Volar 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 better visualization of small, complex anatomic structures, such as the carpal ligaments. The purposes of this study were twofold: (1) to determine if the volar carpal ligaments can be consistently visualized when using 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 volar 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 major volar carpal ligaments. The size, shape, orientation, and right-to-left symmetry of the ligaments were determined from the reconstructed two-dimensional images.

Results: Six of the eight volar ligaments were visualized in more than 95% of the 50 wrists: the radioscaphocapitate, radiolunotriquetral, radiolunate, ulnolunate, ulnotriquetral, and triquetroscaphoid ligaments. The radioscaphoid and radioscapholunate ligaments were less well defined and were recognizable as ligaments in only 66% and 26% of wrists, respectively.

Conclusion: The major volar carpal ligaments can be visualized consistently with three-dimensional Fourier transform MR imaging techniques and multiplanar reconstructions. The volar carpal ligaments are usually symmetric between the right and left sides; therefore, MR images of a patient's injured wrist can be compared with MR images of the contralateral wrist. The size and shape of the volar carpal ligaments shown in this article can be used as a basis for comparison when patients with suspected ligamentous injuries are examined. This information will be useful for detecting ligamentous injuries on MR images.