Dorsal carpal ligaments of the wrist: normal appearance on multiplanar reconstructions of three-dimensional Fourier transform MR imaging.

OBJECTIVE: Three-dimensional Fourier transform MR imaging techniques can produce much thinner contiguous slices than are obtainable with standard two-dimensional Fourier transform MR imaging techniques. The improved spatial resolution and capabilities for interactive multiplanar displays allow improved visualization of small, complex anatomic structures such as the carpal ligaments. The purposes of this study were twofold: (1) to determine if the dorsal carpal ligaments can be visualized consistently with three-dimensional Fourier transform MR imaging techniques with multiplanar reconstructions and (2) to evaluate the size, shape, orientation, and right-to-left symmetry of the dorsal carpal ligaments in both wrists of 25 asymptomatic volunteers as a basis for future comparison when patients with suspected ligament injuries are seen. SUBJECTS AND METHODS: Both wrists of 25 asymptomatic volunteers were imaged with a three-dimensional Fourier transform MR imaging technique with commercially available equipment. A three-dimensional graphic workstation was used to reconstruct oblique two-dimensional images in the long axes of the radiotriquetral and dorsal intercarpal ligaments in all 50 wrists. The size, shape, orientation, and right-to-left symmetry were determined by the author using the reconstructed two-dimensional images.
RESULTS: The radiotriquetral ligament and dorsal intercarpal ligament were visualized in all 50 wrists. The radiotriquetral ligament consisted of a single band arising from the distal radius (next to Lister's tubercle) in 84% and had dual origins from the styloid process of the radius and Lister's tubercle in 16%. The dorsal intercarpal ligament consisted of a single broad band in 14% of wrists, was a branched structure with separate triquetroscaphoid and triquetrotrapezial fascicles in 44%, had completely separate triquetroscaphoid and triquetrotrapezial fascicles in 38%, and had a triquetrotrapezial fascicle larger than the triquetroscaphoid fascicle in 4%. The dorsal intercarpal ligamentous anatomy was symmetric in 16 of 25 volunteers.
CONCLUSION: The major dorsal carpal ligaments can be visualized consistently when using three-dimensional Fourier transform MR imaging techniques and multiplanar reconstructions. The dorsal carpal ligaments are usually symmetric in size and morphology; therefore, MR images of the contralateral wrist may be used for comparison with MR images of a patient's injured wrist. The size and shape of the dorsal carpal ligaments are described for comparison with findings in patients who have suspected ligamentous injuries.