E-ISSN: 1019-5157
ISSN: 2651-5024
Research
Biomechanical Evaluation of Exoskeleton Systems for the Prevention of Lumbar Spine Injuries in Military Personnel: A Finite Element Analysis
Salih Batuhan Kartal ,
Idris Avci✉ ,
Ahmed Yasin Yavuz ,
Selim Şeker
Neurosurgery, Bilge Hospital, Department Of Neurosurgery, Sakarya, Turkey; Neurosurgery, Acıbadem Kadıköy Hospital, Istanbul, Turkey; Neurosurgery, Prof. Dr. Cemil Tascioglu City Hospital; Neurosurgery, Istinye University Hospital, Istanbul, Turkey
Accepted: 08/09/2026
Article in Press
Corresponding Author:
Idris Avci (dr.idrisavci@gmail.com)
Abstract
Aim
To quantify the effects of a passive exoskeleton on lumbar compressive forces, intradiscal pressure, and stress distribution during simulated military load carriage.
Material and Methods
A three-dimensional finite element (FE) model of the L1–S1 spine was reconstructed from recumbent computed-tomography data from one healthy 30-year-old male. A static 400 N vertical load was applied to the superior endplate of L3. Two deterministic conditions were compared: load carriage without assistance and an idealised passive exoskeleton condition in which 27.5% of the applied axial load was predefined to follow an external pathway toward the pelvis. Sensitivity analyses varied load sharing, support stiffness, pelvic-interface stiffness, external load, loading direction, and device configuration. No inferential statistical testing was performed.
Results
In the baseline model, L4–L5 compressive force decreased from 4200 N to 3100 N (26%), and L5–S1 intradiscal pressure decreased from 1.9 MPa to 1.3 MPa (32%) in the exoskeleton-assisted condition. Peak posterior-element stress decreased from 6.00 MPa to 4.05 MPa. In the sensitivity dataset, prescribed load sharing and external-load magnitude had the largest influence, whereas changing the support-member modulus from 50 to 70 GPa produced comparatively small changes.
Conclusion
The model demonstrates an idealised passive exoskeleton reduced lower-lumbar compressive forces, intradiscal pressure, and posterior-element stress by redistributing part of the carried load toward the pelvis. These findings provide quantitative biomechanical targets for device optimisation and support further experimental and dynamic evaluation of passive exoskeletons as a potential strategy for reducing lumbar mechanical burden during military load carriage.
To quantify the effects of a passive exoskeleton on lumbar compressive forces, intradiscal pressure, and stress distribution during simulated military load carriage.
Material and Methods
A three-dimensional finite element (FE) model of the L1–S1 spine was reconstructed from recumbent computed-tomography data from one healthy 30-year-old male. A static 400 N vertical load was applied to the superior endplate of L3. Two deterministic conditions were compared: load carriage without assistance and an idealised passive exoskeleton condition in which 27.5% of the applied axial load was predefined to follow an external pathway toward the pelvis. Sensitivity analyses varied load sharing, support stiffness, pelvic-interface stiffness, external load, loading direction, and device configuration. No inferential statistical testing was performed.
Results
In the baseline model, L4–L5 compressive force decreased from 4200 N to 3100 N (26%), and L5–S1 intradiscal pressure decreased from 1.9 MPa to 1.3 MPa (32%) in the exoskeleton-assisted condition. Peak posterior-element stress decreased from 6.00 MPa to 4.05 MPa. In the sensitivity dataset, prescribed load sharing and external-load magnitude had the largest influence, whereas changing the support-member modulus from 50 to 70 GPa produced comparatively small changes.
Conclusion
The model demonstrates an idealised passive exoskeleton reduced lower-lumbar compressive forces, intradiscal pressure, and posterior-element stress by redistributing part of the carried load toward the pelvis. These findings provide quantitative biomechanical targets for device optimisation and support further experimental and dynamic evaluation of passive exoskeletons as a potential strategy for reducing lumbar mechanical burden during military load carriage.
Keywords
exoskeleton
lumbar spine biomechanics
load carriage
finite element analysis
millitary medicine