Ulna plus variances greater than 3 mm should be treated by ulnar shortening osteotomy. Ulna plus variances associated to malunion of the distal radius should be treated by correction osteotomy of the distal radius.Diagnosis can generally be made by x-rays and MRI. Arthroscopy can confirm diagnosis, and detect or exclude associated lesions. Arthroscopic wafer procedure gives good results in ulna plus variances less than 3 mm. Associated lesions or other pathologies leading to impactions can be addressed in the same arthroscopic session.

The USO is a well-known and established procedure for the treatment of primary and secondary ulnar impaction syndrome. The arthroscopic debridement of TFCC-lesions Type Palmer IIB-E are also well known.Factors which influence the decision-making in between arthroscopic or open surgical procedures are the amount of ulna plus variance, the age of the patient, the structural damages to the TFCC and the configuration of the DRUJ.