The knee joint is formed by the articulation of the distal end of the femur and the proximal end of the tibia. The fibula is only involved to the extent that it serves as an attachment site for connective tissue. In this paper, the anatomy of the joint will be discussed.
The knee is a hinge-type, diarthrotic, or freely moveable joint. Also referred to as a synovial joint, the 2 articulating ends of bone are encased in a capsule that lubricates the joint with synovial fluid to reduce friction.
Each bone in a synovial joint has articular cartilage at the articulating surface. The C-shaped medial and lateral menisci serve to deepen the articulation at the superior surface of the tibia, thus enhancing the bony stability of the joint.
Also adding to the joints stability are the two major pairs of ligaments: the cruciates and the collaterals. The medial and lateral collateral ligaments have a stabilizing effect in a lateral plane of motion, helping to prevent sideward displacement and over-rotation. The medial collateral attaches the femur to the tibia, also attaching to the medial meniscus. The lateral collateral attaches the femur to the fibula but has no attachment to the lateral meniscus. Both collaterals lie slightly posterior to the lateral axis of the knee joint and are taut when the knee is full extension. This positioning of the ligaments causes a slackness when flexion occurs, allowing medial and lateral rotation to take place.
The cruciate ligaments are so named because of their cross-configuration within the joint. The anterior cruciate ligament attaches to the tibia on its anterior-superior surface, crossing through the joint from the medial side to its lateral attachment on the femur. The posterior cruciate ligament attaches on the posterior-superior aspect of the tibia, crossing diagonally and medially to its lateral attachment on the femur. The anterior and posterior cruciates protect against hyperextension and hyperflexion, respectively.
The actions performed at the knee include flexion, extension, and medial and lateral rotation.
Flexion is the bending of a joint so that the angle between the two bones decreases. The primary muscles that flex the knee are a group collectively known as “hamstrings.” The hamstrings consist of the biceps femoris, semitendinosus, semimembranosus. The muscles that assist in flexion are the sartorius, gracilis,...
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...g Linea aspera on posterior femur, greater trochanter of femur
Insert Patella and via patellar tendon to tibial tuberosity
Action Extension of knee
Nerve Femoral
VASTUS INTERMEDIUS
Orig Anterior and lateral femoral shaft
Insert Patella and via patellar tendon to tibial tuberosity
Action Extension of the knee
Nerve Femoral
VASTUS MEDIALIS
Orig Linea aspera on posterior femur
Insert Patella and via patellar tendon to tibial tuberosity
Action Extension of knee
Nerve Femoral
TENSOR FASCIA LATA
Orig Iliac crest (posterior to ASIS)
Insert Iliotibial tract (which continues to attach to the lateral condyle of the tibia)
Assists extension of knee
Nerve Superior gluteal
In order for athletes to save their active lifestyles they need understand the ACL. The ACL is the most important ligament in the knee because it provides stability to the knee. Athletes have to be aware of the importance of the ACL and know its functions in order to preserve the ligament. The ACL otherwise know as the anterior cruciate ligament is the ligament in the knee that connects the upper leg bone which is the femur to the lower leg bone which is the tibia. The anterior cruciate ligament crosses with the posterior cruciate ligament inside the center of the knee joint to stabilize to the knee in movement.
To understand the importance of the ACL, the knee as a whole must be examined. The knee is formed by the femur, the tibia, and the patella. Several muscles and ligaments control the motion of the knee and protect it from damage at the same time. Ligaments are dense structures of connective tissue that fasten bone to bone and stabilize the knee. Two ligaments on either side of the knee, called the medial and lateral collateral ligaments, stabilize the knee from side-to-side. The ACL along with the posterior cruciate ligament are of a pair of ligaments in the center of the knee joint that form a cross. T...
Nisell R. (1985) Mechanics of the knee: A study of joint and muscle load with clinical applications. Acta Orthop Scand 216; 1-42.
The suspensory ligament is found down the back of the cannon bone that starts just below the knee or hock and splits into two parts that pass around the back of the ankle and end on the front of the long pastern bone. Acute front suspensory ligament injuries are most commonly found in eventers and jumpers due to the speed and the increasing load on the forelimbs from jumping and the chance of misstep.
The Anterior Cruciate Ligament (ACL) attaches the femur, which is the thighbone, and the tibia, which is the shin, together (northstar). A torn ACL is one of the most excruciating experiences in an athlete’s life. It is the first thing that comes to mind when they hurt their knee on the field; for many it is their greatest fear. A torn ACL can sometimes mean the end of an athlete’s career. It can mean losing the chance to get that scholarship for young athletes, and it can also mean the end of those million dollar paychecks for those who have gone professional. A torn ACL can result in numerous surgeries, months of vigorous exercise and rehabilitation, and a sufficient amount of pain. It requires complete patience, for pushing too hard can result in further, more painful injury. Even after all that, an athlete is not guaranteed he or she will ever be able to play sports again.
The anterior cruciate ligament (ACL) is one of four major ligaments of the knee joint: anterior (front) cruciate ligament, posterior (back) cruciate ligament (PCL), medial (inside) collateral ligament (MCL), and lateral (outside) collateral ligament (LCL). The ACL primarily works to coordinate function, promote overall stability of the knee, and prevent any unnecessary forward movement of the tibia. Many studies have attempted to determine why the ACL is associated with a high incidence of tears. There are nearly 200,000 annual cases of knee injury, with roughly 100,000 of these knees reconstructed (9). According to the Journal of Sports Medicine Orthopedic Surgery, injury to the ACL is most predominant in populations aged
“The anterior cruicate ligament is a strong band that arises from the posterior middle part of the lateral condyle of the femur, it passes anteriorly and inferiorly between the condyle, and is attached to the depression in front of the intercondylar eminence of the tibia (Mosby‘s page. 105).” The tear of the A.C.L is described as a partial or complete rupture of the anterior cruciate ligament. The A.C.L. does not repair by itself. It is so important to an athlete in most sports because an athlete has to be able to rotate the knee in specific directions. The tear happens more frequently in soccer, basketball, and volleyball. Athletes who started participating in a sport while they were young have a greater chance of sustaining a tear. Women are more susceptible to this injury than men. Theories for this include hormonal, environmental, and biomechanical factors. “Women‘s muscles react differently in landing. Doctors say that women land with straighter legs than men do; thus, they pass their shock to the A.C.L. resulting in a tear. Environmental factors are shoes and playing surfaces.” (Patrick, Dick)
...cient knee during activities of daily living, as they have yet to be determined ⁷². In understanding the factors contributing to the mechanism of non-contact ACL injury, investigators should consider whether the kinematics, kinetics and muscle activation strategies observed are the cause of increased ACL strain or compensation for other kinetic chain insufficiencies ²⁹. Further knowledge on how movement patterns and other kinetic chain structures affect ACL loads prove critical in enhancing future prevention strategies ²⁹ ³⁴. As with reconstruction, rehabilitation should aim to aid the knee in attaining its near-normal function ⁵⁵. Through producing rehabilitation programmes built around existing knowledge on the biological and mechanical properties of the ACL, objectives such as reduced pain, greater ROM and improved muscle function can be achieved ⁵⁵.
These exercises build strength and endurance in your knee. Endurance is the ability to use your muscles for a long time, even after they get tired.
The anterior cruciate ligament, also known as the ACL, is one of the four main ligaments within the knee that connect the femur to the tibia. It is also common to tear the ACL if one plays a sport. When one tears it, they hear or feel a pop, on might also feel that their knee just gave out. The knee will begin to swell up and be too painful to continue any sport or activity they were playing. The ACL is a ligament so when someone tears it, the ligament may no longer be attached to the bone. So the bones in your knee will move abnormally and start buckling.
The medial meniscus is larger and more oval or C-shaped in the outline than the lateral meniscus. The medial cartilage is also more firmly fixed to the tibia and the capsule than the lateral meniscus; as a result, it is much more frequently injured than the lateral cartilage.
In order to know how bad a dislocated knee is, the anatomy of the knee should be known. The top bone in the joint is called the femur and the bone that is connected to is the tibia, which is distal it (Prentice, 20142013). Next to the tibia laterally is the fibula (Prentice, 20142013). These bones form the knee joint. I...
“Doc, I fell and twisted my knee. I heard a pop. It hurt briefly. When I stood up, the knee felt as if it was not underneath me, and the knee gave way. It swelled up by the next day and ever since feels as though it would pop out when I twist or even cross the street quickly.” In almost all cases the above complaints occur due to an injury to the ACL (Anterior Crucial Ligament) of the knee. The ACL is a very important ligament in the knee that controls the pivoting motion of the knee. This joint guides the femur and tibia through a regular range of motion. It is the most common and serious of injury sustained to the knee (Duffy, f9). How this injury happens, who is most susceptible, and how it is treated are a few questions athletes are becoming heavily concerned with.
Hinge joints are formed between two or more bones where the bones can only move along one axis to flex or extend. One of the simple hinge joints in the body is the interphalangeal joints which are between the phalanges of the fingers and toes. In these hinge joints, the bones are able to flex to decrease the angle between them and extend to increase their angle to 180 degrees when holding the foot or hand flat. Little body weight and mechanical force are exerted. They are made up of simple synovial joint material with little accessory ligaments for reinforcement. Each bone is capped with a thin layer of a smooth hyaline cartilage to reduce friction in the joint and to absorb the shock of the joint being compressed. The bones are surrounded by a capsule of fibrous connective tissue lined with synovial membrane. The joint capsule at these joints forms the knuckle that is visible through the skin that covers
Two ligaments in the knees are most likely to be injured. The anterior cruciate ligament (ACL) is in the center of the knee. It is often injured by a twisting motion, such as pivoting wrong or falling awkwardly. This unfortunately is one of the ligaments that I tore. The other ligament, the medial collateral ligament (MCL) is on the inside of the knee. It is normally injured from a blow to the side of the knee. This is common in contact sports such as football and soccer. Injury to either ligament causes pain and weakens the knee joint. Without treatment, the patient may develop many other knee problems that can have lasting effects.