What are bone islands in the knee?
A bone island in the knee, also known as enostosis, is a rarely symptomatic, benign chunk of dense bone inside softer, spongy bone.DiagnosisBone islands may be found incidentally on digital images taken for different reasons. According to a 1995 study by the radiology department at the University of California, Davis, School of Medicine, despite a tumor-like appearance, bone islands are not cancerous and typically painless.LocationThe UC Davis study indicated that bone islands–most commonly found in the pelvis, spine, ribs and in the long bones of the arms and legs–can develop in the knees as well.OccurrenceAccording to eMedicine, the reported frequency of bone islands ranges from 1 percent to 14 percent. Equally common in either gender, regardless of race, adults are more likely to have an enostosis diagnosis.TreatmentBone islands rarely cause symptoms or pain, making treatment unnecessary.
