Exploring Lumbar Spine Posture and Movement in Sitting: A Comparison Between Laboratory and Real-World Measures

Mansour Abdullah Alshehri; Ryan Riddick; BESOMI MOLINA, MANUELA; Wolbert van den Hoorn; David M. Klyne; Paul W. Hodges

doi:10.3390/jcm14217518

Exploring Lumbar Spine Posture and Movement in Sitting: A Comparison Between Laboratory and Real-World Measures

Journal

Journal of Clinical Medicine

ISSN

2077-0383

Date Issued

2025-10-23

Author(s)

Mansour Abdullah Alshehri

Ryan Riddick

BESOMI MOLINA, MANUELA

Facultad de Medicina Clínica Alemana Universidad del Desarrollo

Wolbert van den Hoorn

David M. Klyne

Paul W. Hodges

Type

journal-article

DOI

10.3390/jcm14217518

URL

https://hdl.handle.net/123456789/11712

URL Institutional Repository

https://hdl.handle.net/11447/10963

Abstract

Background/Objectives: Sitting is linked to health problems, including back pain. Sitting posture is commonly measured in the laboratory, but it remains unclear how this relates to real-world spine posture. Methods: A cross-sectional study of pain-free adults conducted measurements in “laboratory” and “real-world” settings. Wearable motion sensors recorded lumbar spine angular orientation to compare lumbar spine flexion angle during sitting postures in between settings. Gaussian mixture models defined participant-specific modes and overall probability distributions of real-world sitting posture. Measures included periods of real-world sedentary/activity behaviours and trunk postural control (laboratory). Results: Laboratory measures of lumbar angle were more flexed during questionnaire (30.0°) than upright (19.8°) sitting. The angle in unstable sitting was intermediate (27.1°). Spine posture in unstable sitting correlated with real-world overall mean posture (r = 0.49–0.54) and most frequent mode (r = 0.47). Upright laboratory sitting posture correlated with real-world second most frequent mode (r = 0.54). Sitting less (r = 0.45) and walking more (r = 0.41) in the real world related to better balance performance and lumbar spine coordination. Conclusions: Spine posture in an unstable sitting laboratory task had the closest association with real-world sitting but does not replicate the diversity of spine postures adopted in real-world sitting. Wearable sensors are viable to study real-world postures.