A method and device for measuring blood flow in the bone after a fracture, wherein a hole is drilled into the bone. The method includes the steps of inserting the metal sleeve of an osteoscope into the hole; inserting the optics of an osteoscope into the metal sleeve and focused on the cavity created by the drill; filling the device and the cavity with a physiological solution such that the pressure of the solution is above the systolic blood pressure; decreasing the pressure of the solution while observing the cavity through the osteoscope, and recording the pressure in the system at the commencement of bleeding.