Images of the Knee

Gallery of Images, Photos, and X-Rays of the Knee

The knee is the largest joint in the body. A hinge joint, the knee is made up of three bones, two different types of cartilage, and four ligaments. The many structures of the knee make the joint vulnerable to injuries.

Knee injuries are commonly diagnosed using X-rays or magnetic resonance imaging (MRI) tests.

This article contains pictures of the knee joint, including X-rays, diagrams, and real images of knee injuries.


Bones of the Knee

lower extremity
Science Picture Co / Getty Images

The knee joint contains three bones. The femur (thigh bone) and tibia (shin bone) meet at the knee joint. The patella (kneecap) sits in front of it. 

Common bone injuries in the knee joint include fractures and dislocations.


Knee X-Ray: Anteroposterior (AP) View

Image © Jonathan Cluett, MD

An X-ray is one of the most common imaging tests used to diagnose knee problems. X-rays are used to show bones and joint spacing. Fractures, dislocations, subluxations, and signs of arthritis can be seen on X-rays.

The image here is a front-to-back view of a healthy knee joint. This is also known as the anteroposterior (AP) view. 


Knee X-Ray: Lateral View

Image © Medical Multimedia Group

While an AP X-ray looks from front-to-back of the knee joint, a lateral view looks at the joint from the side. 

Lateral X-rays are particularly helpful at seeing the kneecap, or patella, and the cartilage space behind the kneecap.


Articular and Meniscus Cartilage


The knee bones are lined with a smooth cover known as articular cartilage. This slippery substance that help the bones glide as the joint moves.

Two wedge-shaped piece of meniscus cartilage sit between the articular cartilage of the femur and tibia. The meniscus acts like a shock absorbers.

Meniscal tears are a common sports injury, but can also be caused by arthritis or aging.

When people talk about knee cartilage, they may be talking about either the meniscus cartilage or the articular cartilage.


Anterior Cruciate Ligament

knee anatomy
Jeannot Olivet / Getty Images

Four ligaments act as strong ropes to keep the knee stable:

  • The medial (inside) and lateral (outside) collateral ligaments control side-to-side movements.
  • The anterior (front) and posterior (rear) cruciate ligaments control front-to-back motions.

In this image, the practitioner points to the anterior cruciate ligament (ACL).

ACL tears are a common knee injury that occurs from quickly changing direction or landing from a jump incorrectly. ACL injuries are more common in soccer, football, and basketball and often involve damage to other structures in the knee.


Knee Arthritis

X-ray showing arthritic knees
Science Photo Library - DR P. MARAZZI/Brand X Pictures/Getty Images

Arthritis is a condition that causes pain and inflammation in joints.

Many different types of arthritis can occur in the knees, the most common of which is called osteoarthritis.

People often use the words "wear-and-tear" to describe osteoarthritis, as it occurs when the cartilage between joints wears away. This causes pain, stiffness, and trouble moving.


Knee Replacement

P. Marazzi / Getty Images

Knee replacement surgery is commonly used to treat pain and mobility issues caused by severe arthritis. 

During the procedure, damaged cartilage and bone are removed and replaced with a new implant, made of plastic or metal (or both), to restore the function of the knee.

6 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Harvard Health Publishing. X-ray may be best screening tool for diagnosing knee pain.

  2. American Academy of Orthopaedic Surgeons: OrthoInfo. Common knee injuries.

  3. Lee Y. C. (2013). Effect and treatment of chronic pain in inflammatory arthritis. Current rheumatology reports15(1), 300. doi: 10.1007/s11926-012-0300-4

  4. Centers for Disease Control and Prevention. Osteoarthritis (OA).

  5. Carr AJ, Robertsson O, Graves S, et al. Knee replacement. The Lancet. 2012;379(9823):1331-1340. doi: 10.1016/s0140-6736(11)60752-6

  6. The Cleveland Clinic. Total Knee Replacement Surgery.

Additional Reading

By Jonathan Cluett, MD
Jonathan Cluett, MD, is board-certified in orthopedic surgery. He served as assistant team physician to Chivas USA (Major League Soccer) and the United States men's and women's national soccer teams.