In each polytrauma a diaphragmatic rupture is possible. Usually the rupture is located in the central tendon. A cause of the bizarre form of ruptures is the individual arrangement of gaps between the fibres of the central tendon. These fibres are classified in three groups. A rupture is generally on the left side of the central tendon. A further cause of the relative rare rupture on the right side is beside protection by the liver the greater stability on the right side of the central tendon, because fibres are more interlocked. The diaphragmatic rupture of a polytrauma is often overlooked, this number could be reduced by specific diagnostics. The repair of a diaphragmatic rupture is not a problem, an abdominal approach should be preferred. The prognosis depends on extension of concomitant lesions.