A moderate spinal contusion injury in rats alters bone turnover both below and above the level of injury with sex-based differences apparent in long-term recovery

Spinal cord injury (SCI) leads to significant bone loss, especially in the lower limbs, increasing the risk of fractures. This study investigates whether bone loss also occurs above the level of injury, suggesting systemic factors are at play. The research examines bone microarchitecture and turnover in the supralesional humerus of rats with moderate contusion SCI at both sub-chronic (30 days) and chronic (180 days) time points after injury, comparing male and female rats. The study reveals that SCI affects bone turnover above the injury level within 30 days, with male rats showing lower bone formation rates in the supralesional humerus even in long-term recovery, indicating systemic factors contribute to bone loss after SCI.

• 1
  Young male rats showed reduced trabecular bone volume at both the sublesional tibia and supralesional humerus following SCI.
• 2
  Adult male rats exhibited lower supralesional trabecular bone volume at 30 days post-injury.
• 3
  At 30 days post-injury, all SCI rats displayed lower bone formation rates and higher osteoclast-covered trabecular surfaces in the proximal humerus compared to age-matched sham groups.