trismus-pseudocamptodactyly syndrome (Hecht-Beals syndrome, Dutch-Kentucky syndrome)

Pathology

• distal arthrogryposis
• hand & jaw contractures are caused by shortened flexor muscle- tendon units

Genetics

• autosomal dominant
• variable expressivity but high penetrance
• associated with defects in MYH8

Clinical manifestations

• inability to open the mouth fully (trismus)
• pseudocamptodactyly in which wrist dorsiflexion, but not volar flexion, produces involuntary flexion contracture of distal & proximal interphalangeal joints
• similar lower-limb contractures also produce foot deformity

Complications

• trismus complicates dental care, feeding during infancy, & intubation for anesthesia
• pseudocamptodactyly impairs manual dexterity, with consequent occupational & social disability

Management

• many patients require surgical correction of contracture

More general terms

• genetic syndrome (multisystem disorder)

Database

• OMIM: https://mirror.omim.org/entry/158300