Distributed surgical virtual environments are desirable since they substantially extend the accessibility of computational resources by network communication. However, network conditions critically affects the quality of a networked surgical simulation in terms of bandwidth limit, delays, and packet losses, etc. A solution to this problem is to introduce a middleware between the simulation application and the network so that it can take actions to enhance the user-perceived simulation performance. To comprehensively assess the effectiveness of such a middleware, we propose several evaluation methods in this paper, i.e., semi-automatic evaluation, middleware overhead measurement, and usability test.