Why is an X-ray Knee AP/LAT/Merchant's View Performed?
An X-ray of the knee using AP, LAT, and Merchant's views is often recommended when a patient experiences knee pain, instability, or suspected injury. Common reasons for performing this procedure include:
1] Knee injuries: After trauma or injury, an X-ray is essential for detecting fractures, dislocations, or ligament damage.
2] Knee pain or swelling: Chronic knee pain or swelling can be caused by various conditions like arthritis, ligament damage, or cartilage tears, which can be assessed through these views.
3] Arthritis: Conditions like osteoarthritis or rheumatoid arthritis can lead to joint space narrowing, bone spurs, or cartilage degradation, which can be clearly visible in the AP, LAT, and Merchant's views.
4] Patellar problems: The Merchant’s view is particularly effective for diagnosing issues with the patella, such as patellar malalignment, patellofemoral pain syndrome, or cartilage wear.
5] Pre-surgical evaluation: For patients undergoing knee surgery, these views provide essential information for surgical planning, such as assessing joint alignment and determining the extent of cartilage or bone damage.
How is the X-ray Knee AP/LAT/Merchant's View Performed?
The procedure for an X-ray knee using the AP, LAT, and Merchant’s views is typically fast and non-invasive. Here’s how it’s usually performed:
1] AP View: The patient is asked to sit or lie down, and the knee is positioned straight. The X-ray machine is positioned in front of the knee, and the image is captured as the X-ray beam passes from the front to the back of the knee.
2] LAT View: For the lateral view, the patient will lie on their side, and the knee is bent at a 30 to 45-degree angle. The X-ray beam is directed from one side of the knee to the other. The technician will ensure that the knee is aligned properly for a clear image.
3] Merchant's View: In the Merchant’s view, the patient is asked to sit with the knee bent at approximately 45 degrees. The knee is held in position while the X-ray beam is directed from above at a 30-degree angle to visualize the patellofemoral joint clearly. This view provides a clear look at the kneecap and its alignment with the femur.
The entire process typically takes only a few minutes, and the patient may be asked to hold still and remain in position while the images are taken.
