Multiple pterygium

Dr.V.Ravimohan

http://www.mrcogexam.net

What is pterygium?

– Pterygia are soft tissue webs across a joint or across the neck

When does it happen?

generalised association-Trisomies,Turner’s,Noonan’

specific syndrome-popliteal pterygium

antecubital pterygium syndrome

multiple pterygium syndrome

specific syndrome

popliteal pterygium-popliteal web + facial anomalies

antecubital pterygium syndrome-web extending across the cubital fossa + anomalies of the radial head + radio-ulnar joint

multiple pterygium syndrome webbing of variable degrees involving the neck, axilla, elbow, knee and digits associated with short stature and orofacial anomalies.

multiple pterygium syndromes

phenotypically and genetically heterogeneous (autosomal recessive,autosomal dominant or sporadic)

lethal and nonlethal (Escobar) types

nonlethal multiple pterygium syndrome(Escobar)

can be caused by mutation in the CHRNG gene, encoding the gamma subunit of the acetylcholine receptor (AChR).

Mutations in this gene can also cause the lethal variant of this phenotype

Escobar

• Webbing ofneck

antecubital fossae

popliteal fossae

with sternal deformity and male hypogonadism

may behave sometimes as a dominant, but there clearly appears to be a recessive type

Escobar

• multiple joint contractures with crouched stance and cleft palate

• Males had small penis and scrotum and cryptorchidism

• females had aplasia of the labia majora and small clitoris.

Skeletal anomalies

fusion of cervical vertebrae

scoliosis

flexion contraction of fingers

'rocker-bottom' feet with vertical talus

Clinical features

• intrauterine death• congenital respiratory distress• short stature• faciocranial dysmorphism• ptosis• low-set ears• Arachnodactyly• cryptorchism in males

Escobar

• first diagnostic sign is that of reduced fetal movement detected by ultrasound or reported by mothers.

• At birth, – variable joint contractures– multiple pterygia– facial dysmorphism with long face, high-

arched palate, small mouth, and retrognathism.

Escobar

• Respiratory distress is a frequent life-threatening complication.

• Later in life– patients frequently are affected by reduced

muscular mass but do not show myasthenic symptoms

– normal electromyelogram (EMG), except for unspecific indication of chronic myopathy.

Pathogenesis

mutations in the gamma, or fetal, subunit of the nicotinergic acetylcholine receptor

reduced fetal movements at sensitive times of development

CHRNG gene

• encodes the gamma subunit of the AChR

• expressed before the 33rd week of gestation in humans

• replaced by the epsilon subunit in the late fetal and perinatal period, thereby forming the adult AChR.

• AChRs have five subunits.

• Two α, one β, and one δ subunit are always present.

• By switching γ to subunits in late fetal development, fetal AChRs are gradually replaced by adult AChRs.

Other reasons for reduced fetal movements

Oligohydramnion

Drugs

metabolic conditions

neuromuscular disorders including myasthenia gravis

popliteal pterygium syndrome

Autosomal dominant with contractures limited to the knee

Repercussions that are only functional

popliteal pterygium syndrome

• least 3 of the following deformities.– Cleft lip & palate– Popliteal pterygium– Paramedian lower lip sinuses– Genital anomalies

– Dr.Sanjay Y.Parashar et al,.Spectrum of features in pterygium syndrome:Asian Journal of Surgery Vol 29:No 2 April 2006

MPS vs PPS

• MPS -primary pathlogy ptergium– Facial and limb anomalies may be secondary to

contracture

• PPS-all the anomalies appear to be part of multisystem involvement

Dr.Sanjay Y.Parashar et al,.Spectrum of features in pterygium syndrome:Asian Journal of Surgery Vol 29:No 2 April 2006

MPS vs PPSVictor Escobar et al.Mutiple Pterygium sundrome:Am J Dis Child –Vol 132,June 1978

MPS PPS

No Cleft lip/palate

No Lip pits

No sygnathia

No Ankyloblepharon

Absence of pterygia in neck/axillary region/antecubital fossa

Autosomal recessive Autosomal dominant

Cleft palate is present in 41% of cases Cleft lip(with or without cleft palate) present in nearly all cases

Frias' syndrome

Distinct form of the multiple pterygium syndrome with ptosis and skeletal anomalies.

Inheritance is autosomal dominant.

Jaime L. Frias, J. R. Holahan, A. L. Rosenbloom, A. H. Felman:

An autosomal dominant syndrome of multiple pterygium, ptosis, and skeletal anomalities. Fourth International Conference on Birth Defects. Vienna 1973. Excerpta Medica, 19.

ESCOBAR vs Frias

ESCOBAR Frias

Arthrogryposis with pterygia Arthrogryposis with pterygia

ptosis ptosis

Antimongoloid slant of palperal fissures

Antimongoloid slant of palperal fissures

Scoliosis Scoliosis

Always short stature Malsegmentation of spine

Management

• Multidisciplinary team• Paediatrician• Physiotherapist• Orthopaedic surgeon