Correction of disorders of the distal radio-ulnar joint by artificial pseudarthrosis of the ulna.

Dysfunction of the distal radio-ulnar joint caused by traumatic, congenital and inflammatory onditions is usually treated by excision of the head of the ulna. This operation can induce ulnar carpal shift, with complications such as instability with poor grip, pain and clumsiness of the wrist, if the lower articular surface of the radius is normally inclined, or overinclined towards the ulna. These complications can be avoided by use of an operation producing pseudarthrosis of the distal part of the ulna, with fusion of the radio-ulnar joint (Lauenstein) if there is dislocation, radio-ulnar discrepancy or arthritis, or without fusion (Baldwin) if the joint, in spite of keeping normal articular surfaces, has its movement blocked by malunion of a radial fracture.