301: Effect of load carriage on spinal alignment in individuals with chronic low back pain

Topic: Clinical Science
Subtopic: Pain category (ICD-11), Chronic primary musculoskeletal pain, Developing methodology/technology, Digital Health Technologies

Background and Aims: External load carriage is a common daily activity that places substantial mechanical demands on the spine. The objectives of this study were to examine the effects of external load on sagittal spinal alignment in patients with CLBP and to identify predictors of load-induced morphological changes.

Methods: This cross-sectional, within-subject study included 62 males with mild–to–moderate CLBP (>3 months). The intensity of back pain and functional disability were measured using the visual analog scale and the Oswestry Disability Index. The spinal parameters were assessed using the DIERS Formetric 4D system during quiet standing and while holding a 10-kg anterior load. The primary outcome was the change in lumbar lordosis (ΔLL). Secondary outcomes included changes in global sagittal spinal angle, thoracic kyphosis, flèche lombaire, and flèche cervicale. Paired t-tests, Pearson correlations, and hierarchical regression analyses were performed.

Results: Load carriage significantly increased thoracic kyphosis (mean difference 2.22°, p = 0.002) and flèche lombaire, while reducing the global sagittal spinal angle. Lumbar lordosis showed a small, non-significant increase in the overall cohort. In age-stratified analyses, older adults (>60 years) demonstrated significant load-induced changes in lumbar lordosis and global sagittal alignment compared with younger adults (<60 years). Hierarchical regression analysis identified pain intensity as the strongest predictor of load-induced change in lumbar lordosis (β = 0.599, p < 0.001), followed by age, with the final model explaining 55% of the variance.

Conclusions: Individuals with CLBP demonstrate characteristic sagittal realignment under load, primarily driven by pain severity. These findings highlight pain-mediated motor adaptations and support reconsideration of load-handling guidelines and rehabilitation strategies for CLBP.

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Presenting Author: Apurba Barman
Submitting Author: Apurba Barman

Senior Author: Apurba Barman

IASP 2026 Global Year theme of Neuropathic Pain: No

• Swarupananda Mandal: MD - All India Institute of Medical Sciences (AIIMS), Bhubaneswar
• Suman Patel: MD - All India Institute of Medical Sciences (AIIMS), Bhubaneswar