Impact of the occiput and external acoustic meatus to axis angle on dysphagia in patients suffering from anterior atlantoaxial subluxation after occipitocervical fusion

• Published in: The spine journal 2019-08, Vol.19 (8), p.1362-1368
• Main Authors: Chen, Taiyong, Yang, Xi, Kong, Weijun, Li, Zhongyang, Song, Yueming
• Format: Article
• Language: English
• Subjects: Adult; Anterior atlantoaxial subluxation; Atlanto-Axial Joint - diagnostic imaging; Atlanto-Axial Joint - surgery; Complication; Deglutition Disorders - epidemiology; Deglutition Disorders - etiology; Dysphagia; Ear Canal - diagnostic imaging; Female; Humans; Joint Dislocations - epidemiology; Joint Dislocations - etiology; Male; Middle Aged; Occipitocervical fusion; Postoperative Complications - epidemiology; Postoperative Complications - etiology; Spinal Fusion - adverse effects; Spinal Fusion - methods
• ISSN: 1529-9430; 1878-1632
• DOI: 10.1016/j.spinee.2019.04.002

Dysphagia is a complication that sometimes occurs after occipitocervical fusion (OCF). An appropriate O-C2 angle (O-C2a) is recognized as a critical factor for preventing dysphagia. The occiput and external acoustic meatus to axis angle (O-EAa) has some advantages over the O-C2a and is now recognized to outperform O-C2a in predicting dysphagia. However, there are no data on this topic from patients with anterior atlantoaxial subluxation (AAS). To evaluate the relationship between the O-EAa and dysphagia in patients suffering from AAS after OCF surgery. A retrospective clinical study. Data from 22 consecutive AAS patients who had undergone OCF were reviewed retrospectively. The outcome measures included the O-EAa, O-C2a, the narrowest oropharyngeal airway space (nPAS), and the morbidity of dysphagia after OCF. Between September 2011 and September 2017, data from 22 consecutive AAS patients who had undergone OCF were reviewed retrospectively. The patients were divided into two groups according to whether they had suffered postoperative dysphagia by face-to-face questioning or telephone interview. Lateral radiographs were analyzed to determine the pre- and postoperative O-EAa, O-C2a, angle formed by the inferior endplate of C2 and the EA-line (C2Ta), and smallest anteroposterior diameter of the oropharynx between the levels of the uvula and the tip of the epiglottis (nPAS). The incidence of dysphagia after OCF was 18.18% (4/22). The pre- and postoperative mean nPAS values were significantly different between the groups (p