Dysfunctional Microcirculation of the Lumbar Vertebral Marrow Prior to the Bone Loss and Intervertebral Discal Degeneration

STUDY DESIGN Descriptive study, stratified sampling. OBJECTIVE Using dynamic computed tomographic perfusion (CTP) to explore the age-related distribution patterns of the microcirculation perfusion in the vertebral marrow, the vertebral bone mineral density (BMD), and the intervertebral discal degeneration (IDD) further to discuss the possible causation between them. SUMMARY OF BACKGROUND DATA A latest viewpoint deemed that reduced blood supply of the vertebral marrow was correlated with an increased incidence of IDD and loss of BMD. However, the causative relationship between them needs more investigation. METHODS One hundred eighty-six general people were randomly enrolled by stratified sampling and grouped by age: 15 years or less, 16 to 25 years, 26 to 35 years, 36 to 45 years, 46 to 55 years, 56 to 65 years, 66 to 75 years, and 76 years or more. Both CTP and BMD of the third and fourth lumbar vertebral marrow were measured, and the IDD incidence of the third-fourth vertebrae was assessed. The temporal-spatial distribution patterns of the age-related changes of CTP, BMD, and IDD were described, and the correlations between them were calculated. RESULTS Microcirculatory perfusion of the vertebral marrow developed to maturate by 25 years, maintained stable at 35 years, and then declined by age after 35 years. BMD grew to a peak phase in 26 to 45 years and then dropped by years. However, IDD presented a sudden increase after 45 years of age. CTP (blood flow [r=0.806], blood volume [r=0.685], and permeability [r=0.619]) showed strong positive correlations and CTP (time to peak [r=-0.211], mean transit time [r=-0.598]) showed negative correlations with BMD. Meanwhile, CTP (blood flow [r=-0.815], blood volume [r=-0.753], and permeability [r=-0.690]) had strong negative correlations and CTP (time to peak [r=0.323] and mean transit time [r=0.628]) had positive correlations with the incidence of IDD. CONCLUSION Aging-related decrease of the microcirculatory perfusion of the lumbar vertebral marrow preceded the loss of BMD and the onset of IDD, indicating their possible causal relationship. LEVEL OF EVIDENCE 3.