Police said two men were involved and one was found to be in possession of a machete blade.
The attack was in the vicinity of Risbygate Street and Springfield Road.
Police are appealing for witnesses after the driver of a BMW did not stop after a collision.
The 82-year-old woman was attacked and robbed on Thursday, June 27.
Police arrested two men yesterday (Thursday, July 11) after a stop and search
The woman was strangled until she passed out.
The incident was on Monday, July 1.
The incident was at about 1pm.
Police are appealing for anyone with information to contact them.
The trail celebrates the 200th anniversary of the Theatre Royal.
Fines were imposed in the men's absence.