The authors describe a hinge distraction apparatus which allows physiological movement of joints following surgical procedures such as arthrolysis or arthroplasty. The apparatus maintains some space between the bone ends and provides lateral stability. It is based on the principles of external fixation. The apparatus has been used for ankles, knees, and elbows. Thirty-eight patients were operated on. The technique is fully described. The results on experimental work in the dog are given. At the ankle, the authors have shown that the use of the apparatus allows the formation of fibrous tissue between the bone ends. The indications and results obtained at the level of the knee and elbow are discussed.