A comparison of two indices for ulnar translation and carpal height in the rheumatoid wrist.

The indices for ulnar translation described by Chamay et al. (1983, Annales de Chirurgie de la Main, Vol. 2, pp. 5-17), and Bouman et al. (1994, Journal of Hand Surgery Vol. 19B, pp. 325-329), and for carpal height described by Youm et al. (1978, Journal of Bone and Joint Surgery, Vol. 40A, pp. 423-431) and Bouman et al. (1994) were compared in pre- and postoperative wrist X-rays of 91 patients with rheumatoid arthritis undergoing radiolunate arthrodesis. Both indices described by Bouman had a higher applicability and sensitivity than the Chamay and Youm indices and are recommended for use with the rheumatoid wrist. However false-negative values may result when the Bouman index for ulnar translation is used to follow up radiolunate arthrodesis.