The Airbus A320-214 had completed the pushback and started the engines on Spot No. 2. At approximately 12:37 local time, the taxiing commenced after the crew received clearance from ground personnel. When the aircraft had moved approximately 10 meters, ground support personnel positioned themselves in the aircraft’s path and made a visual signal to the crew to stop, as they noticed that the communication connection door was left open. The crew indeed stopped the aircraft, and as a result of the deceleration, a Cabin Crew Member who was standing fell onto the forward galley and sustained injuries. The crew became aware of the situation and suspended the flight, which was resumed two (2) hours later. The crewmember, suffered a serious spinal injury. As a result of the injury, the flight attendant received a total of 100 days of disability. The investigation determined that the accident occurred due to the following probable cause: Failure of the ground support personnel to adhere to dispatch procedures and checks by neglecting to close the access door of the External Power / Communication Jack, a task that was delegated to a Technical Apprentice by a Licensed Technician (instructor). As a contributing factor, the investigation found: Unsecured position of the Cabin Crew Member, which resulted in her falling during an unexpected and abrupt braking by the flight deck crew.