Causalgia of unspecified upper limb

This code represents causalgia, a severe, burning pain syndrome, affecting an unspecified part of the upper limb. It is characterized by allodynia and hyperalgesia, often accompanied by vasomotor and sudomotor dysfunction. This condition is typically a consequence of nerve injury.

Use this code when the patient presents with symptoms consistent with causalgia in the upper limb, but the specific side (left or right) is not documented. This code is appropriate when the physician's documentation clearly states "causalgia of upper limb" without further laterality.

• Do not use this code if laterality (left or right) is specified; instead, use G56.41 or G56.42.
• Ensure documentation supports a diagnosis of causalgia, not just general neuropathic pain.
• Consider sequencing this code after a code for the underlying nerve injury, if known and documented.