The other class of synovial joints are the hinge joints. A hinge joint works like a hinge fixed to a door or window. A hinge joint allows bones to move in one direction, that is only a backward and a forward motion. In the human body, we can find the hinge joints between the bones of the fingers (phalanges) and between the inner bone of the forearm and the humerus at the elbow. The synovial membrane secretes lubricant to keep these joints lubricated.