Dislocation of Bilateral Temporomandibular Joints after Occipito-Cervical Fusion Following Endonasal Endoscopic Resection of Chordoma

Introduction: Occipito-cervical (OC) fusion is indicated for instability due to various pathologies including removal of skull base tumors from the craniocervical junction. Post-operative complications of OC fusion include dyspnea and dysphagia. Studies have acknowledged the reduction of oropharyngeal space after fusion as well as an increased likelihood of dysphagia if patients are fused in a hyperflexed position. We report a patient who developed temporomandibular joint dislocation with malocclusion due to OC fusion after chordoma resection.

Case Presentation: Patient presented as a 20-year-old male with 1.5 years of dysarthria, dysphagia and tongue deviation to the left and 3 weeks of imbalance and incoordination. An MRI was performed showing a large clival lesion. He underwent an endoscopic endonasal transclival and transcondylar approach for excision with pathology consistent with chordoma. The patient underwent fusion of the occiput to C6 on the following day. Post operatively, the patient had trouble with oral intake due to Class III occlusion, nasopharyngeal velopalatal insufficiency, trismus and dysphagia. Physical examination revealed Class III malocclusion and trismus. Endoscopic exam showed a well healing clival defect with noticeable velopalatal insufficiency. A CT scan was obtained showing anteriorly displaced and subluxed bilateral temporomandibular joints.

Discussion: Complications after OC fusion include dyspnea from upper airway obstruction and dysphagia due to a narrowed oropharyngeal space. TMJ dislocation has never been documented from OC fusion, but is possible with patients who are fused in a hyperflexed position. Studies have shown that the ideal post-operative O-C2 angle should be within 2 degrees of a neutral position. This patient was fused 7 degrees more flexed compared with his pre-operative neutral position. Over-flexed fusion can result in anterior dislocation of the TMJ resulting in difficulty chewing due to Class III occlusion, trismus, and dysphagia.

Conclusion: OC fusion must be done while keeping in mind the patient's neutral head position. If patients are fused in a hyperflexed position, symptoms such as dysphagia and dyspnea and even TMJ dislocation are possible.

Publication History

Article published online:
15 February 2022