[Ossification of the Posterior Longitudinal Ligament Found in a Case of Sudden Head-tilt Difficulty following Induction of General Anesthesia].

We report a case of sudden head-tilt difficulty after induction of general anesthesia which was postoperatively diagnosed as ossification of the posterior longitudinal ligament. A 42-year-old man weighing 115 kg was scheduled for emergent laparoscopic appendectomy for acute appendicitis. Prior to induction of anesthesia, the patient could tilt his head, but was unable to do so afterwards. Following mask ventilation with jaw-thrust maneuver, we successfully performed tracheal intubation using the Pentax-AWS Airwayscope. After surgery, he was diagnosed with ossification of the posterior longitudinal ligament by an orthopedist.