What is Complex Regional Pain Syndrome (CRPS)?

Complex Regional Pain Syndrome (CRPS) is a chronic pain condition typically affecting a limb after injury, surgery, stroke, or heart attack, characterized by severe, persistent pain that is disproportionate to the initial cause (Marinus et al., 2011). The pain is often described as burning, shooting, or throbbing, and is accompanied by sensory, motor, autonomic, and trophic changes such as swelling, skin color changes, temperature asymmetry, sweating abnormalities, and decreased mobility (Bruehl, 2015). CRPS is divided into two types: Type I, where no nerve injury is identified, and Type II, which involves confirmed nerve damage.

Treatment Approaches

Management of CRPS requires a multidisciplinary approach, including:

Physical therapy

To maintain limb function and reduce stiffness.

Pharmacological treatments

Such as analgesics, corticosteroids, bisphosphonates, anticonvulsants, and sometimes opioids.

Interventional therapies

Sympathetic nerve blocks, spinal cord stimulation, or ketamine infusions may be used in refractory cases.

Ketamine Use in CRPS

Ketamine, an NMDA receptor antagonist, has been studied extensively for CRPS treatment due to its ability to inhibit central sensitization and reduce neuropathic pain. Ketamine infusions can provide significant pain relief and improve function in many CRPS patients, although responses vary, and repeated treatments might be necessary.