Fig. 3

Blood flow in patient limbs on day 28 after the initiation of CO₂ therapy. The horizontal axis indicates the time course. Blood flow was measured continuously from prior to the commencement of the CO₂ therapy (PRE) to 20 min after (POST) a 20-min session of the CO₂ therapy. The vertical axis shows the blood flow. The affected bone (femur or tibia) and whether the fracture is a fresh fracture or a fracture with nonunion are indicated. The solid line shows the blood flow in the fractured limb and the dotted line shows the blood flow in the contra–lateral healthy limb. Filled circles on the lines indicate the time point of the start and end of the CO₂ therapy. a Blood follow measured at the fracture level. b Blood follow measured at a point 5 cm from the fracture level