Stiff facies, open mouth, high arched palate with
cleft. Craniostenosis and microcephaly. Swallowing difficulties and
generalized myopathic hypotonia. Respiratory insufficiency that generally
leads to death in early infancy.
Approximately 10 cases have been
reported. Inheritance seems to be autosomal recessive.
Dysmyelination characterized by excessive
myelin-dependent gliosis, myelin solubilization, and transient formation of
phospholipid-containing plaques on the brain's surface.
Clinical features and absence of extension of the thumb
during the Moro reflex.
Typical features are craniostenosis,
microcephaly, large occiput, mental retardation, seizures, external
ophthalmoplegia, myopathic stiff facies, low-set and large, malrotated ears,
open mouth, microgenia, abnormal temporomandibular joints (anomaly of the
processus condylaris and mandibulares), high arched palate with cleft, and
velopharyngeal insufficiency are common findings. Swallowing difficulties
(absent gag reflex) and generalized myopathic hypotonia are typical.
Laryngomalacia, recurrent pneumonias, and pectus excavatum have been
described in the majority of patients. The most characteristic sign is
flexion and adduction of the thumbs with arthrogryposis of elbows, wrists,
and knees. Respiratory insufficiency is mainly caused by the generalized
myopathic hypotonia and the main reason for the poor prognosis with death in
early infancy (only one patient has survived the first year of life). Muscle
biopsy reveals unspecific signs of congenital myopathy (i.e., wide variation
in the diameter of muscle fibers, normal distribution of type I and II
fibers, increased number of centrally located nuclei, increased interstitial
tissue, lack of signs of denervation).
Obtain a history of developmental
milestones, muscular hypotonia, recent chest infections, and swallowing
difficulties. Assess respiratory function and obtain chest radiograph.
Arterial blood gas analysis may be helpful under certain circumstances.
Postoperative mechanical ventilation is likely given the poor muscle
function and the associated respiratory problems (pneumonia,
Although difficult airway management
would be expected given the facial anomalies described, no tracheal
intubation problems have been reported in these children. Arthrogryposis may
make vascular access and positioning difficult. Respiratory insufficiency
likely will require intermittent positive pressure ventilation (IPPV) postoperatively.
No data are available; however,
avoiding depolarizing agents in patients with congenital myopathies is
MASA Syndrome: Syndrome characterized by acrocephaly,
brachycephaly, flat occiput, and maxillary hypoplasia. The mouth is small
and the upper lip is thin. Muscular hypertrophy of the legs and subluxation
of the hip.
Arthrogryposis: Spectrum of different syndromes characterized
by persistent multiple limb contractures. Often associated with pharyngeal,
cardiac, urinary, and gastric abnormalities. Often midline dysraphism
Christian Syndrome I (Christian-Andrews-Conneally-Muller
Syndrome): Adducted thumbs syndrome with craniosynostosis, arthrogryposis,
and cleft palate. Microcephaly, prominent occiput, hypertelorism,
antimongoloid palpebral fissures, ophthalmoplegia, abnormal ear placement,
and bifid uvula. Autosomal recessive.
Freeman-Sheldon Syndrome (FSS): Genetic malformative disorder
characterized by microstomia, flat midface with a small pinched mouth
mimicking whistling, clubfoot, contracted muscles of the joints of the
fingers, and hands malformations.
Congenital Clasped Thumbs: Extremely rare disorder that is ...