Osteoporos Int, 2018 · DOI: 10.1007/s00198-018-4733-0 · Published: December 1, 2018
Spinal cord injury (SCI) leads to significant bone loss, especially around the knee, increasing the risk of fractures. This study used CT scans and finite element (FE) models to analyze bone stiffness and mineral content in the distal femur and proximal tibia of individuals with SCI over a period of 0-50 years post-injury. The study found that bone degradation occurs rapidly after SCI, reaching a stable state within 3.5 years. During this time, bone stiffness can decrease by 40% to 85%, and bone mineral content also significantly reduces, compared to individuals shortly after their injury. Importantly, standard CT scans may underestimate the extent of bone weakening compared to FE models, which assess mechanical stiffness directly. The findings suggest that interventions to prevent bone loss should be implemented early after SCI to maximize effectiveness.
Pharmaceutical interventions to reduce fracture risk after SCI may be most effective if administered soon after injury, before bone loss becomes critical.
CT derived measures of bone mineral alone tend to underestimate the mechanical consequences of bone loss, suggesting the need for more comprehensive assessment methods like FE modeling.
The similar magnitude and rate of stiffness loss between the tibia and femur suggests that treatment strategies can target both bones equally.