A clamp has two arms with gripping jaws for supporting and positioning a superelastic osteosynthesis clip, The osteosynthesis clip comprising a web from which two flanges to be inserted into two portions of bone emerge. The clamp also has a component for preventing the jaws from being opened beyond a point at which the angle between the flanges of a clamp supported clip is greater than 90° and a second component for preventing the jaws from being closed beyond a point at which the angle between the flanges and the web is substantially 90°.
