Ankylosing hyperostosis in American blacks: a longitudinal study.

We studied 63 consecutive patients with ankylosing hyperostosis to investigate any possible difference in clinical or roentgenographic features between whites and blacks. Our data suggest that (a) the disease may not be less common among blacks, (b) presence of extraspinal hyperostosis in this disease may be more frequent in black patients, and (c) the known male preponderance of the disease among whites may not occur among blacks.