A surgical instrument for fitting a U-shaped osteosynthesis clip having two side bars linked together at the proximal ends by a transverse bar, the transverse bar and the proximal portions forming a proximal region of the clip, the instrument including: at least one recess intended for provisionally receiving the proximal region of the osteosynthesis clip, the distal ends of the two side bars projecting from the instrument； at least blocking means capable of preventing the translation movement of the transverse bar in the proximal and distal directions； at least anti-rotation means preventing the clip from rotating about the transverse bar； and spacing means capable of engaging with the proximal region in order to increase the distance between the distal ends of the two side bars. The invention also relates to a kit including such an instrument and to a clip intended for being received in such an instrument.
