Knee joints
Diagram of human knee
Latin	articulatio genus
Gray's	subject #93 339
Nerve	femoral, obturator, sciatic
MeSH	Knee
Dorlands/Elsevier	a_64/12161228

The knee is the lower extremity joint connecting the femur, fibula,patella, and the tibia.^[1] Since in humans the knee supports nearly the entire weight of the body, it is the joint most vulnerable both to acute injury and to the development of osteoarthritis. Download high resolution version (800x729, 63 KB)Knee. ... For other uses, see Latins and Latin (disambiguation). ... For other uses, see Nerve (disambiguation). ... The femoral nerve, the largest branch of the lumbar plexus, arises from the dorsal divisions of the second, third, and fourth lumbar nerves. ... The Obturator Nerve arises from the ventral divisions of the second, third, and fourth lumbar nerves; the branch from the third is the largest, while that from the second is often very small. ... The sciatic nerve (also known as the ischiatic nerve) is a large nerve that runs down the lower limb. ... Medical Subject Headings (MeSH) is a huge controlled vocabulary (or metadata system) for the purpose of indexing journal articles and books in the life sciences. ... Elseviers logo. ... Knee may mean (besides a knee joint typical of mammals): Look up knee in Wiktionary, the free dictionary. ... For other uses, see Joint (disambiguation). ... The femur or thigh bone is the longest, most voluminous, and strongest bone of the mammalian bodies. ... For other uses, see Patella (disambiguation). ... This article is about the vertebrate bone. ... Osteoarthritis (OA, also known as degenerative arthritis, degenerative joint disease, or in more colloquial terms wear and tear), is a condition in which low-grade inflammation results in pain in the joints, caused by wearing of the cartilage that covers and acts as a cushion inside joints and destruction or...

Human anatomy

Upon birth, a baby will not have a conventional knee cap, but a growth formed of cartilage. In human females this turns to a normal bone knee cap by the age of 3, in males the age of 5.

The knee is a complex, compound, condyloid variety of a synovial joint which hovers. It actually comprises two separate joints. Synovial joints (or diarthroses, or diarthroidal joints) are the most common and most moveable type of joints in the body. ...

• The femoro-patellar joint consists of the patella, or "kneecap", a so-called sesamoid bone which sits within the tendon of the anterior thigh muscle (m. quadriceps femoris), and the patellar groove on the front of the femur through which it slides.

• The femoro-tibial joint links the femur, or thigh bone, with the tibia, the main bone of the (lower) leg. The joint is bathed in a viscous (synovial) fluid which is contained inside the "synovial" membrane, or joint capsule.

The Febulus Remus is a part of the knee not known to many doctors or scientists, between the ligament and the bone of the knee joint, which is a vital part in strengthening the knee and leg. For other uses, see Patella (disambiguation). ... In anatomy, a sesamoid bone is a bone embedded within a tendon. ... Quads redirects here. ... The articular surface of the lower end of the femur occupies the anterior, inferior, and posterior surfaces of the condyles. ... The femur or thigh bone is the longest, most voluminous, and strongest bone of the mammalian bodies. ... This article is about the vertebrate bone. ... Synovial fluid is a thin, stringy fluid found in the cavities of synovial joints. ... The joint capsules or articular capsules form complete envelopes for the freely movable bone joints. ...

The recess behind the knee is called the popliteal fossa. It can also be called a "knee pit." The popliteal fossa is a space or shallow depression located at the back of the knee-joint. ...

Ligaments

The anterior cruciate ligament (or ACL) is one of the four major ligaments of the knee. ... The lateral condyle is one of the two projections on the lower extremity of femur. ... The anterior intercondyloid fossa (or intercondylar area) is the location where the anterior cruciate ligament attaches to the tibia. ... Diagram of the knee The posterior cruciate ligament (or PCL) is one of the four major ligaments of the knee. ... The medial condyle is one of the two projections on the lower extremity of femur. ... Posteriorly, the medial condyle and lateral condyle are separated from each other by a shallow depression, the posterior intercondyloid fossa (or intercondylar area), which gives attachment to part of the posterior cruciate ligament of the knee-joint. ... The joint capsules or articular capsules form complete envelopes for the freely movable bone joints. ... The Patellar ligament (anterior ligament) is the central portion of the common tendon of the Quadriceps femoris, which is continued from the patella to the tuberosity of the tibia. ... For other uses, see Patella (disambiguation). ... Narrow below where the anterior surfaces of the condyles of the tibia end in a large oblong elevation, the tuberosity of the tibia, which gives attachment to the ligamentum patellae. ... In human anatomy, the quadriceps tendon connects the quadriceps femoris muscles to the superior aspects of the patella on the anterior of the thigh. ... Categories: Move to Wiktionary | Anatomy stubs ... The femur or thigh bone is the longest, most voluminous, and strongest bone of the mammalian bodies. ... The medial collateral ligament or MCL (or tibial collateral ligament) is one of the four major ligaments of the knee. ... The medial epicondyle of the femur is a large convex eminence to which the tibial collateral ligament of the knee-joint is attached. ... The medial condyle is the medial portion of the upper extremity of tibia. ... In orthopedics, a valgus deformity is a term for the outward angulation of the distal segment of a bone or joint. ... Diagram of the knee The lateral collateral ligament (or LCL) is one of the four major ligaments of the knee. ... The lateral epicondyle of the femur, smaller and less prominent than the medial epicondyle, gives attachment to the fibular collateral ligament of the knee-joint. ... The upper extremity or head of the fibula is of an irregular quadrate form, presenting above a flattened articular surface, directed upward, forward, and medialward, for articulation with a corresponding surface on the lateral condyle of the tibia. ... In orthopedics, a varus deformity is a term for the inward angulation of the distal segment of a bone or joint. ... The oblique popliteal ligament (posterior ligament) is a broad, flat, fibrous band, formed of fasciculi separated from one another by apertures for the passage of vessels and nerves. ... The medial condyle is the medial portion of the upper extremity of tibia. ... The arcuate popliteal ligament is an extracapsular ligament of the knee. ... The lateral condyle is one of the two projections on the lower extremity of femur. ... For other uses see fibula (disambiguation) The fibula or calf bone is a bone placed on the lateral side of the tibia, with which it is connected above and below. ...

Menisci

These are cartilaginous elements within the knee joint which serve to protect the ends of the bones from rubbing on each other and to effectively deepen the tibial sockets into which the femur attaches. They also play a role in shock absorption. There are two menisci in each knee, the medial meniscus and the lateral meniscus. Either or both may be cracked, or torn, when the knee is forcefully rotated and/or bent. In anatomy, a meniscus is a moon-shaped figure. ... The medial meniscus is a fibrocartilage band that spans the medial knee, and lies on the head of the tibia. ... The lateral meniscus, also called the external semilunar fibrocartilage is a fibrocartilaginous band that spans the lateral knee. ...

Movements

The knee permits the following movements: flexion, extension, as well as slight medial and lateral rotation. Also, the knee has special locking and unlocking mechanisms, related to movement by the femoral condyles on the tibial plateau. The ligaments and menisci, along with the muscles which traverse the joint, prevent movement beyond the knee's intended range of motion. It is also classified as a hinge joint. In anatomy, Flexion is movement whereby bones or other objects are brought closer together. ... In metaphysics, extension is the property of taking up space; see Extension (metaphysics). ... In anatomy, a meniscus is a moon-shaped figure. ...

The range of movement is as follows: Flexion is permitted up to 120º when the hip is extended, 140º when the hip is flexed and 160º when the knee is flexed passively. Medial rotation is limited to 10º and lateral rotation to 30º .

Blood supply

The femoral artery and the popliteal artery help form the arterial network surrounding the knee joint (articular rete). There are 6 main branches:

• 1. Superior medial genicular artery
• 2. Superior lateral genicular artery
• 3. Inferior medial genicular artery
• 4. Inferior lateral genicular artery
• 5. Descending genicular artery
• 6. Recurrent branch of anterior tibial artery

The medial genicular arteries penetrate the knee joint The medial superior genicular runs in front of the Semimembranosus and Semitendinosus, above the medial head of the Gastrocnemius, and passes beneath the tendon of the Adductor magnus. ... The lateral superior genicular passes above the lateral condyle of the femur, beneath the tendon of the Biceps femoris, and divides into a superficial and a deep branch; the superficial branch supplies the Vastus lateralis, and anastomoses with the descending branch of the lateral femoral circumflex and the lateral inferior... The medial inferior genicular first descends along the upper margin of the Popliteus, to which it gives branches; it then passes below the medial condyle of the tibia, beneath the tibial collateral ligament, at the anterior border of which it ascends to the front and medial side of the joint... The lateral inferior genicular runs lateralward above the head of the fibula to the front of the knee-joint, passing in its course beneath the lateral head of the Gastrocnemius, the fibular collateral ligament, and the tendon of the Biceps femoris. ... The descending genicular artery (highest genicular artery) arises from the femoral just before it passes through the opening in the tendon of the Adductor magnus, and immediately divides into a saphenous and a musculo-articular branch. ...

Injury

Model demonstrating parts of an artificial knee

In sports that place great pressure on the knees, especially with twisting forces, it is common to tear one or more ligaments or cartilages. An increasingly common victim to injury is the anterior cruciate ligament, often torn as a result of a rapid direction change while running or some other, violent twisting motion. It can also be torn by extending the knee forcefully beyond its normal range. In some such cases, other structures incur damage as well. Especially debilitating is the unfortunately common "unhappy triad" of torn medial collateral and anterior cruciate ligaments and a torn medial meniscus. This typically arises from a combination of inwards forcing and twisting. Image File history File linksMetadata Download high-resolution version (2912x4368, 1090 KB) Work by Rama File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): Knee Metadata This file contains additional information, probably added from the digital camera or scanner... Image File history File linksMetadata Download high-resolution version (2912x4368, 1090 KB) Work by Rama File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): Knee Metadata This file contains additional information, probably added from the digital camera or scanner... There are very few or no other articles that link to this one. ...

Before the advent of arthroscopy and arthroscopic surgery, patients having surgery for a torn ACL required at least nine months of rehabilitation. With current techniques, such patients may be walking without crutches in two weeks, and playing some sports in but a few months. In Australian rules football, knee injuries are among the most common, especially in ruck contests, involving the crashing of two knees during the leap. These injuries forced new rule changes for the 2005 season. Arthroscopy (also called arthroscopic surgery) is a minimally invasive surgical procedure in which an examination and sometimes treatment of damage of the interior of a joint is performed using an arthroscope, a type of endoscope that is inserted into the joint through a small incision. ... Arthroscopic surgery, also known as arthroscopy, is the process where a joint is operated on using an arthroscope, a small fibre optic camera. ... Knees following ACL reconstruction surgery. ... High marking is a key skill and spectacular attribute of Australian rules football Precise field and goal kicking using the oval shaped ball is the key skill in Australian rules football Australian rules football, also known as Australian football, Aussie rules, or simply football or footy is a code of... In Australian rules football, a ruckman is a tall athletic player who contests at centre bounces and stoppages (such as boundary throw-ins and ball-ups). ...

In addition to developing new surgical procedures, ongoing research is looking into underlying problems which may increase the likelihood of an athlete suffering a severe knee injury. These findings may lead to effective preventive measures, especially in female athletes, who have been shown to be especially vulnerable to ACL tears from relatively minor trauma. Techniques to minimize the risk of an ACL injury while skiing are published by Vermont Safety Research

Animal anatomy

Look up knee in Wiktionary, the free dictionary.

In humans the knee refers to the joints between the femur, tibia and patella. In quadrupeds, particularly horses and ungulates the term is commonly used to refer to the carpus, probably because of its similar hinge or ginglymus action. The joints between the femur, tibia and patella are known as the stifle in quadrupeds. In insects and other animals the term knee is used widely to refer to any ginglymus joint. Wikipedia does not have an article with this exact name. ... Wiktionary (a portmanteau of wiki and dictionary) is a multilingual, Web-based project to create a free content dictionary, available in over 151 languages. ... Ungulates (meaning roughly hoofed or hoofed animal) make up several orders of mammals, of which six survive: Artiodactyla: even-toed ungulates, cattle, sheep, goats, pigs, antelope, and many others Cetacea: whales and dolphins (which evolved from hoofed land animals) Perissodactyla: odd-toed ungulates such as horses and rhinos Proboscidea: elephants... This article is about Carpal bones. ... In the hinge joint (ginglymus), the articular surfaces are moulded to each other in such a manner as to permit motion only in one plane, forward and backward, the extent of motion at the same time being considerable. ... The stifle joint is complicated joint inside the body of a horse or dog similar to that of the human knee. ...

See also

• Cartilage
• Knee Cartilage Replacement Therapy
• Knee examination
• Kneebar
• Reflex hammer

Cartilage is a type of dense connective tissue. ... // Articular cartilage, most notably that which is found in the knee joint, is generally characterized by very low friction, high wear resistance, and poor regenerative qualities. ... The knee examination, in medicine, is performed as part of a physical examination, or when a patient presents with knee pain or a history that suggests a pathology of the knee joint. ... The leglock is a joint lock in martial arts which attacks the opponents leg joints, usually the knee but less commonly the hip. ... A reflex hammer is a medical instrument used by physicians to test deep tendon reflexes. ...

Additional images

Knee MR Image File history File links No higher resolution available. ...	Knee MR Image File history File links No higher resolution available. ...	Knee X-ray Image File history File linksMetadata No higher resolution available. ...	Cruciate ligaments Image File history File links No higher resolution available. ...
Female knee Image File history File links No higher resolution available. ...	Male knee Image File history File links Metadata Size of this preview: 450 × 600 pixelsFull resolution‎ (2,448 × 3,264 pixels, file size: 404 KB, MIME type: image/jpeg) File historyClick on a date/time to view the file as it appeared at that time. ...	Left knee-joint from behind, showing interior ligaments. Image File history File links Gray348. ...	Capsule of right knee-joint (distended). Lateral aspect. Image File history File links Gray351. ...

References

2008 (MMVIII) is the current year, a leap year that started on Tuesday of the Anno Domini (or common era), in accordance to the Gregorian calendar. ... is the 15th day of the year in the Gregorian calendar. ...

External links

• The KNEEguru - an educational site packed with knee content
• Cartilage Health - Information on knee articular cartilage injury prevention, repair and rehabilitation
• Patient Information for all knee issues
• treatment by Alimorad Farshchian, MD
• London Knee Clinic
• The Knee - useful resource from the University of Glasgow
• The Knee Library
• Knee1
• Anatomy at Dartmouth knee/index
• Total Knee Replacement

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