Flat bone plate for use in minimally invasive osteosynthesis

A flat bone plate for use in a minimally invasive osteosynthesis, the flat bone plate having a shape which does not hinder the supply of blood from muscles to a fracture. The flat bone plate has a first affixation plate (11), a first connection section (12), a support plate (13), a second connection section (14), and a second affixation plate (15) which are arranged in that order in the longitudinal direction and are integrated together. The first affixation plate (11) and the second affixation plate (15) are respectively provided with screw through-holes (16) and also respectively provided with curved surfaces (11a, 15a) which make contact with a bone. The support plate (13) has a curved surface which makes contact with muscles. The first connection section (12) connects the first affixation plate (11) and the support plate (13), and the second connection section (14) connects the support plate (13) and the second affixation plate (15). The curved surface of the support plate (13) is positioned above the curved surfaces of the first affixation plate (11) and the second affixation plate (15) by the first connection section (12) and the second connection section (14), the curved surface of the support plate (13) making contact with the muscles, the curved surfaces of the first and second affixation plate (13, 15) making contact with the bone.