Immune responses to low back pain risk factors.

$\underline{Objective}$: Investigate effects of interactions between biomechanical, psychosocial and individual risk factors on the body's immune inflammatory responses. $\underline{Background}$: Current theories for low back pain causation do not fully account for the body's response to tissue loading and tissue trauma. $\underline{Methods}$: Two groups possessing a preference for the sensor or intuitor personality trait performed repetitive lifting combined with high or low mental workload on separate occasions. Spinal loading was assessed using an EMG-assisted subject-specific biomechanical model and immune markers were collected before and after exposure. $\underline{Results}$: Mental workload was associated with a small decrease in AP shear. Both conditions were characterized by a regulated time-dependent immune response making use of markers of inflammation, tissue trauma and muscle damage. Intuitors' creatine kinase levels were increased following low mental workload compared to that observed in Sensors with the opposite trend occurring for high mental workload. $\underline{Conclusions}$: A temporally regulated immune response to lifting combined with mental workload exists. This response is influenced by personality and mental workload.