Prevalence, morphology, and morphometry of the pterygospinous bar: a meta-analysis

PURPOSE: The purpose of the study was to analyze the total prevalence, morphologic, and morphometric characteristics of the pterygospinous (PS) bar and its gender and ethnic differences among populations. PS bar is an ossified anatomic structure stretching between the posterior margin of the lateral pterygoid lamina to the angular spine of the undersurface of the sphenoid, with potential clinical implications. There is no consensus in the literature on its prevalence, morphologic, and morphometric characteristics. METHODS: A thorough search of databases was conducted. Data on the prevalence, morphology, i.e., ossification type (complete and incomplete), side, gender, laterality, and morphometrics, of the PS bar were extracted and pooled into a meta-analysis. RESULTS: A total of 35 studies (n = 14,047 subjects) were analyzed. The overall pooled prevalence of a complete PS bar was 4.4% (95% CI 3.7–5.1), while the overall pooled prevalence of an incomplete PS bar was significantly higher (11.6% [95% CI 8.5–15.2]). A complete PS bar was more prevalent among males and was more commonly unilaterally, on the left side. CONCLUSION: The overall prevalence of PS bar is quite common. It could be of importance for clinicians who should consider its potential presence when planning surgical approaches to the retropharyngeal and parapharyngeal space. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s00276-019-02305-9) contains supplementary material, which is available to authorized users.