TNF and intervertebral disk degenerative disorder: A large number of intracellular inflammatory factors such as IL-1β and tumor necrosis factor-α (TNF-α) has been found to be released outside the cell in the IDD, resulting in the high expression of MMP and a disintegrin and metalloproteinase with thrombospondin motifs (ADAMTS) enzymes in the ECM (Purmessur et al., 2013; Vo Nam et al., 2013).