MMP3 and Pain: Figure 5 showed the predicted results of this final SVM model for Set 1 patients, 32/36 patients actually had CPSP when they were predicted to have CPSP, while 25/27 patients without CPSP were predicted to not develop CPSP. Matrix metalloproteinases (MMPs) have been implicated in the modulation of synaptic plasticity, glial activation, and long-term potentiation in the CNS and MMP3 was proved to regulate of nociceptive processing in thermal hyperalgesia and tactile hypersensitivity (19), which was consistent with the ID pain result above that most CPSP associated with neuropathic pain.