Childhood adversity such as neglect or abuse is associated with disease and disability later in life,85 causing higher Th17 cell numbers, a higher IL-6 response to stress, and autoimmune and inflammatory diseases.86 Depression and associated poor rehabilitation compliance are sometimes cited as causative factors for arthrofibrosis,7 however, it is interesting to note that depression is strongly associated with inflammation, and inflammation can cause depression.87,88 Therefore, it seems likely that the inflammatory processes associated with active arthrofibrosis cause depression. This evidence concerns the gene IL6 and major depressive disorder.