Reliability of biomechanical mensuration methods of the sagittal cervical spine on radiography used in clinical practice: A systematic review of literature

Biomedical literature assessing reliability of mensuration of sagittal cervical spine alignment on radiographs is limited. This review aims to systematically identify and assess reliability studies on biomechanical assessments of the sagittal cervical spine used in clinical practice. The study design was registered with PROSPERO (CRD42023402990). Funding was from CBP, Non-Profit (Eagle, ID, USA). Inclusion criteria involved studies in English with: human subjects, radiography of the sagittal cervical spine, and reliability analysis on biomechanical mensuration of sagittal cervical spine. Exclusion criteria involved studies with: geometric modeling, animals, cadavers, phantom mannequins, and non-radiographic studies. Pubmed, CINAHL, AltHealth Watch, and Web of Science databases were searched from inception through January 24, 2023. The quality appraisal tool for studies of diagnostic reliability (QAREL) assessed bias risk. Results are presented following the synthesis without meta-analysis (SWiM) in systematic reviews guidelines. Scrutiny of inclusion criteria yielded 51 articles. Results are limited due to heterogeneity of the various mensuration methods and statistical analyses. The preponderance of evidence found good to excellent reliability. The results of this systematic review show that sagittal radiographic mensuration of cervical spine biomechanics and alignment is a reliable method for the diagnosis and management of spine conditions in clinical settings.