The anatomy of phrenic nerve termination and the motor innervation of the diaphragm.

The more frequent diagnosis of sliding hiatal hernia has focused surgical attention on the crural fibres of the diaphragm. The part played by the muscular hiatus in " the closing mechanism " between stomach and oesophagus is, however, still undecided. Various experimental methods of dividing crural muscle and phrenic nerve have been tried at different centres to evaluate the importance of the muscular hiatus. These sections and the relevant clinical considerations necessitate a precise knowledge of phrenic nerve termination, and therefore a series of anatomical and experimental investigations was carried out in man as well as in the common laboratory animals.