Toward an Improved Wrist View: Qualitative and Quantitative Investigation of the 20° Axial Lateral Wrist X-Ray

In standard lateral wrist radiographs, the radiocarpal joint is often obscured because of the angulation of the radial styloid process. A modified lateral projection at a 20° angle has been shown to demonstrate the distal radius in profile in postoperative patients without superimposing of the orthopedic hardware used in open reduction and internal fixation procedures over the wrist joint. We assessed whether this 20° axial-lateral view is advantageous in a wider patient group.

Consenting adults receiving wrist radiographs in a tertiary hospital radiology department for any indication underwent posteroanterior, posteroanterior-oblique, 0° lateral, and 20° lateral views. A musculoskeletal radiologist and a radiology technologist, blinded to clinical data and to which view was 0°/20°, both evaluated 0°/20° images in random order for whether the radiocarpal joint was obscured by radial styloid, radiocarpal articular margins, or ulnar styloid process, and which view was preferred.

In 124 cases, the radiocarpal joint was shown clearly on more 20° than 0° views (75/124 vs. 23/124, P < .001). Orthopedic hardware obscured joint lines in fewer 20° than 0° views (12/124 vs. 28/124, P < .001). There was a trend to the ulnar styloid process obscuring part of the radiocarpal joint less in 0° view (28/124 vs. 78/124 in 20°; P = .088), primarily in 20° laterals of wrists with positive ulnar variance. The 20° view was preferred by the radiologist in 76% (95/124) and preferred by the technologist in 83% (104/124).

The 20° lateral view was superior to the current 0° lateral view in a wide range of patients, with the radiocarpal joint obscured significantly less by hardware or adjacent anatomy, and preferred by both the blinded radiologist and technologist.