On June 17, 2002, about 1950 eastern daylight time, a flight attendant sustained minor injuries while closing the main cabin door on a standing Dornier 328, N439JS operated by PSA, dba U.S. Airways Express, at Ronald Regan Washington National Airport (DCA), Washington, District of Columbia. Two flight crew members, 10 passengers, and one other flight attendant were not injured. Visual meteorological conditions prevailed for the flight scheduled to be conducted under 14 CFR Part 121. According to the operator, the flight attendant was attempting to lock the main cabin door after ground service personnel had closed it flush with the fuselage. While the flight attendant was locking the door from inside the airplane, ground service personnel locked it from the outside of the airplane, catching the flight attendant's hand, fracturing her finger and wrist. The procedure for the Dornier 328 aircraft was for ground personnel to close the door flush with the fuselage, and the flight attendant to lock it. The flight attendant did not report any malfunction with the main cabin door.