Tenotomies, tendon transfers or nerve injuries can result in partial or complete loss of the flexor carpi radialis (FCR) or flexor carpi ulnaris (FCU) function. The aim of this study was to observe alterations in the distribution of muscle forces at the wrist due to the absence of each of these flexors. Cyclic planar and complex wrist motions were actively simulated in cadaveric specimens by applying tensile loads to six muscle tendons using a validated physiological wrist simulator. The absence of FCR or FCU resulted in higher forces in synergists, coupled with lower forces in antagonists, and an overall decrease in the total force of all tendons. Thus, alterations in wrist tendon forces following reconstructive procedures utilising a tendon may have clinical implications, such as muscle fatigue or reduced strength.