 Widening of the single tibial tunnel following ACL surgery with quadrupled hamstrings autograft may contribute to failure of the graft andor present technical challenges secondary to bone loss in a revision setting Getelman, 1999. As such, efforts should be made to minimize the incidence and magnitude of tibial tunnel widening without sacrificing the biomechanical properties of the graft construct. The purpose of this investigation is to examine the tibial tunnel widening relationship between bioabsorbable interference screws composed of poly-L-lactic acid PLLA alone and composite bioabsorbable interference screws composed of poly-L-lactic acid embedded with beta tricalcium phosphate PLLATCP utilized as tibial fixation devices. 