Fifty-two patients undergoing a single-level unilateral MIS TLIF were evenly randomized into 2 cohorts as follows : the Actifuse cohort received Actifuse combined with 5 mL of bone marrow aspirate ( n = 26 ; 50 % ) , whereas the rhBMP cohort received 4.2 mg of rhBMP-2 ( n = 26 ; 50 % ) .