Pain starts from activation of the nervous system. There are 9 steps of the pain circle:
Step 1: Local inflammation. Anything causing tissue damage such as injury, surgery, or infection can lead to local inflammation. This is the origin of the pain.
Step2: Peripheral sensitization. Local inflammation irritates the nerves lowering the pain threshold causing peripheral sensitization.
Step3: Central sensitization. Nerve signals are transmitted to the brain causing central sensitization.
Step4: Pain sensation. The brain tells you that there is pain in the body somewhere.
Step5: Pain cognitive processes. The brain where is sensing the pain connects other part of the brain where controls emotion causing emotional and behaviour changes.
Step6: Depression and anxiety. The brain where controls emotions is affected by the pain signals and alters its function causing depression and anxiety
Step7: Cortical reorganization. The brain reallocates its task to different parts of the body to reduce pain sensation and help replace the lost function.
Step8: Avoidance and disability. The body will respond the brain demands to redistribute the work causing avoidance and disabililty.
Step9: Muscle spasm deconditioning. Injured and related muscles become spasmed to protect the body from moving and feeling the pain causing muscle waste.
