Correlation between Pathological Characteristics and Young’s Modulus Value of Spastic Gastrocnemius in a Spinal Cord Injury Rat Model

This study explores the relationship between muscle stiffness and muscle characteristics in rats with spinal cord injuries. The researchers aimed to understand how spinal cord injury affects muscle stiffness by examining the gastrocnemius muscle (GM) tissue. Rats were divided into groups with and without spinal cord injuries, and the stiffness of their GM was measured using shear wave sonoelastography. Pathological examinations were also performed to analyze the muscle tissue. The findings showed that spinal cord injury led to changes in muscle fiber types and increased muscle stiffness. The stiffness was negatively correlated with the proportion of type I muscle fibers, suggesting a link between muscle composition and stiffness after spinal cord injury.

• 1
  GM weights were decreased in the SCI model group compared to the control group, indicating muscle atrophy.
• 2
  The ratio of type I fibers was decreased, while the ratio of type II fibers was increased in the GM of the SCI model group.
• 3
  A significant negative correlation was found between Young’s modulus value of GM and the ratio of type I fibers of GM in the SCI model subgroup, suggesting that lower type I fiber ratios are associated with increased stiffness.