The purpose of this study was to investigate the effects of localized muscle fatigue on the knee joint kinetics during reactive recovery efforts from a slip perturbation. Sixteen healthy young participants were recruited to walk across an unexpected slippery vinyl floor surface in two different sessions (Fatigue and No fatigue). Kinematic and kinetic data were collected using a three-dimensional video analysis system and force plates during both sessions. An inverse dynamic model was developed to assess joint moment and joint power of the knees during reactive recovery period of slip-induced falls. The results demonstrated an increase in the peak knee joint moment and peak knee joint power generation in the fatigue slip trials. There were four reported falls in the fatigue session. The study concluded that localized muscle fatigue adversely affects the knee joint kinetics and can be considered a risk factor for slip induced falls. These findings provide new insights to the biomechanical relationship between knee kinetics and localized muscle fatigue.