Department of Orthopedic Surgery, 13112Tokyo Medical University, Shinjuku-ku, Tokyo, Japan.
J Orthop Surg (Hong Kong). 2020 Sep-Dec;28(3):2309499020960564. doi: 10.1177/2309499020960564.
Cervical ossification of the anterior longitudinal ligament (OALL) occasionally leads to dysphagia by the anterior osteophyte. A recent report explained that the dysphagia after an occipito-cervical fusion is caused by the narrowing of pharyngeal space due to the cranio-cervical malalignment. The purpose of this study was to evaluate the cranio-cervical alignment in patients with OALL complaining of the dysphagia.
The subjects were 11 cases with complaining of dysphagia due to cervical OALL who underwent anterior cervical OALL resection and as control, age-matched 12 cases without dysphagia who have diffuse idiopathic skeletal hyperostosis in cervical spine. All subjects were male, and the mean age was 59.5 ± 9.1 years. The subjects were divided into two groups according to the symptoms of dysphagia (dysphagia, group A; control, group B). The O-C2 angle, C2-C7 angle, and the maximum thickness of OALL and the cranio-cervical alignment (pharyngeal inlet angle; PIA) and swallowing line (S-line) were measured before and after the operation on the lateral cervical radiogram at the sitting position.
Group A showed significantly large maximum thickness of OALL, small cervical range of motion, small O-C2 angle, large C2-C7 angle, and small PIA. The S-line crossed the anterior apex of cervical osteophyte in group A. After OALL resection, dysphagia had improved, PIA had increased, and the S-line uncrossed the apex of cervical vertebrae in all cases.
The prevalence of dysphagia in patients with cervical OALL was influenced by the thickness of osteophyte, cervical mobility, and cranio-cervical alignment.
颈椎前纵韧带骨化（OALL）偶尔会因前骨赘导致吞咽困难。最近有报道称，枕颈融合术后的吞咽困难是由于颅颈失稳导致咽腔空间狭窄所致。本研究旨在评估因颈椎 OALL 而出现吞咽困难的患者的颅颈对线情况。
受试者为 11 例因颈椎 OALL 出现吞咽困难而接受前路颈椎 OALL 切除的患者，并以年龄匹配的 12 例无吞咽困难的弥漫性特发性骨肥厚患者作为对照。所有受试者均为男性，平均年龄为 59.5±9.1 岁。根据吞咽困难症状将受试者分为两组（吞咽困难组，A 组；对照组，B 组）。在坐位侧位颈椎 X 线片上测量 O-C2 角、C2-C7 角、OALL 最大厚度以及颅颈对线（咽入口角；PIA）和吞咽线（S 线），并在手术前后进行测量。
A 组 OALL 最大厚度明显较大，颈椎活动度较小，O-C2 角较小，C2-C7 角较大，PIA 较小。A 组 S 线穿过颈椎前缘骨赘顶点。OALL 切除后，吞咽困难改善，PIA 增加，所有患者的 S 线不再穿过颈椎椎体顶点。
颈椎 OALL 患者吞咽困难的发生率受骨赘厚度、颈椎活动度和颅颈对线的影响。
