The New Zealand-born hooker has been out of action since September 11 following a series of back spasms
The New Zealand-born hooker, who earlier this year led England to a Six Nations Grand Slam and a 3-0 series win in Australia, has been out of action since September 11 following a series of back spasms.
However, he has now returned to full training and Northampton backs coach Alan Dickens said Wednesday: "Dylan's been injured. He's on the route back.
"He trained fully last week. He's trained fully this week, it's just dependent on how he reacts. He's there or thereabouts," he added of this weekend's match awa to French club Castres.
Hartley's increasing fitness is welcome news for both Northampton, looking to back up their 16-14 win in last week's Champions Cup opener against Montpellier, another French club, and England, who open their end-of-year Test series against South Africa at Twickenham on November 12.