Introduction & Background: Pain and tenderness are common in the palmar and ulnar aspects of the wrist in the area of the pisiform bone. When chronic, this pain may be due to a tendinopathy at the insertion site of the ulnar flexor tendon, carpal fractures, or osteoarthritis of the pisotriquetral joint (PTJ). The PTJ is the second most common site of osteoarthritis in wrist after the scaphotrapezial joint, if the first carpometacarpal joint is excluded. Instability of the PTJ is a recognized complication of osteoarthritis of this joint. Degenerative changes of the PTJ often re-main undiagnosed at clinical and radiographic evaluations. Although they are not usually per-formed, several methods for PTJ imaging have been proposed. A profile view can be obtained when the hands are placed in 300 degrres of supination, allow-ing evaluation of the joint and adjacent bone. Arthro-graphy of the PTJ has also been used alone or in com-bination with radiocarpal joint arthrography to evaluate intra-articular abnormalities of the PTJ. Computed tomography (CT) and CT-arthrography allow more precise visualization of this joint. These imaging methods offer more thorough analysis of the articulation but are limited because of their lack of soft-tissue contrast. A potential role of magnetic resonance (MR) imaging in the assessment of abnormalities of the PTJ has been explored in a few investigations, although to our knowledge no report exists that details the possible role of MR-arthrography in the evaluation of the PTJ. The purpose of our study was to evaluate the MR im-aging and MR arthrographic findings of the PTJ and the contribution of these examinations to the assess-ment of osteoarthritis of this joint.