Out of position (OOP), in crash testing and car accident medical literature, indicates a passenger position which is not the normal upright and forward-facing position.[1] For example, a common case observed in crashes is the position of an occupant when reaching for the car radio,[2] or panic braking in unbelted passengers.[3] The concept is of interest because small changes in a passenger's position can have profound effects on the actual kinematic response, especially in rear impacts, as shown both in practical testing and theoretical models.[1]