or surrounding tissues become damaged.

Some conditions develop gradually.

Others can progress much more quickly.

What Is the Abnormal Area Shown in the Image?

The large irregular region shown on the right side appears to represent destructive abnormal tissue involving bone.

Images like this are sometimes used to illustrate serious bone lesions, including tumors.

However, an important distinction is necessary:

A picture alone cannot establish a diagnosis.

A real patient with an abnormal area inside or around the knee would require a medical history, physical examination, and usually imaging such

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