Heterogeneity in microstructural deterioration following spinal cord injury

Modelling and remodelling adapt bone morphology to accommodate strains commonly encountered during loading. If exceed a threshold threatening fracture, modelling-based formation increases volume reducing these strains. unloading reduces below that inhibits resorption, increased remodelling-based resorption restoring strains, but at the price of compromised microstructure. As weight-bearing regions are adapted greater we hypothesized microstructural deterioration will be more severe than low following spinal cord injury. We quantified distal tibial, fibula radius volumetric mineral density (vBMD) using high-resolution peripheral quantitative computed tomography in 31 men, mean age 43.5 years (range 23.5?75.0), 12 with tetraplegia 19 paraplegia 0.7 18.6 duration, 102 healthy age- sex-matched controls. Differences relative controls were expressed as standardized deviation (SD) scores (mean ± SD). Standardized between-region differences vBMD SDs (95% confidence intervals, CI). Relative controls, men had deficits total ?1.72 1.38 SD tibia (p < 0.001) ? 0.68 0.69 = 0.041), not radius, despite paralysis. Deficits ?2.14 1.50 ?0.83 0.98 0.005) while radial was 0.23 1.02 0.371), significantly increased, upper limb mobility. Comparing regions, tetraplegia, tibial 1.04 (95%CI 0.07, 2.01) lower 0.037) 1.51 0.45, 2.57) 0.007); latter two sites did differ from each other. Results similar paraplegia, 1.06 0.35, 1.77) 0.004). Microarchitectural injury is heterogeneous, perhaps partly because strain thresholds regulating cellular activity mechano-transduction region specific.