Hyperpigmented concentric rings over the tibia are secondary to prior inflammation. Residual hemosiderin from broken down red blood cells in macrophages, left behind after inlammation pigments the skin.
Review Date 4/16/2019
Updated by: Michael Lehrer, MD, Clinical Associate Professor, Department of Dermatology, University of Pennsylvania Medical Center, Philadelphia, PA. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.