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Updated: Jul 15, 2026
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Modified Posterior Vertebral Column Resection for Patients with Thoracolumbar Kyphotic Deformity
Published on: September 16, 2022
Thoracic kyphosis affects spinal loads and trunk muscle force
Andrew M Briggs1, Jaap H van Dieën, Tim V Wrigley
1Department of Epidemiology and Preventive Medicine, Monash University, Australia. abriggs@cabrini.com.au
Physical Therapy
|May 3, 2007
Summary
Increased thoracic kyphosis significantly elevates spinal loads and trunk muscle forces. This biomechanical evidence suggests a link between heightened spinal loading and accelerated degeneration, pain, and dysfunction.
Area of Science:
- Biomechanical analysis of spinal disorders.
- Orthopedic biomechanics and posture.
Background:
- Increased thoracic curvature (kyphosis) is a common concern for physical therapy patients.
- Current treatments lack substantiated biomechanical rationales for managing kyphosis.
Purpose of the Study:
- To investigate the biomechanical effects of increased thoracic kyphosis.
- To provide evidence for the relationship between thoracic curvature and spinal loading.
Main Methods:
- Compared high kyphosis and low kyphosis groups (n=44).
- Utilized lateral radiographs and photographs digitized for biomechanical modeling.
- Estimated net segmental loading and trunk muscle forces from T2-L5.
Main Results:
- High kyphosis group showed significantly greater flexion moments, compression, and shear forces.
- Trunk muscle forces were also significantly higher in the high kyphosis group.
- Strong correlations found between thoracic curvature and spinal loads (r=0.85–0.93) and muscle forces (r=0.70–0.82).
Conclusions:
- Elevated thoracic kyphosis is associated with increased multisegmental spinal loads and trunk muscle forces.
- These biomechanical factors likely accelerate spinal degeneration.
- Increased loads may contribute to spinal dysfunction and pain development.
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