Henman has gone down because Alex Corretja of Spain, who reached the final of the Monte Carlo Open, has moved up to 13. Both Henman and Rusedski, inactive lately after injuries, hope to return within two weeks.
Rusedski intends to play in Hamburg next week and Henman at the Italian Open in Rome a week later. Mark Petchey is the only other British man in the top 200 in the world rankings, at 191, while Chris Wilkinson is 206 and Andrew Richardson is 234.
Steffi Graf, who has been out for three months, has confirmed she will put her knee to the test in the German Open in Berlin, which starts on 12 May.
Judith Wiesner, 31, Austria's world No 17, will retire at the end of the year. She has been out with a virus since mid-March.