Correlation of morphological and radiological characteristics of degenerative disc disease in lumbar spine: a cadaveric study

Background: Intervertebral disc (IVD) degeneration plays a crucial role in the pathophysiology of low back pain. Several grading systems have been developed for both morphological and radiological assessment. The aim of this study was to assess the morphological and radiological characteristics of IVD degeneration and validate popular radiological Pfirrmann scale against morphological Thompson grading system. Material and methods: Full spinal columns (vertebrae L1-S1 and IVD between them) were harvested from cadavers through an anterior dissection. MRI scans of all samples were conducted. Then, all vertebral columns were cut in the midsagittal plane and assessed morphologically. Results: A total of 100 lumbar spine columns (446 IVDs) were included in the analysis of the degeneration grade. Morphologic Thompson scale graded the majority of discs as grade 2 and 3 (44.2% and 32.1%, respectively), followed by grade 4 (16.8%), grade 1 (5.8%) and grade 5 (1.1%). The Radiologic Pfirrmann grading system classified 44.2% of discs as grade 2, 32.1% as grade 3, 16.8% as grade 4, 5.8% as grade 1 and 1.1% as grade 5. The analysis on the effect of age on degeneration revealed significant, although moderate, positive correlation with both scales. Analysis of the agreement between scales showed weighted Cohen’s kappa equal to 0.61 (p<0.001). Most of the disagreement occurred due to a 1 grade difference (91.5%), whereas only 8.5% due to a 2 grade difference. Conclusions: With the increase of the prevalence of intervertebral disc disease in the population, reliable grading systems of IVD degeneration are crucial for spine surgeons in their clinical assessment. While overall there is agreement between both grading systems, clinicians should remain careful when using Pfirmann scale as the grades tend to deviate from the morphological assessment

The pterygoalar bar: A meta-analysis of its prevalence, morphology and morphometry

Purpose The pterygoalar (PA) bar is a bony bridge resulting from the partial or complete ossification of a PA ligament. The aim of this meta-analysis was to systematically analyze and provide the most comprehensive data on the prevalence, morphology and topographical anatomy of the PA bar. Materials and methods A comprehensive search of the major electronic databases (PubMed, Embase, ScienceDirect, SciELO, BIOSIS, and Web of Science) was conducted in order to identify relevant studies. Studies reporting the prevalence, side of occurrence, gender dimorphism and morphometry of the PA bar were included in the current study. Results A total of 25 articles (n = 16,168 subjects) were included in the meta-analysis. The overall pooled prevalence of the complete PA bar was 4.4% (95% CI: 3.0–6.0) and of the incomplete was 8.4% (95% CI: 4.6–13.3). The PA bar was most often observed unilaterally, on the left side. Analysis of geographical subgroups revealed considerable differences, with the lowest prevalence rates in Europe for both incomplete and complete PA bars. Conclusions Considering the prevalence and anatomical characteristics of the PA bar, caution is recommended while planning or performing transfacial needle approach to the foramen ovale and when considering a differential diagnosis for nerve compression or entrapment syndromes. © 2017 European Association for Cranio-Maxillo-Facial Surger