Granuloma formation associated with patellar tendon necrosis in response to Ethibond confirmed by histopathological examination.

The aim of this study is to describe a case of delayed granuloma formation associated with tendon necrosis in response to Ethibond confirmed by histopathological examination and to review and discuss the related literature. A 40-year-old woman underwent a patellar tendon repair with Krakow-like #5 Ethibond sutures. Four years after the repair, she noticed progressive soreness with knee extension and swelling. An ultrasound examination revealed a proximal partial patellar tendon rupture. Based on these findings, the patient was advised to undergo surgical intervention due to a diagnosis of re-rupture. Tendinosis, fibrosis and necrosis scar tissue surrounding the previous suture were observed and excised, and samples were sent for histopathological and microbiological examination. Stripping of the patellar paratenon was performed. Surprisingly, a giant cell foreign body reaction surrounding the synthetic refringent material, as well as polymorphonuclear cells surrounding the necrotic tendon, was reported.