Conditioned Pain Modulation Decreases Over Time in Patients With Neuropathic Pain Following a Spinal Cord Injury

This study investigates how the body's pain modulation system changes over time in individuals with spinal cord injury (SCI) who experience neuropathic pain. The researchers aimed to understand if problems with this system contribute to the development of chronic pain after SCI. The study involved assessing patients with SCI at two points: shortly after their injury (admission to rehab) and later during their rehab stay (discharge). They measured how well the patients' bodies could inhibit pain using a test called conditioned pain modulation (CPM). The findings suggest that having neuropathic pain after SCI leads to a decrease in the body's ability to modulate pain over time. This indicates that the pain itself might be affecting the pain modulation system, rather than the other way around.

• 1
  A significant decrease in the efficacy of conditioned pain modulation (CPM) was observed over time in patients with SCI.
• 2
  The decrease in CPM efficacy was observed only in patients already suffering from neuropathic pain at admission.
• 3
  Higher levels of neuropathic pain at admission were associated with more effective CPM initially, suggesting a possible initial boosting of antinociceptive functions.