Abstract
We reported a recent case of osteonecrosis of the patella that required multiple operations. A 44-year-old man underwent arthroscopic partial medial meniscectomy and the resection of osteochondroma of left knee. He complained of left anterior knee pain during rehabilitation, which was diagnosed as osteonecrosis of the patella. He underwent arthroscopic drilling of the patella 3 months after the first operation, but his complaints had not been improved. Then he underwent the combined procedure of both mosaicplasty and the anterior displacement of the tibial tuberosity 10 months after the second operation. Sixteen months after the third operation, his symptoms were improved. We supposed that in cases of osteochondral lesion not only treatment for the lesion itself, but also removal of the cause should be required.