The 29-year-old, who has been sidelined due to medial ligament damage since limping out of the 2-2 draw at Birmingham on December 7, was named in the Under-21s side for their league clash with Arsenal at Rockliffe Park.
Kamara, who joined Boro from Sporting Kansas City in September last year, had scored four senior goals before being forced to sit out the last six Sky Bet Championship games and the 2-0 FA Cup third-round defeat by Hull City.
Defender Adam Reach was also due to join him following his return from his spell at League One Shrewsbury.
The 20-year-old made 24 appearances for the Shrews after being sent out on loan by former boss Tony Mowbray in August.
He will now have a chance to impress new manager Aitor Karanka and try to force his way into the senior team.