Knee pain is a common condition that can affect people of all ages. It may be caused by acute injuries (such as ligament tears, meniscus injuries, or fractures), chronic conditions (like osteoarthritis, rheumatoid arthritis, or bursitis), or overuse (as seen in tendinitis or runner’s knee). The pain may be localized to the front, side, or back of the knee and can be accompanied by swelling, stiffness, instability, or reduced range of motion. Diagnosis typically includes a physical examination, imaging tests such as X-rays or MRI, and sometimes lab work if infection or inflammation is suspected. Treatment depends on the underlying cause and may involve rest, medication, physical therapy, bracing, or surgical intervention.