===Search PubMed===
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Polydactylia.jpg|Polydactylia
Polydactylia.jpg|Polydactylia
Syndactyly.jpg|Syndactyly
Syndactyly.jpg|Syndactyly
File:Left_hand_reduction_defect_01.jpg|Left hand reduction defect
File:Left_hand_reduction_defect_02.jpg|Left hand reduction defect x-ray
File:Left foot polydactyly 01.jpg|Left foot polydactyly
File:Left foot polydactyly 02.jpg|Left foot polydactyly x-ray
File:Fetal limb abnormalities X-ray-01.jpg|bowing of the radius and ulna, bowing of the digits, bowing and hypoplasia of the femur, tibia and fibula.
File:Fetal limb abnormalities X-ray-02.jpg|bowing of the digits, bowing and hypoplasia of the femur, tibia and fibula, and talipes equinovarus.
File:Fetal limb abnormalities X-ray-03.jpg|normal x-ray
File:Rabbitmalformation3.jpg|Brachydactylia malformation of rabbit limb
File:Rabbitmalformation3.jpg|Brachydactylia malformation of rabbit limb
</gallery>
</gallery>
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{{Template:Glossary}}
{{Glossary}}
 
 


{{Template:Footer}}
{{Footer}}


[[Category:System Development]] [[Category:Limb]] [[Category:Abnormal Development]]
[[Category:System Development]] [[Category:Limb]] [[Category:Abnormal Development]]

Revision as of 11:06, 1 November 2018

Embryology - 28 Mar 2024    Facebook link Pinterest link Twitter link  Expand to Translate  
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Stage20-23 limbs b.jpg

Introduction

Adult appendicular skeleton
Adult appendicular skeleton

Musculoskeletal and limb abnormalities are one of the largest groups of congenital abnormalities. The upper and lower limbs have a large number of different genetic and environment derived abnormalities, some of which can be surgically repaired, while others may indicate other syndromes or karyotype anomalies (trisomy etc) by association. Congenital limb agenesis and deficiencies prevalence is about 7.9/10,000 live births.


Hand and foot abnormalities are often described as different forms of "dactyly" from the Greek (daktulos) for finger or digit.


A key historic area of limb abnormalities were those associated with limb reduction (and other defects) with the "morning sickness" prescription drug Thalidomide and its significant teratogenic effects (More? Thalidomide).

A 1994 review of data from Hungary (1975-1984)[1] showed in this population an overall 1 in 1,816 prevalence of limb deficiency at birth.


Musculoskeletal Links: Introduction | mesoderm | somitogenesis | limb | cartilage | bone | bone timeline | bone marrow | shoulder | pelvis | axial skeleton | skull | joint | skeletal muscle | muscle timeline | tendon | diaphragm | Lecture - Musculoskeletal | Lecture Movie | musculoskeletal abnormalities | limb abnormalities | developmental hip dysplasia | cartilage histology | bone histology | Skeletal Muscle Histology | Category:Musculoskeletal
Historic Embryology - Musculoskeletal  
1853 Bone | 1885 Sphenoid | 1902 - Pubo-femoral Region | Spinal Column and Back | Body Segmentation | Cranium | Body Wall, Ribs, and Sternum | Limbs | 1901 - Limbs | 1902 - Arm Development | 1906 Human Embryo Ossification | 1906 Lower limb Nerves and Muscle | 1907 - Muscular System | Skeleton and Limbs | 1908 Vertebra | 1908 Cervical Vertebra | 1909 Mandible | 1910 - Skeleton and Connective Tissues | Muscular System | Coelom and Diaphragm | 1913 Clavicle | 1920 Clavicle | 1921 - External body form | Connective tissues and skeletal | Muscular | Diaphragm | 1929 Rat Somite | 1932 Pelvis | 1940 Synovial Joints | 1943 Human Embryonic, Fetal and Circumnatal Skeleton | 1947 Joints | 1949 Cartilage and Bone | 1957 Chondrification Hands and Feet | 1968 Knee

Some Recent Findings

French regions - Ain, Brittany and Loire-Atlantique
  • Review of triphalangeal thumb[2] "Despite being a rare congenital limb anomaly, triphalangeal thumb is a subject of research in various scientific fields, providing new insights in clinical research and evolutionary biology. The findings of triphalangeal thumb can be predictive for other congenital anomalies as part of an underlying syndrome. Furthermore, triphalangeal thumb is still being used as a model in molecular genetics to study gene regulation by long-range regulatory elements. We present a review that summarizes a number of scientifically relevant topics that involve the triphalangeal thumb phenotype. Future initiatives involving multidisciplinary teams collaborating in the field of triphalangeal thumb research can lead to a better understanding of the pathogenesis and molecular mechanisms of this condition as well as other congenital upper limb anomalies." See also PubmedParser error: The PubmedParser extension received invalid XML data. ()
  • Prenatal exposure to environmental factors and congenital limb defects[3] "Limb congenital defects afflict approximately 0.6:1000 live births. In addition to genetic factors, prenatal exposure to drugs and environmental toxicants, represents a major contributing factor to limb defects. Examples of well-recognized limb teratogenic agents include thalidomide, warfarin, valproic acid, misoprostol, and phenytoin. While the mechanism by which these agents cause dymorphogenesis is increasingly clear, prediction of the limb teratogenicity of many thousands of as yet uncharacterized environmental factors (pollutants) remains inexact."
  • Role of Genetic Factors in the Pathogenesis of Radial Deficiencies in Humans[4] "Radial deficiencies (RDs), defined as under/abnormal development or absence of any of the structures of the forearm, radial carpal bones and thumb, occur with a live birth incidence ranging from 1 out of 30,000 to 1 out 6,000 newborns and represent about one third/one fourth of all the congenital upper limb anomalies. About half of radial disorders have a mendelian cause and pattern of inheritance, whereas the remaining half appears sporadic with no known gene involved. In sporadic forms certain anomalies, such as thumb or radial hypoplasia, may occur either alone or in association with systemic conditions, like vertebral abnormalities or renal defects. All the cases with a mendelian inheritance are syndromic forms, which include cardiac defects (in Holt-Oram syndrome), bone marrow failure (in Fanconi anemia), platelet deficiency (in thrombocytopenia-absent-radius syndrome), ocular motility impairment (in Okihiro syndrome)."
More recent papers  
Mark Hill.jpg
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  • The displayed list of references do not reflect any editorial selection of material based on content or relevance.
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References listed on the rest of the content page and the associated discussion page (listed under the publication year sub-headings) do include some editorial selection based upon both relevance and availability.

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Search term: Abnormal Limb Development

<pubmed limit=5>Abnormal Limb Development</pubmed>

Older papers  
These papers originally appeared in the Some Recent Findings table, but as that list grew in length have now been shuffled down to this collapsible table.

See also the Discussion Page for other references listed by year and References on this current page.

  • Sirenomelia phenotype in bmp7;shh compound mutants: a novel experimental model for studies of caudal body malformations[5] "Sirenomelia is a severe congenital malformation of the lower body characterized by the fusion of the legs into a single lower limb. This striking external phenotype consistently associates severe visceral abnormalities, most commonly of the kidneys, intestine, and genitalia that generally make the condition lethal. Although the causes of sirenomelia remain unknown, clinical studies have yielded two major hypotheses: i) a primary defect in the generation of caudal mesoderm, ii) a primary vascular defect that leaves the caudal part of the embryo hypoperfused. ...We show that the signaling defect predominantly impacts the morphogenesis of the hindgut and the development of the caudal end of the dorsal aortas. The deficient formation of ventral midline structures, including the interlimb mesoderm caudal to the umbilicus, leads to the approximation and merging of the hindlimb fields."
  • Triphalangeal thumb-polysyndactyly syndrome and syndactyly type IV are caused by genomic duplications[6] "Both Triphalangeal thumb-polysyndactyly syndrome (TPTPS) and syndactyly type IV (SD4) are due to duplications involving ZPA regulatory sequence (ZRS), the limb-specific Sonic hedgehog (SHH) enhancer. Point mutations in the ZRS and duplications encompassing the ZRS cause distinctive limb phenotypes."
  • A t(4;6)(q12;p23) translocation disrupts a membrane-associated O-acetyl transferase gene (MBOAT1) in a patient with a novel brachydactyly-syndactyly syndrome[7] "One of the genes on chromosome 6, the membrane-associated O-acetyl transferase gene 1 (MBOAT1), was disrupted by the breakpoint. ...Identification of the transferred acyl group and the target may reveal the signaling pathways altered in this novel brachydactyly-syndactyly syndrome."
  • Characterization of a novel ectodermal signaling center regulating Tbx2 and Shh in the vertebrate limb[8] "The data presented here identify the non-AER border of dorsal-ventral ectoderm as a new signaling center in limb development that localizes the ZPA to the limb margin. This finding explains the tight restriction of Shh expression to the posterior margin throughout limb outgrowth as well as the tight restriction of Shh expression to the anterior margin in many mutants exhibiting preaxial polydactyly."

Textbooks

  • The Developing Human: Clinically Oriented Embryology (8th Edition) by Keith L. Moore and T.V.N Persaud - Moore & Persaud Chapter 15 the skeletal system
  • Larsen’s Human Embryology by GC. Schoenwolf, SB. Bleyl, PR. Brauer and PH. Francis-West - Chapter 11 Limb Dev (bone not well covered in this textbook)
  • Before we Are Born (5th ed.) Moore and Persaud Chapter 16,17: p379-397, 399-405
  • Essentials of Human Embryology Larson Chapter 11 p207-228

Developmental Dysplasia of the Hip

For more details see Developmental Hip Dysplasia.

ICD-10  
ICD-10 Q65 Congenital deformities of hip Excl.: clicking hip (R29.4)
Q65 Congenital deformities of hip

Excl.: clicking hip (R29.4)

  • Q65.0 Congenital dislocation of hip, unilateral
  • Q65.1 Congenital dislocation of hip, bilateral
  • Q65.2 Congenital dislocation of hip, unspecified
  • Q65.3 Congenital subluxation of hip, unilateral
  • Q65.4 Congenital subluxation of hip, bilateral
  • Q65.5 Congenital subluxation of hip, unspecified
  • Q65.6 Unstable hip Dislocatable hip Subluxatable hip
  • Q65.8 Other congenital deformities of hip Anteversion of femoral neck Congenital acetabular dysplasia Congenital coxa: valga vara
  • Q65.9 Congenital deformity of hip, unspecified
ICD-11 beta - LB74 
LB74 Structural developmental anomalies of pelvic girdle
Exclusions - Clicking hip (MG40)
  • LB74.1 Developmental dysplasia of hip
  • LB74.2 Congenital subluxation of hip
  • LB74.3 Unstable hip
  • LB74.4 Congenital coxa vara
  • LB74.5 Congenital coxa valga
  • LB74.6 Wide symphysis pubis
  • LB74.Y Other specified structural developmental anomalies of pelvic girdle
  • LB74.Z Structural developmental anomalies of pelvic girdle, unspecified
Congenital dislocation hip.jpg Renal agenesis 01.jpg
X-Ray Hip Dysplasia X-Ray Hip Dysplasia and renal agenesis[9]
Acetabular angle[10]


Also called Congenital Hip Dislocation.

  • Instability: 1:60 at birth; 1:240 at 1 wk: Dislocation untreated; 1:700
  • congenital instability of hip, later dislocates by muscle pulls or gravity
  • familial predisposition female predominance
  • Growth of femoral head, acetabulum and innominate bone are delayed until the femoral head fits firmly into the acetabulum


Barlow test

(Barlow maneuver) A clinical term to describe a physical examination of the newborn for developmental dysplasia of the hip (DDH). The examiner adducts the hip (bringing the thigh towards the midline) while applying light pressure on the knee, directing the force posteriorly. A positive sign is the hip being dislocatable, if the hip can be popped out of socket with this test. This test is then combined with the Ortolani test (maneuver).

The test is named after Thomas Barlow (1845 – 1945) a British royal physician.

Ortolani test

(Ortolani maneuver) A clinical term to describe a physical examination of the newborn for developmental dysplasia of the hip (DDH). This is a test for posterior dislocation of the hip. Using the examiner's thumb, abduct the infant's leg, while using the examiner's index finger to place anterior pressure on the greater trochanter. A positive sign is a distinctive 'clunk' which can be heard and felt as the femoral head relocates anteriorly into the acetabulum, usually becomes negative after 2 months of age. This test is combined with the Barlow test (maneuver).

The test is named after Marino Ortolani, the test developer in 1976.

Acetabular index

This clinical measurement is based upon radiograph analysis of the acetabular inclination before ossification of the triradiate cartilage. The index is defined as the angle between Hilgenreiner's line and a line from the inferior margin of the iliac bone through the acetabular bony rim.

Triradiate cartilage is the Y-shaped growth plate region within the hip that does not complete ossification postnatally in humans until 14 - 16 years of age.

X-ray landmarks

  • Hilgenreiner's line - a horizontal line drawn between the two triradiate cartilage centers of the hips, defines a horizontal plane and an approximation to flexion axis of the hips.
  • Perkin's line - a perpendicular line to the horizontal line drawn at the edge of the boney part of the acetabular socket.
  • Shenton's line - an oval that traces the lower pubis contour, that should smoothly continue on to trace the lower edge of the neck of the femur.

Abduction Splints

There is variable evidence for the use of abduction splinting during onset of walking in children on the maturation of mild dysplastic hips.[10]


Links: Developmental Hip Dysplasia Screening for developmental dysplasia of the hip: recommendation statement.[11]

Developing Limb Regions

Limb proximodistal developmental regions

The developing limb can be described along the proximodistal axis as having three main regions , with abnormalities along this axis characterised by the changes to these specific skeletal components.

Stylopod

Limb development term describing the proximal region the limb, the skeletal component of the upper limb (forelimb) is the humerus, and for the lower limb (hindlimb) is the femur.

Zeugopod

Limb development term describing the mid-section of the limb , the skeletal components of the upper limb (forelimb) are the radius and ulna, and for the lower limb (hindlimb) are the tibia and fibula.

Autopod

Limb development term describing the distal region the limb, the musculoskeletal component of the upper limb (forelimb) is the hand, and for the lower limb (hindlimb) is the foot.

Limb Abnormality Classification

There have been a number of different classifications applied to limb abnormalities (Classic Classification, Frantz Classification, International Society for Prosthetics and Orthotics (ISPO) Classification System).

The current preferred classification system is the ISPO Classification,[12] which divides all limb deformities into either transverse (no distal remaining portions) or longitudinal (has distal portions).

The original classical classification of limb deficiencies was:

  • Amelia - complete absence of a limb.
  • Meromelia - the partial absence of a limb.
  • Hemimelia - the absence of half a limb.
  • Phocomelia - a flipper-like appendage attached to the trunk. (limbs with a stylopod, a truncated or absent zeugopod, and a nearly intact autopod)
  • Acheiria a missing hand or foot.
  • Adactyly - the absence of metacarpal or metatarsal.
  • Aphalangia - an absent digit, finger or toe.

Hand Abnormality Classification

There is now a international classification for congenital hand anomalies based on an extension of an earlier classification system.[13] Some of these abnormalities can be initially detected prenatally by ultrasound and may be associated with other syndromes or karyotype anomalies.

Groups

I. Failure of formation; transverse (A), or longitudinal (B) (radial and ulnar deficiencies, symbrachydactyly)
II. Failure of differentiation
III. Polydactyly (513 anomalies, Madelung deformity, the Kirner deformity and congenital trigger fingers and trigger thumbs, Triphalangeal thumbs)
IV. Overgrowth
V. Undergrowth
VI. Amniotic band syndrome (amniotic bands)
VII. Generalized skeletal syndromes.
Failure of finger ray induction (cleft hand (IC), central polydactyly (III) and (bony) syndactyly (II)
Unclassifiable


Alignment abnormalities (clenched hand, camptodactyly, clinodactyly, hypokinesia, clubhand, phocomelia), thumb anomalies, abnormal size (macrodactyly, trident hand), abnormal echogenicity (abnormal calcifications), abnormal number (polydactyly, syndactyly, ectrodactyly), and constriction band sequence.

Syndactyly

Syndactyly

Fusion of fingers or toes (Greek, syn = together, dactyly = digit) which may be single or multiple and may affect: skin only, skin and soft tissues or skin, soft tissues and bone. The condition is unimportant in toes but disabling in fingers and requires operative separation and is frequently inherited as an autosomal dominant. The presence of this additional "webbing" reflects preservation of the developmental tissues that in normal development are removed by programmed cell death (apotosis).

Syndactyly occuring in cattle is known as "mulefoot" an autosomal recessive trait and has been associated with mutations in the low density lipoprotein receptor-related protein 4 gene (LRP4). When shortening of the syndactyal digits also occurs it is then described as brachysyndactyly (Greek, brachys = short, syn = together, dactyly = digit). (More? Brachydactyly).

See also an article on molecular control of skeletal size with digit separation.[14]

Links: OMIM - Syndactyly I | Syndactyly II | Syndactyly III | Syndactyly IV | Syndactyly V

Search PubMed Now: Syndactyly | Syndactylia |

Polydactyly

Right hand with six fingers
Right hand with six fingers
Polydactylia (Image: CDC Imagebank)


Presence of additional toes or fingers (Greek, poly = many, dactyly = digit) also called polydactylia or polydactylism. The condition is often treated surgically in the infant. Polydactyly can also be associated with a number of different syndromes including Greig cephalopolysyndactyly syndrome (GCPS).

There are also several forms of polydactyly including: preaxial polydactyly type-IV (PPD-IV) and postaxial polydactyly.

Preaxial polydactyly (PPD) has been shown as a defect in Sonic Hedgehog (Shh) expression. SHH is normally expressed specifically in the zone of polarizing activity (ZPA) located posteriorly in the limb bud and is expressed in an additional ectopic site (at the anterior margin) in a mouse model of this disorder.

This expression appears to be due to point mutations in the limb-specific regulatory element of the SHH gene.

Six digit cat

The author Ernest Hemmingway in the 1930's had a six-toed cat (Snowball) showing a form of polydactyly and cats with a similar condition today (image) are now called "Hemmingway cats".

Search PubMed Now: Polydactyly | Polydactylia |

Polysyndactyly

Developmental abnormality where there is a combination of additional digits (polydactyly) that are fused together (syndactyly) and is known as polysyndactyly. See also article on treatment of congenital upper extremity problems.[15]

Search PubMed Now: Polysyndactyly

Brachydactyly

Middle phalanges of both hands and feet are very short (Greek, brachys = short, dactyly = digit) in length or absent. Condition can also be associated with endocrine abnormality, pseudohypoparathyroidism (end-organ unresponsiveness to parathyroid hormone) leading to short stature, round facies, brachydactyly, and short fourth or fifth metacarpals.

A chromosomal translocation (t(4;6)(q12;p23) has also been shown to disrupt a membrane-associated O-acetyl transferase gene (MBOAT1) in a patient with a novel brachydactyly-syndactyly syndrome.[7] "One of the genes on chromosome 6, the membrane-associated O-acetyl transferase gene 1 (MBOAT1), was disrupted by the breakpoint. ...Identification of the transferred acyl group and the target may reveal the signaling pathways altered in this novel brachydactyly-syndactyly syndrome."

Search PubMed Now: Brachydactyly

Symbrachydactyly

Symbrachydactyly describes a combination of syndactyly accompanied by brachydactyly. See clinical article on surgical reconstruction in symbrachydactyly using the reverse radial forearm flap.[16]

Search PubMed Now: Symbrachydactyly

Ectrodactyly

Cleft hand apical defect

Ectrodactyly or split hand/foot malformation (SHFM) or cleft hand, central ray deficiency (previously called "lobster-claw malformation"). Abnormality is a deep median cleft of either the hand and/or foot due to the embryonic absence of the central rays.

Highly variable malformation (genetic heterogeneous, 5+ loci mapped) occuring in isolation or in association with other systematic anomalies including congenital heart defects.

During limb development at the time of had or foot formation, the median apical ectodermal ridge (AER) fails to be maintained leading to an absence of its developmental regional signaling. Can have isolated vascular supply related cases and occur as part of a syndrome.

Ectrodactyly
Ectrodactyly.jpg Ectrodactyly 01.jpg


Search PubMed Now: Ectrodactyly | Split hand/foot malformation |


Triphalangeal Thumb

The developmental abnormality triphalangeal thumb (TPT) has three phalanges instead of two, forming a long, finger-like thumb.

The isolated triphalangeal thumb anomaly has also been mapped to chromosome region 7q36 and has been identified as caused by point mutations in the ZPA regulatory sequence (ZRS) which is a long-range cis-regulator for the SHH gene.[6][17] See also the recent reviews.[2]PubmedParser error: The PubmedParser extension received invalid XML data. ()


Search PubMed Now: Triphalangeal Thumb

Links: OMIM - Sall4 | OMIM - Tbx5 | Indian Pediatrics - Indian Pediatrics 2005;42:1246-1247

Triphalangeal Thumb

Talipes Equinovarus

Talipes equinovarus (x-ray)[18]
Talipes equinovarus 01.jpg

(Latin, talipes = ankle bone, pes = foot, equinus = horse) Abnormality of the lower limb which begins in the embryonic period (first trimester of pregnancy) resulting in the foot is then turned inward and downward at birth, described as "club foot". Occurs in approximately 1 in 1,000 births, postnatally it affects how children walk on their toes with the foot pointed downward like a horse.

Can also occur in asociation with other syndromes. For example, camptomelic dysplasia, an extremely rare (2 per million live births) lethal congenital bony dysplasia which can be detected by ultrasound (25 weeks) visible as anterior bowing of long bones.

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Links: Medline Plus - Clubfoot | The Clubfoot Club |

Amniotic band syndrome (amniotic bands)

Amniotic constriction bands are relatively rare and is caused by damage to the amnion, producing fiber-like bands that trap periperal structures (arms, legs, fingers, or toes) reducing local blood supply leading to abnormal development.

Abnormalities range from a permanent band or indentation around the structure (arm, leg, finger, or toe), digital webbing, too all or part of the limb missing.

Search PubMed Now: Amniotic band syndrome | amniotic bands |

Sirenomelia

Sirenomelia infant
Sirenomelia infant[19]

Sirenomelia (mermaid syndrome) is named after the mythical Greek sirens. A rare developmental abnormality (incidence of 0.8-1 case /100000 births), male to female ratio 3:1. While demonstrating limb developmental abnormalities, including a single fused lower limb, there are also associated multiple urogenital, anorectal and vascular malformations. The condition has also been associated with maternal diabetes.

Classified into type I to type VII according mainly to the presence of skeletal elements in the thigh and leg.[20] Two existing mouse models;[21] 1. lacking Cyp26a1, an enzyme that degrades retinoic acid (RA), 2. reduced bone morphogenetic protein (Bmp) signaling in the caudal embryonic region.

A recent mouse model has used a bmp7;shh mutant model to look at signaling processes involved with this developmental abnormality.[5]


Links: Image - Sirenomelia infant | Image - Sirenomelia x-ray | Developmental Signals - Retinoic acid | Limb Abnormalities | Maternal Diabetes

Limb Reduction

Congenital Limb Reduction
X-ray of Limb Reduction

Genetic

There are many different genetic abnormalities and syndromes that have an associated limb reduction.

Trisomy 21 hand

Trisomy 21 - (Down Syndrome) features short and broad hands, clinodactyly (curving of the fifth finger, little finger) with a single flexion crease (20%), hyperextensible finger joints, space between the great toe (big) and the second toe is increased, and acquired hip dislocation (6%).

Diastrophic dysplasia - an autosomal recessive disorder, due to mutations in the DTD sulphate transporter gene (chromosome 5q32–q33). Leads to severe short-limbed dwarfism, progressive spinal and joint problems and can be detected by ultrasound (16 and 19 weeks of gestation).

Environment

Thalidomide was the most well known example limb reducing insult (teratogen) in humans, which also produced a range of other deformities depending on developmental time and concentration of the drug exposure.

Many additional substances (teratogens) have been found capable of producing limb reduction defects in experimental animals but few have been related to humans.

Limb reduction defects may also be either direct or indirect, for example with loss of blood supply to part of the limb or abnormal innervation at the spinal or cerebral level. There are a number of as yet undefined mechanisms involved.

Limb reduction defects may be apical (congenital amputation) or pre- or post-axial (absence of radius and lateral digits; ulnar and medial digits).

Links: Abnormal Development - Thalidomide

Search PubMed Now: Congenital Limb Reduction

Nail Abnormalities

Covered in developmental notes on Integumentary Development Abnormalities, Nail Development.

Congenital hyponychia

Anonychia

Nail-patella syndrome

Ectodermal dysplasias

Brachydactylies

Search PubMed Now: Congenital hyponychia | Anonychia


Links: Nail Development | Integumentary Abnormalities

References

  1. Evans JA, Vitez M & Czeizel A. (1994). Congenital abnormalities associated with limb deficiency defects: a population study based on cases from the Hungarian Congenital Malformation Registry (1975-1984). Am. J. Med. Genet. , 49, 52-66. PMID: 8172251 DOI.
  2. 2.0 2.1 Potuijt JWP, Galjaard RH, van der Spek PJ, van Nieuwenhoven CA, Ahituv N, Oberg KC & Hovius SER. (2018). A multidisciplinary review of triphalangeal thumb. J Hand Surg Eur Vol , , 1753193418803521. PMID: 30318985 DOI.
  3. Alexander PG, Clark KL & Tuan RS. (2016). Prenatal exposure to environmental factors and congenital limb defects. Birth Defects Res. C Embryo Today , 108, 243-273. PMID: 27768243 DOI.
  4. Elmakky A, Stanghellini I, Landi A & Percesepe A. (2015). Role of Genetic Factors in the Pathogenesis of Radial Deficiencies in Humans. Curr. Genomics , 16, 264-78. PMID: 26962299 DOI.
  5. 5.0 5.1 Garrido-Allepuz C, González-Lamuño D & Ros MA. (2012). Sirenomelia phenotype in bmp7;shh compound mutants: a novel experimental model for studies of caudal body malformations. PLoS ONE , 7, e44962. PMID: 23028704 DOI.
  6. 6.0 6.1 Sun M, Ma F, Zeng X, Liu Q, Zhao XL, Wu FX, Wu GP, Zhang ZF, Gu B, Zhao YF, Tian SH, Lin B, Kong XY, Zhang XL, Yang W, Lo WH & Zhang X. (2008). Triphalangeal thumb-polysyndactyly syndrome and syndactyly type IV are caused by genomic duplications involving the long range, limb-specific SHH enhancer. J. Med. Genet. , 45, 589-95. PMID: 18417549 DOI.
  7. 7.0 7.1 Dauwerse JG, de Vries BB, Wouters CH, Bakker E, Rappold G, Mortier GR, Breuning MH & Peters DJ. (2007). A t(4;6)(q12;p23) translocation disrupts a membrane-associated O-acetyl transferase gene (MBOAT1) in a patient with a novel brachydactyly-syndactyly syndrome. Eur. J. Hum. Genet. , 15, 743-51. PMID: 17440500 DOI.
  8. Nissim S, Allard P, Bandyopadhyay A, Harfe BD & Tabin CJ. (2007). Characterization of a novel ectodermal signaling center regulating Tbx2 and Shh in the vertebrate limb. Dev. Biol. , 304, 9-21. PMID: 17300775 DOI.
  9. Acién P, Galán F, Manchón I, Ruiz E, Acién M & Alcaraz LA. (2010). Hereditary renal adysplasia, pulmonary hypoplasia and Mayer-Rokitansky-Küster-Hauser (MRKH) syndrome: a case report. Orphanet J Rare Dis , 5, 6. PMID: 20388228 DOI.
  10. 10.0 10.1 Windhagen H, Thorey F, Kronewid H, Pressel T, Herold D & Stukenborg-Colsman C. (2005). The effect of functional splinting on mild dysplastic hips after walking onset. BMC Pediatr , 5, 17. PMID: 15958160 DOI.
  11. US Preventive Services Task Force. (2006). Screening for developmental dysplasia of the hip: recommendation statement. Pediatrics , 117, 898-902. PMID: 16510673 DOI.
  12. Day HJ. (1991). The ISO/ISPO classification of congenital limb deficiency. Prosthet Orthot Int , 15, 67-9. PMID: 1923724 DOI.
  13. De Smet L. (2002). Classification for congenital anomalies of the hand: the IFSSH classification and the JSSH modification. Genet. Couns. , 13, 331-8. PMID: 12416642
  14. Ota S, Zhou ZQ, Keene DR, Knoepfler P & Hurlin PJ. (2007). Activities of N-Myc in the developing limb link control of skeletal size with digit separation. Development , 134, 1583-92. PMID: 17360777 DOI.
  15. Netscher DT & Baumholtz MA. (2007). Treatment of congenital upper extremity problems. Plast. Reconstr. Surg. , 119, 101e-129e. PMID: 17415231 DOI.
  16. Gülgönen A & Güdemez E. (2007). Reconstruction of the first web space in symbrachydactyly using the reverse radial forearm flap. J Hand Surg Am , 32, 162-7. PMID: 17275589 DOI.
  17. Potuijt JWP, Baas M, Sukenik-Halevy R, Douben H, Nguyen P, Venter DJ, Gallagher R, Swagemakers SM, Hovius SER, van Nieuwenhoven CA, Galjaard RH, van der Spek PJ, Ahituv N & de Klein A. (2018). A point mutation in the pre-ZRS disrupts sonic hedgehog expression in the limb bud and results in triphalangeal thumb-polysyndactyly syndrome. Genet. Med. , , . PMID: 29543231 DOI.
  18. ten Broek CM, Bots J, Varela-Lasheras I, Bugiani M, Galis F & Van Dongen S. (2013). Amniotic fluid deficiency and congenital abnormalities both influence fluctuating asymmetry in developing limbs of human deceased fetuses. PLoS ONE , 8, e81824. PMID: 24312362 DOI.
  19. Kshirsagar VY, Ahmed M & Colaco SM. (2012). Sirenomelia apus: a rare deformity. J Clin Neonatol , 1, 146-8. PMID: 24027712 DOI.
  20. Stocker JT & Heifetz SA. (1987). Sirenomelia. A morphological study of 33 cases and review of the literature. Perspect Pediatr Pathol , 10, 7-50. PMID: 3588246
  21. Garrido-Allepuz C, Haro E, González-Lamuño D, Martínez-Frías ML, Bertocchini F & Ros MA. (2011). A clinical and experimental overview of sirenomelia: insight into the mechanisms of congenital limb malformations. Dis Model Mech , 4, 289-99. PMID: 21504909 DOI.


Reviews

Tonkin MA. (2012). Thumb duplication: concepts and techniques. Clin Orthop Surg , 4, 1-17. PMID: 22379552 DOI.

Hill RE. (2007). How to make a zone of polarizing activity: insights into limb development via the abnormality preaxial polydactyly. Dev. Growth Differ. , 49, 439-48. PMID: 17661738 DOI.

Articles

Dauwerse JG, de Vries BB, Wouters CH, Bakker E, Rappold G, Mortier GR, Breuning MH & Peters DJ. (2007). A t(4;6)(q12;p23) translocation disrupts a membrane-associated O-acetyl transferase gene (MBOAT1) in a patient with a novel brachydactyly-syndactyly syndrome. Eur. J. Hum. Genet. , 15, 743-51. PMID: 17440500 DOI.

Gülgönen A & Güdemez E. (2007). Reconstruction of the first web space in symbrachydactyly using the reverse radial forearm flap. J Hand Surg Am , 32, 162-7. PMID: 17275589 DOI.

Nissim S, Allard P, Bandyopadhyay A, Harfe BD & Tabin CJ. (2007). Characterization of a novel ectodermal signaling center regulating Tbx2 and Shh in the vertebrate limb. Dev. Biol. , 304, 9-21. PMID: 17300775 DOI.

Guven MA, Batukan C, Ceylaner S, Ceylaner G & Uzel M. (2006). A case of fetal anticonvulsant syndrome with severe bilateral upper limb defect. J. Matern. Fetal. Neonatal. Med. , 19, 115-7. PMID: 16676441

Day HJ. (1991). The ISO/ISPO classification of congenital limb deficiency. Prosthet Orthot Int , 15, 67-9. PMID: 1923724 DOI.

McKee PR & Bagnall KM. (1987). Skeletal relationships in the human embryonic foot based on three-dimensional reconstructions. Acta Anat (Basel) , 129, 34-42. PMID: 3618097

Evans JA, Vitez M & Czeizel A. (1994). Congenital abnormalities associated with limb deficiency defects: a population study based on cases from the Hungarian Congenital Malformation Registry (1975-1984). Am. J. Med. Genet. , 49, 52-66. PMID: 8172251 DOI.

Search PubMed

Search Pubmed: limb developmental abnormalities

Additional Images

Terms

  • preaxial - referring to the lateral (radial) aspect of the upper limb, and the medial (tibial) aspect of the lower limb.
  • postaxial - referring to the medial ( ulnar) aspect of the upper limb, and the lateral (fibular) aspect of the lower limb.


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Cite this page: Hill, M.A. (2024, March 28) Embryology Musculoskeletal System - Limb Abnormalities. Retrieved from https://embryology.med.unsw.edu.au/embryology/index.php/Musculoskeletal_System_-_Limb_Abnormalities

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© Dr Mark Hill 2024, UNSW Embryology ISBN: 978 0 7334 2609 4 - UNSW CRICOS Provider Code No. 00098G