In Vivo Contact Mechanics of the Distal Radioulnar Joint of the Normal Wrist Compared to Scapholunate Injury and Surgical Repair

Abstract

The distal radioulnar joint (DRUJ) is a joint of the wrist which allows forearm rotation and force transmission in the upper limb while preserving stability independent of flexion and extension of the forearm and wrist. The DRUJ is a frequently injured joint in the body. Conditions affecting the joint could be positive ulnar variance (Ulnar Impaction Syndrome) or negative ulnar variance (ulnar impingement), which may be congenital or may result from a poorly reduced distal radius fracture or both bone forearm fracture. The DRUJ is also adversely affected by other injuries near the joint. In fact, a significant correlation has been found between negative ulnar variance and scapholunate dissociation [1, 2, 3]. While this could be a predisposing factor, the associate also leads to the question of whether or not scapholunate dissociation may cause changes in the radioulnar joint mechanics. Altered joint mechanics are highly associated with onset of secondary osteoarthritis. An understanding of in vivo distal radioulnar joint contact mechanics in the normal and pathological wrist could help physicians make better clinical recommendations and improve treatment for the primary injury and avoid DRUJ pathology. Successful treatment may possibly reduce risk of or prevent the onset of osteoarthritis.