“It will be wonderful to have someone with Craig’s experience join the Knights for the remainder of the year,” CEO Matt Gidley said.
“We have obviously had a number of injuries this season and Craig can cover players like Danny (Buderus) and Kurt (Gidley).
“We are sure Craig's commitment and competitiveness will be well received by our Members and supporters.”
In a World Cup year, Gower can also test himself in the NRL prior to taking part in Italy's World Cup campaign.
Gower is expected to arrive in Newcastle early next week.