Complex Regional Pain Syndrome (CRPS) is a chronic pain condition that typically affects one limb (arm, leg, hand, or foot) often after an injury, surgery, or trauma to that limb. CRPS is characterized by severe, persistent pain that is disproportionate to the severity of the initial injury.

Causes of CRPS:

• Injury or Trauma: The condition often develops after a significant injury to a limb, such as fractures, sprains, or surgeries.

• Nerve Damage: CRPS may occur when the injury involves nerve injuries, though the exact mechanism isn't always clear.

• Abnormal Inflammatory Response: The body's response to the injury can be excessive or abnormal, leading to prolonged or excessive pain.

• Dysfunction in the Central or Peripheral Nervous Systems: Abnormal signaling in the nerves can lead to pain that persists long after the original injury has healed.

Impact on Life: CRPS can drastically affect a person's quality of life. The constant, severe pain can limit mobility and function of the affected limb, leading to difficulty in performing daily tasks and maintaining employment. Moreover, the persistent pain and physical limitations can lead to psychological issues, including depression, anxiety, and social isolation. This type of condition can be treated by sympathetic nerve blocks, peripheral nerve stimulation, and ketamine infusions.