IA steroid injections into the epidural space reduce inflammation by inhibiting the release of pro-inflammatory cytokines and chemokines, while inhibiting the production of cyclooxygenase-2 (COX-2) and prostaglandins (PGE2), while also decreasing matrix metalloproteinase (MMP) synthesis, thus alleviating pain, swelling, radiculopathy, and improving nerve function [51, 89]. This evidence concerns the gene PTGS2 and radiculopathy.