Ulnar impaction syndrome in the ulnar negative and neutral wrist. Diagnosis and pathoanatomy.

Although the ulnar impaction syndrome occurs most commonly in the ulnar positive wrist, it can also occur in wrists with either ulnar negative or neutral variance. Dynamic increases in ulnar variance may accompany forceful grip and pronation, but diagnosis of the ulnar impaction syndrome can be difficult nonetheless. This report further substantiates the occurrence of this problem in wrists with neutral and negative variance, and provides a description of diagnostic findings and pathoanatomy.