
The 32-year-old has won just three matches this season while struggling with the back pain which has plagued him for several seasons. Henman withdrew from this week's New Haven event.
The number 92 is signed on for Britain's Davis Cup tie at Wimbledon against Croatia from September 21 but has entered no ATP events for the autumn.
"Playing on hard courts is a lot tougher on the body and my back hasn't reacted as well as I wanted," Henman said after losing in the first round last week in Cincinnati.
"My goal now is to try to get as much treatment on it as possible before the start of the US Open."
London's Times reported that the veteran, who once stood fourth in the world in July, 2002, hopes to make a start at the Open to begin bringing down the curtain on his career.