Proximal symphalangism

Alternate names

Strasburger-Hawkins-Eldridge syndrome; Strasburger-Hawkins-Eldridge-Hargrave-McKusick syndrome; Vessel’s syndrome; Hereditary absence of proximal interphalangeal joints; Proximal symphalangism; Cushing's symphalangism ; Symphalangism, proximal, 1A (subtype); Symphalangism, proximal, 1B (subtype)

Definition

Proximal symphalangism, which is also called Cushing's symphalangism, is a rare genetic condition characterized by the fusion of the proximal joints in the hands and feet.

Cause

It is caused by a mutation in the NOG gene or GDF5 gene.

Inheritance

Autosomal dominant pattern, a 50/50 chance.

This condition is inherited in an autosomal dominant pattern.

Signs and symptoms

• These individuals usually have straight fingers and are unable to make a fist.
• Other joints may also be affected, leading to stiff joints in the elbows, ankles and wrists.
• Hearing loss due to the fusion of the auditory ossicles (bones in the middle ear) is also a characteristic feature.

Clinical presentation

For most diseases, symptoms will vary from person to person. People with the same disease may not have all the symptoms listed.

80%-99% of people have these symptoms

• Camptodactyly of finger(Permanent flexion of the finger)
• Proximal symphalangism
• Proximal symphalangism of hands(Fused innermost hinge joints)
• Synostosis of carpal bones(Fusion of wrist bones)
• Tarsal synostosis(Fused ankle bones)

30%-79% of people have these symptoms

• Brachydactyly(Short fingers or toes)
• Carpal synostosis
• Conductive hearing impairment(Conductive deafness)
• Elbow ankylosis
• Elbow dislocation(Dislocations of the elbows)
• Metacarpophalangeal synostosis(Fused long bone of hand with innermost finger bone)
• Sensorineural hearing impairment
• Stapes ankylosis

5%-29% of people have these symptoms

• Aplasia/Hypoplasia of the middle phalanges of the hand(Absent/small middle finger bone of the hand)
• Aplasia/Hypoplasia of the middle phalanges of the toes(Absent/small middle bones of toe)
• Clinodactyly of the 5th finger(Permanent curving of the pinkie finger)
• Distal symphalangism of hands(Fused outermost bones of hand)
• Finger syndactyly
• Strabismus
• Cross-eyed

NIH genetic and rare disease info

• NIH info on Proximal symphalangism

Proximal symphalangism is a rare disease.

Resources

Frequently asked questions

‎