Michael Pagliaro, left, laughs with Paul Scattaretico at the Muzic Store Inc. in Dobbs Ferry, N.Y., as Pagliaro picks up instruments for his rental business. Before Pagliaro had a hip replacement, pain made it difficult to work. Maggie Starbard/NPR hide caption

itoggle caption Maggie Starbard/NPR

Young-min Kwon of Massachusetts General Hospital holds the metal-alloy ball of Susy Mansfield's faulty artificial hip joint. The yellowish tissue on top is dead muscle caused by a reaction to the metal debris produced by the defective hip implant. Richard Knox/NPR hide caption

itoggle caption Richard Knox/NPR