G90.529 ICD-10-CM Code: Complex regional pain syndrome I of unspecified lower limb

G90.529 is the ICD-10-CM diagnosis code for complex regional pain syndrome i of unspecified lower limb. Complex regional pain syndrome type I is a chronic pain condition affecting the lower limb (leg or foot) that develops after an injury, surgery, or other triggering event, characterized by pain, swelling, and changes in skin color or temperature. The 'unspecified' designation means the documentation does not identify which specific lower limb (left or right) is affected. G90.529 sits in the ICD-10-CM chapter for diseases of the nervous system (g00-g99), within the section covering other disorders of the nervous system (g89-g99).

G90.529 is a billable ICD-10-CM code but does not map to a payment HCC under the CMS-HCC V28, V24, ESRD, or RxHCC risk adjustment models. It can be reported on Medicare Advantage encounter data submissions but it does not contribute to a beneficiary's RAF score and therefore does not affect risk-adjusted payments to the plan.

Verify documentation specifies CRPS type I (not type II) and confirm the lower limb location; if laterality is documented, use the more specific code G90.521 (left) or G90.522 (right) instead of unspecified.