[Hypoglossal nerve paralysis following tonsillectomy]

Lesions of the lingual nerve and the glossopharyngeal nerve following tonsillectomy are rare but can be expected because of their anatomical course. What is extremely rare is a lesion of the hypoglossal nerve, whose course behind the carotid artery protects it from direct injury. The few cases described in the literature are thought to have been caused by inflammatory processes. It became necessary to look for other causes when, after a regular tonsillectomy, a hypoglossal palsy became evident in the absence of any inflammation. In an experiment, it was possible to demonstrate that both the insertion of a spatula and of an intubation spatula caused a strain of the hypoglossal nerve when the spatulas were inserted in the lateral lingual region. The nerve was distended by as much as 1.3 cm. The more the head was reclined, the more the nerve was distended. It would seem probable that this extension of the hypoglossal nerve causes its palsy following tonsillectomy.