Correlation Analysis between Leg-length Discrepancy and Lumbar Scoliosis Using Full-length Standing Radiographs.

Area of Science:

• Orthopedics
• Radiology
• Biomechanical analysis

Background:

• Leg-length discrepancy (LLD) can lead to secondary postural issues like lumbar scoliosis.
• Previous research has not definitively linked LLD to lumbar curvature using comprehensive radiographic data.

Purpose of the Study:

• To investigate the correlation between leg-length discrepancy (LLD) and lateral lumbar spine curvature.
• To utilize full-length standing radiographs of lower limbs and the spine for analysis.

Main Methods:

• Reviewed standing radiographs of 113 participants (ages 10-65).
• Measured leg length and calculated LLD (mm) and LLD ratio (LLDR).
• Assessed lumbar lateral curvature using the Cobb angle and analyzed correlations with LLD and LLDR via regression analysis.

Main Results:

• A strong positive correlation was found between LLD and lumbar Cobb angle (γ = 0.53).
• A strong positive correlation was also observed between LLDR and lumbar Cobb angle (γ = 0.62).
• Regression equations established quantitative relationships between LLD/LLDR and lumbar Cobb angle.

Conclusions:

• Objective imaging data confirms a tendency for lumbar Cobb angle >10° when leg-length discrepancy exceeds 20 mm.
• This study provides evidence for the association between LLD and lumbar scoliosis.