Adducted thumb syndrome recessive form, also known as Christian syndrome or Craniostenosis arthrogryposis cleft palate, is a rare disease affecting multiple systems which causes malformations of the palate, thumbs, and upper limbs.
The disease was documented in 1971 by Dr. Joe Christian and three associates after examining three Amish siblings.
This syndrome is associated with microcephaly, arthrogryposis, and cleft palate and various craniofacial, respiratory, neurological, and limb abnormalities, including bone and joint defects of the upper limbs, adducted thumbs, camptodactyly, and talipes equinovarus or calcaneovalgus. Patients with the disease are considered mentally retarded, and most die in childhood. Patients often suffer from respiratory difficulties, such as pneumonia, and from seizures due to dysmyelination in the white matter. It has been hypothesized that the Moro reflex (startle reflex in infants) may be a tool in detecting the congenital clapsed thumb early in infancy. The thumb will normally extend as a result of this reflex.