Analysis of compressive load on intervertebral joint in standing and sitting postures.
BACKGROUND
There have been some disagreements on the comparison of disc pressures in the standing and sitting postures in literature. Most research on in vivo pressure needle measurement found higher disc pressure in sitting than in standing. The disc pressure data can help to advocate better postures for clinical advice.


OBJECTIVE
The aim of this paper is to develop a procedure to study the compressive load on intervertebral joint in the standing and sitting postures through the approach of motion capture and musculoskeletal modeling.


METHODS
The marker data of six subjects performing various standing and sitting postures was obtained during the motion capture experiment and used to train the musculoskeletal model with an enhanced discretized spine developed for subject in the inverse and forward simulations.


RESULTS
Compressive loads on L3-L4 and L4-L5 joints are found higher in upright sitting than in upright standing. Slumped sitting, cross-legged sitting and flexion sitting can introduce higher compressive loads on intervertebral joints compared with upright sitting.


CONCLUSIONS
These findings indicate the effects of standing and sitting postures on the spinal joint loads. The results can provide doctors and therapists with more information on clinical advice on better postures for people with spinal problems.
College of Mechanical and Electronic Engineering, China University of Petroleum, Qingdao, Shandong, China.
Mengjie
M
Huang
Department of Mechanical Engineering, National University of Singapore, Singapore.
Khatereh
K
Hajizadeh
School of Engineering, Deakin University, Geelong Waurn Ponds, Victoria, Australia.
Ian
I
Gibson
Department of Medical Biotechnology, Dongguk University, Seoul, Korea.
Taeyong
T
Lee
D000328:Adult; D001696:Biomechanical Phenomena / Q000502:physiology*; D005260:Female; D006801:Humans; D007596:Joints; D008159:Lumbar Vertebrae / Q000502:physiology*; D008297:Male; D011187:Posture / Q000502:physiology*
Compressive load; intervertebral joint; musculoskeletal modeling; sitting; standing