The British Lions No8 was injured in Bath’s opening game of the Aviva Premiership season at Northampton Saints.
A scan revealed the damage will keep him out for between six and eight weeks, ruling him out of the opening two rounds of the European Challenge Cup.
But the 25-year-old forward, who has played 61 of the last 67 Wales Tests he was available for, is expected to return to fitness in time for the Series that kicks off on November 5 against Australia at the Principality Stadium.
Wales then face Argentina who rattled world champions New Zealand in Hamilton last weekend. The Pumas, fresh from a 26-24 win over South Africa, shook the All Blacks with a try inside three minutes by Santiago Cordero.
And they trailed by just two points at 24-22 in the 50th minute through the boot of Nicolas Sanchez before a late rally by the hosts sealed an emphatic win.
Wales also face Japan on November 19 and end the series against the Springboks on November 26.
South Africa led the Wallabies in Brisbane with two early tries by Warren Whiteley and Johan Goosen before succumbing 23-17.
