Diplopia developed by cervical traction after cervical spine surgery.

Diplopia is a rare complication of spine surgery. The abducens nerve is one of the cranial nerves most commonly related to diplopia caused by traction injury. We report a case of a 71-year-old woman who presented with diplopia developing from abducens nerve palsy after C1-C2 fixation and fusion due to atlantoaxial subluxation with cord compression. As soon as we discovered the symptoms, we suspected excessive traction by the instrument and subsequently performed reoperation. Subsequently, the patient's symptoms improved. In other reported cases we reviewed, most were transient. However, we thought that our rapid response also helped the patient's fast recovery in this case. The mechanisms by which postoperative diplopia develops vary and, thus, remain unclear. We should pay attention to the fact that the condition is sometimes an indicator of an underlying, life-threatening condition. Therefore, all patients with postoperative diplopia should undergo thorough ophthalmological and neurological evaluations as well as careful observation by a multidisciplinary team.