Patelar metastasis of primary lung cancer

Patellar metastasis is uncommon. The clinical presentation is often misleading, suggestive of septic arthritis or meniscal disorder after knee trauma. We report the case of a 71-year-old patient who developed knee pain aggravated by movement with pseudo-blockage which was found to be related to a secondary localization of a primary lung cancer. Low blood flow in the patella probably explains why patellar metastasis is so rare.