En-bloc retrograde resection of an osteoid osteoma of the patella using computed tomography under arthroscopic control.

Periarticular osteoid osteoma of the knee is a diagnostic and therapeutic challenge. This article presents a patient with a juxta-articular osteoid osteoma localized in the patella beneath the cartilage joint level and describes a simple and effective technique of arthroscopic computed tomography-guided en-bloc retrograde resection. The association of computed tomography and arthroscopy achieved a complete and minimally invasive removal of the lesion. This technique prevented damage to the proximal structures while permitting examination of the lesion and filling of the bony defect with the harvest removed from the proximal metaphysis of the tibia. Postoperative followup also was accomplished with arthroscopy and computed tomography.