This diagnostic image is a lateral radiograph of the wrist and distal forearm demonstrating the radiographic assessment of the distal radioulnar joint (DRUJ) using the Mino method. The image shows the distal radius, distal ulna, and carpal bones in a lateral profile. Two vertical reference lines are drawn parallel to the longitudinal axis of the radius, originating from the volar and dorsal margins of the distal radial articular surface. Overlaid measurements in yellow indicate a quantitative analysis of ulnar head displacement. A specific measurement of 7.3 mm highlights the distance of the dorsal subluxation of the ulnar head relative to the dorsal reference line. According to the Mino criteria, instability or subluxation is diagnosed when more than 25% of the ulnar head width lies outside these boundaries. This visual demonstrates dorsal DRUJ subluxation, a significant finding in cases of wrist trauma or ligamentous instability, typically used by orthopedic and radiology professionals to evaluate joint congruity.

This diagnostic comparison contains two cross-sectional axial CT scans of the wrist, demonstrating the distal radioulnar joint (DRUJ) in neutral position. Both images utilize Mino's criteria, with two parallel reference lines drawn along the dorsal and palmar cortical borders of the distal radius to assess ulnar alignment. The 'Preoperative' image shows the ulnar head displaced dorsally, lying outside the space defined by the tracing lines, which indicates dorsal subluxation of the DRUJ. The 'Postoperative' image displays the ulnar head successfully reduced and centered between the two reference lines, signifying restored joint congruency following surgical reconstruction. These images serve as an educational tool for evaluating TFCC injury-related instability and the efficacy of anatomic radioulnar ligament reconstruction. Key anatomical features visible include the distal radius sigmoid notch, the ulnar head, and internal bony trabecular patterns.

A multi-panel medical image sequence illustrating the management of distal radioulnar joint (DRUJ) instability. Subfigures A and B are preoperative anteroposterior and lateral X-rays of the wrist showing malunion of a distal radius fracture and associated DRUJ subluxation. Subfigure C is an intraoperative clinical photograph showing a palmaris longus tendon graft being used for ligament reconstruction. Subfigures D and E are postoperative anteroposterior and lateral radiographs showing surgical correction. These images demonstrate internal fixation with a volar locking plate and screws on the distal radius following a corrective osteotomy. Restored anatomical alignment of the radius and ulnar head is visible. Key diagnostic features include the presence of radiolucent bone tunnels in the distal radius and ulnar head, indicating the pathways for the ligament reconstruction. The image provides educational value for orthopedic surgery, specifically in treating distal radius malunion and chronic DRUJ instability through combined bony and soft tissue reconstruction.

Axial plane computed tomography (CT) scans of bilateral wrists comparing the congruity of the distal radioulnar joint (DRUJ) in different forearm rotations. Figures A and B represent the right wrist in supination and pronation, respectively, demonstrating persistent dorsal subluxation of the ulnar head relative to the sigmoid notch of the radius. This finding is characteristic of an unstable DRUJ following a Galeazzi-type injury. Figures C and D show the left wrist in supination and pronation, illustrating near-normal anatomical congruity where the ulnar head remains appropriately seated within the radial notch throughout the rotational range. Image C also contains a cross-section of an external fixator pin. These diagnostic images are used to assess post-surgical stability and alignment in orthopedic trauma cases involving radius fractures with associated DRUJ disruption.