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
Witvrouw, E., Mahieu, N., Roosen, P., & McNair, P. (2007). The role of stretching in tendon injuries. British journal of Sports Medicine , 224-226.
The gluteus maximus originates from both the ilium and the sacrum and inserts on the femur. The gluteus minimus abducts and rotates the thigh outward. The biceps femoris originates from the tuberosity of the ischium and is responsible for abducting the thigh and flexing the hindlimb or in humans the thigh/leg. The gastrognemius originates from the lateral sesamoid bone of the femur and extends the hindfoot in minks and the calves in humans (Scott).
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.
Lateral ligaments and their biomechanics: The anterior talofibular ligament, the calcaneofibular ligament, and the posterior talofibular ligament. When referring to the anatomic subtalar joint, the lateral complex is composed of the following ligaments: CFL, Lateral talocalcaneal ligament, the cervical ligament, and the interosseous talocalcaneal ligament.
The most common knee injury in sports is damage to the anterior cruciate ligament (ACL) through tears or sprains. “They occur in high demand sports that involve planting and cutting, jumping with a poor landing, and stopping immediately or changing directions” (University of Colorado Hospital). The ACL is a ligament that runs diagonally in the middle of the knee and found at the front of the patellar bone. Its function involves controlling the back and forth motion of the knee, preventing the tibia from sliding out in front of the femur, and providing rational stability to the knee. Interestingly, women are more prone to ACL injuries than men. The occurrence is four to six times greater in female athletes.
Therapeutic stretches of the gastrocnemius and soleus muscles. If the ligament are weakened, cross fiber friction them to try to regain some of the integrity of the ankle back.
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 anterior cruciate ligament is the reason that the knee only has one pattern of movement. Instead of moving sideways and up and down, the knee only serves as a pivot for flexion (bending) and extension (straightening); it holds the tibia and femur in place (northstar). In the northstar web page it is stated that, “The anterior cruciate ligament is one of the most important ligaments to athletes because of its main function, stabilization of the joint while decelerating.” In other words, it is the reason that we can stop abruptly without our leg collapsing. Obviously this asset makes it an essential to have a functioning ACL while playing sports. It is an especially common injury in soccer, which is a game of constant abrupt stops. Not only is soccer a danger to the ACL because of its constant stops and starts, it is also a...
The surfaces of the joint are organised to allow only back and forth motion such as bending and straightening. This type of joint can be found between your upper arm and your lower arm, in the elbow. This type of joint is incredibly important as it allows an up and down movement, without this type of joint, we wouldn’t be able to move our arm up and down. Muscles are attached to this type of joint by tendons to allow it to contract and relax and be able to move the bone within this joint. Ligaments attach the bones in a hinge joint together, for example, the humerus and the tibia are joined by ligaments but they also have antagonist muscle pairs attached to them by tendons which allow the bone to move by contraction and relaxation of the muscles.
Ligaments are tough, non-stretchable fibers that hold bones together. Damage to cruciate ligaments, which crisscross the knee to give it stability, is one of the most common sports injuries. The “tear” occurs from changing direction rapidly, slowing down from running, or landing from a jump improperly. The A.C.L tear is one injury that worries athletes in all sports at all levels because of its devastating effects. People ages 15-25 that participate in basketball and other sports that require pivoting are especially at risk.
The ligament is primarily made up of two bands, the anteromedial and posterolateral, and an intermediate band sometimes present. The ACL runs from the posteromedial portion of the lateral femoral condyle in an inferior, anterior, and medial orientation to an area just lateral to the medial tibial eminence. The posterolateral band is tightest when the knee is in extension, and the anteromedial band is tightest with the knee in flexion.
In order to understand how the menisci can be injured, you must understand the basic anatomy of the menisci and why they are important. The menisci are two oval (semilunar) fibrocartilages that deepen the articular facets of the tibia and cushion any stresses placed on the knee joint. They enhance the total stability of the knee, assist in the control of normal knee motion, and provide shock absorption against compression forces between the tibia and the femur (Booher, 2000). Articular cartilage covers the ends of the bones that make up the joint. The articular cartilage surface is a tough, very slick material that allows the surfaces to slide against one another without damage to either surface. This ability of the meniscus to spread out the force on the joint surfaces as we walk is important because it protects the articular cartilage from excessive forces occurring in any one area on the joint surface, leading to degeneration over time (Sutton, 1999).
The purpose of the squat is to train the muscles around the knees and hip joints, as well as to develop strength in the lower back, for execution of basic skills required in many sporting events and activities of daily living. Because a strong and stable knee is extremely important to an athlete or patient’s success, an understanding of knee biomechanics while performing the squat is helpful to therapists, trainers, and athletes alike (11). Because most activities of daily living require the coordinated contraction of several muscle groups at once, and squatting (a multi-joint movement) is one of the few strength training exercises that is able to effectively recruit multiple muscle groups in a single movement, squats are considered one of the most functional and efficient weight-bearing exercises whether an individual’s goals are sport specific or are for an increased quality of life
Traumatic injuries seem to occur a lot in the sport of football. Knee injuries seem to be one of the most occurring traumatic injuries in football (Become an Advocate for Sports Safety). The main types of traumatic knee injuries are: tearing/spraining of the anterior cruciate ligament (ACL), posterior cruciate ligament (PCL), medial collateral ligament (MCL), and the meniscus, which is the cartilage that is in the knee (Become an Advocate for Sports Safety). The anterior cruciate ligament (ACL) is a very vital ligament in the knee. It is the main stabilizer of the knee. Surprisingly usually the anterior cruciate ligament is torn from a non-contact twisting of the knee (5 Most Common Football injuries (and How to Prevent Them)). The knee normally pops and it will begin to swell and it may feel unstable (5 Most Common Football injuries (and How to Prevent Them)). Swelling depends on the severity in the tear of the ligament. The anterior cruciate ligament is one of the four main ligaments that provide stability to the knee joint (Common Football Injuries). It is the most important out of the four. Injuries to any of the cruciate ligaments in the knee are most of the time sprains (Common Football Injuries). The anterior cruciate ligament being the most often stretched, strained, sprained or either tore (Common Football Injuries). Most of the knee injuries that occur in footbal...