A short nail for treatment of an epiphyseal fracture close to a joint in a long bone includes a two part nail supporting body comprising a main body having a transverse through-bore and releasably attached to a stub body. The stub body has an end that has a diaphyseal slant. The stub body and the lateral slant form part of a diaphyseal anchor which is attachable to the main body via the stub body and which has a flat connecting web that has an oblique orientation and ending laterally in a plane with the diaphyseal slant. A connecting device rigidly and releasably connects the main body and the stub body together. An anchoring device fixes the flat web in flat abutment against the diaphysis. A fixation pin is insertable into the transverse through-bore in a crossed arrangement with, and at a fixed angle to, the supporting body in the state of treatment of the fracture. The fixation pin includes a mechanism to protect against axial movement of the pin.