A systematic review and meta-analysis of 3D and 4D full body scanning to assess spinal curvature and body posture by using surface topography in adults

Spinal deformities present significant challenges, and there is a notable gap in the literature regarding postural analysis despite the availability of numerous scanning techniques. A shift towards patient-centered care emphasizes the development of non-invasive 3D and 4D (time-series 3D scanning) scanning methods excluding MRI and CT. This systematic review aims to gather comprehensive information on these techniques, noting the absence of similar studies in the scientific community. The review explores the different 3D and 4D methods in posturography for patients with spinal deformities and questions about whether possible 4D analysis could be superior to 3D. The systematic review was conducted in accordance with PRISMA guidelines. A comprehensive search was performed on April 9, 2025, across databases including PubMed, Web of Science, Cochrane, IEEE, and Scopus to identify observational studies (cross-sectional or case–control) that utilized 3D or 4D scanning techniques for postural assessment in adults, with or without spinal deformities. Five of the studies included, which used devices labeled as “4D” but functioning in a static mode, were pooled for meta-analysis. Study quality was assessed using the Joanna Briggs Institute checklist, with a double-blind review process implemented to reduce the risk of bias. Thirteen studies met the inclusion criteria. The majority (n = 10) used 3D or 4D scanners for measuring posture in standing (n = 9) or sitting (n = 1) positions. Eight articles used the DIERS Formetric 4D device. Two studies focused on lumbar pelvic alignment, and one on the size and shape of the human physique. Closer examination revealed that assessments labeled as 4D were based not on full body 4D surface topography for the assessment of spinal curvature and body posture. The review concludes that current 3D scanning technologies are effective in analyzing human posture. While 4D full body scanning is promising and non-invasive, further research is necessary to fully explore its potential.