Concurrent dorsal dimelia in 160 consecutive patients with congenital anomalies of the hands and feet.

This study was designed to investigate the prevalence of dorsal dimelia in a series of 160 consecutive patients with congenital anomalies of the hands and feet, and to investigate the distribution of dorsal dimelia and the concurrent anomalies. Five cases (3.1%) showed evidence of dorsal dimelia and the distribution of dorsal dimelia was similar to the distribution of concurrent anomalies in all five cases. Another 11 cases of concurrent dorsal dimelia with other congenital anomalies have been reported previously with a positive match in the distributions in all cases. This similarity in the distribution in all 16 reported cases (including the five cases in the current study) is statistically significant. It is concluded that dorsal dimelia in humans is not as rare as it is generally thought to be, and that it may be viewed as an error of dorso-ventral patterning, which occurs in the same distribution as other concurrent anomalies.