In this paper, we propose a theoretical model for the error propagation phenomenon generated by a frame loss in a distributed video coding framework. Using rate-distortion functions, we analyze the impact of a frame loss on the average distortion of a group of pictures depending on the position of the lost frame within the GOP, as well as the level of motion in each frame and the quantization errors in the key frames and the Wyner-Ziv frames. This theoretical analysis is fur- ther confirmed by a practical implementation of the DVC framework using different configurations of frame losses.