Romberg's sign: development, adoption, and adaptation in the 19th century.

In the first half of the 19th century, European physicians-including Marshall Hall, Moritz Romberg, and Bernardus Brach-described loss of postural control in darkness of patients with severely compromised proprioception. Romberg and Brach emphasized the relationship between this sign and tabes dorsalis. Later, other neurologists evaluated the phenomenon in a broader range of neurologic disorders using a variety of simple but increasingly precise and sensitive clinical tests. Although now known as Romberg's sign, among neurologists in the late 19th century this phenomenon was sometimes credited to Romberg, sometimes to both Brach and Romberg, and sometimes discussed without attribution.