Walking frame

After spending a total of 936 years navigating the sewers of Tersurus, the Master used a walking frame to pursue the Ninth Doctor and Emma before being rejuvenated by Dalek technology. (TV: The Curse of Fatal Death)

Behind the scenes
In NOTVALID: Doctor Who 3 - The Third Motion Picture, when he reached old age, Dr. Who was given a walking frame which he soon turned into a super-speeded turbo-charged walking frame.