MRI of the knee is commonly used to diagnose and evaluate various conditions affecting the knee joint, such as:
1. **Ligament Injuries**: Including tears of the ACL (anterior cruciate ligament), PCL (posterior cruciate ligament), MCL (medial collateral ligament), and LCL (lateral collateral ligament).
2. **Meniscus Tears**: Detecting tears in the meniscus, which are common in athletes or due to degeneration.
3. **Cartilage Damage**: Evaluating the articular cartilage for wear, tears, or defects.
4. **Bone Fractures**: Detecting subtle bone fractures that may not be visible on X-rays.
5. **Tendon Injuries**: Including tears or inflammation of the tendons, such as the patellar tendon or quadriceps tendon.
6. **Baker's Cyst**: Visualizing fluid-filled cysts in the back of the knee.
7. **Osteoarthritis**: Assessing the severity of joint degeneration and cartilage loss.
8. **Tumors and Infections**: Identifying abnormal masses or signs of infection in the knee joint or surrounding tissues.
It is often used when there is persistent knee pain, swelling, or instability that has not been clearly diagnosed with other imaging methods.