Orthopedics Hip & Knee Images of the Knee Gallery of Images, Photos, and X-Rays of the Knee By Jonathan Cluett, MD Jonathan Cluett, MD LinkedIn Twitter Jonathan Cluett, MD, is a board-certified orthopedic surgeon with subspecialty training in sports medicine and arthroscopic surgery. Learn about our editorial process Updated on June 21, 2022 Medically reviewed Verywell Health articles are reviewed by board-certified physicians and healthcare professionals. These medical reviewers confirm the content is thorough and accurate, reflecting the latest evidence-based research. Content is reviewed before publication and upon substantial updates. Learn more. by Yaw Boachie-Adjei, MD Medically reviewed by Yaw Boachie-Adjei, MD LinkedIn Yaw Boachie-Adjei, MD, is a board-certified, double-fellowship Orthopedic Surgeon at Kaiser Permanente in Georgia. Learn about our Medical Expert Board Fact checked Verywell Health content is rigorously reviewed by a team of qualified and experienced fact checkers. Fact checkers review articles for factual accuracy, relevance, and timeliness. We rely on the most current and reputable sources, which are cited in the text and listed at the bottom of each article. Content is fact checked after it has been edited and before publication. Learn more. by Angela Underwood Fact checked by Angela Underwood LinkedIn Angela Underwood's extensive local, state, and federal healthcare and environmental news coverage includes 911 first-responder compensation policy to the Ciba-Geigy water contamination case in Toms River, NJ. Her additional health-related coverage includes death and dying, skin care, and autism spectrum disorder. Learn about our editorial process Print 1 The Knee Joint Jeannot Olivet / Getty Images The knee is one of the most commonly injured joints in the body. The knee joint is the junction of the thigh and the leg (part of the lower extremity). The femur (thigh bone) contacts the tibia (shin bone) at the knee joint. The patella (kneecap) sits over the front of the knee joint. Four major ligaments connect the bones and stabilize the knee joint. In the image above, the physician is pointing to the anterior cruciate ligament, or ACL, one of these important ligaments. Common Causes of Knee Pain 2 Inside the Joint SPRINGER MEDIZIN / Getty Images Inside the knee joint is a smooth cover on the ends of the bone called articular cartilage. Between the articular cartilage layer, is a shock absorbing cushion called meniscus cartilage. When people talk about knee cartilage, they may be talking about either the meniscus cartilage or the articular cartilage. 3 Bones of the Lower Extremity Science Picture Co / Getty Images The lower extremity includes the femur, the tibia, and foot and ankle bones. We call the segment between the hip and knee the thigh, and we call the segment between the knee and ankle the leg. Some people confuse the words leg and lower extremity, but in anatomic terms the leg spans only the distance from the knee to the ankle. 4 AP Knee X-Ray Image © Jonathan Cluett, MD An X-ray is one of the most common imaging tests used to diagnose a knee problem. The image here is a front-to-back view of the knee joint, also called the AP view. (AP stands for anteroposterior, meaning the image is directed from the front to the back of the knee joint.) 5 Lateral Knee X-Ray Image © Medical Multimedia Group While an AP X-ray looks from front-to-back of the knee joint, a lateral view looks from the side of the joint. Lateral X-rays are particularly helpful at seeing the kneecap, or patella, and the cartilage space behind the kneecap. 6 Knee Arthritis 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, causing pain, stiffness, and trouble moving. 7 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. Surgery for Knee Injuries 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. Boston Medical Center. Common Knee Injuries. Harvard Health Publishing. X-ray may be best screening tool for diagnosing knee pain. Lee Y. C. (2013). Effect and treatment of chronic pain in inflammatory arthritis. Current rheumatology reports, 15(1), 300. doi: 10.1007/s11926-012-0300-4 Centers for Disease Control and Prevention. Osteoarthritis (OA). 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 The Cleveland Clinic. Total Knee Replacement Surgery. Additional Reading Joseph AM, Collins CL, Henke NM, Yard EE, Fields SK, Comstock RD. A multisport epidemiologic comparison of anterior cruciate ligament injuries in high school athletics. J Athl Train. 2013;48(6):810-817. doi:10.4085/1062-6050-48.6.03 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. See Our Editorial Process Meet Our Medical Expert Board Share Feedback Was this page helpful? Thanks for your feedback! What is your feedback? Other Helpful Report an Error Submit