A 56-year-old Bourne man was seriously injured early Monday when he lost control of his bicycle and fell onto the roadway of the Bourne Bridge and into the path of a tractor trailer unit, officials said. The bridge was closed for an hour while firefighters extricated the man from under the wheels of the truck’s cab, officials said. According to State and Bourne police, the man was riding his bike northbound about 5:40 a.m. while the truck driver was traveling in the opposite direction. At the crown of the bridge, rhe cyclist lost control, possibly due to gusting winds. The truck driver saw the bicyclist lose control and cut his wheels to the left in an effort to avoid hitting the man, said Bourne police Lieutenant Richard Silvestro.