The Anatomy and Actions of the Knee Essay

The knee is an integral joint in terms of movement, but this joint absorbs much impact while it supports the weight of the body. Depending on the type of activities that you engage in, the level of impact absorbed by your knee may vary. The knee joint connects the kneecap (the patella) with the second bone in the lower part of the leg (the fibula). It also connects the shin bone (the tibia) with the thigh bone (the femur). Four ligaments serve to stabilize the joint; these ligaments are known as the Lateral Collateral Ligament, Medial Collateral Ligament, Posterior Cruciate Ligament, and the Anterior Cruciate Ligament.

Answer: TRUE Diff: 2 Page Ref: 255 21) Dislocations in the TMJ almost always dislocate posteriorly with the mandibular condyles ending up in the infratemporal fossa. Answer: FALSE Diff: 2 Page Ref: 268-269 22) Symphyses are synarthrotic joints designed for strength with flexibility. Answer: FALSE Diff: 2 Page Ref: 251 Multiple-Choice Questions 1) A fibrous joint that is a peg-in-socket is called a ________ joint. A) syndesmosis B) suture C) synchondrosis D) gomphosis Answer: D Diff: 2 Page Ref: 250 2) The cruciate ligaments of the knee ________. A) tend to run parallel to one another B) are also called collateral ligaments C) prevent hyperextension of the knee D) assist in defining the range of motion of the leg Answer: C Diff: 2 Page Ref: 263-264 3) Articular cartilage found at the ends of the long bones serves to ________. A) attach tendons B) produce red blood cells (hemopoiesis) C) provide a smooth surface at the ends of synovial joints D) form the synovial membrane Answer: C Diff: 1 Page Ref: 251

First and foremost, your knee has four ligaments. The ligaments line up your bones and help control the way you move. It prevents the shins from moving too far forward. ACL injuries sometimes requires surgery.

Ligament - Ligaments determine how much the joints can move so each joint is stabilized.

The popliteus muscle is a minor flexor of the knee. It penetrates the joint capsule to find its origin on the lateral condyle of the femur, and passes obliquely to insert on the medio-proximal tibia. Its main function is to help stabilize the knee, but is also able to rotate the femur on the tibia to unlock the knee.

It is a modified hinge joint that allows flexion and extension, as well as anterior and posterior gliding and minimal rotation. The bony articulations of the knee include medial and lateral tibio-femoral articulations and a patello-femoral articulation. There is also an articulation between the head of the fibula and the tibia, but the fibula does not bear weight and is not considered part of the knee joint itself. The afore-mentioned articulating surfaces are incongruous, and the stability of the knee relies mostly on the integrity of the supporting muscles and ligaments. The muscles that span the knee are the quadriceps anteriorly, the hamstrings and gastrocnemius posteriorly, and the tensor fascia latae (iliotibial band) laterally (Moore 2014).

The bony anatomy involved in drop foot are the ankle bones, known as the tibia, fibula, and talus, which make up the talocrural joint. The talocrural joint is a synovial joint that is the true ankle joint. It is functionally a hinge type of joint that permits dorsiflexion and plantar flexion in the foot. The talocrural joint is attached medially by the deltoid ligament, which is made up of the anterior tibiotalar ligament, tibiocalcaneal ligament, posterior tibiotalar ligament and the tibionavicular ligament. The muscles involved in the drop foot are the muscles that dorsiflex the foot and are more superficial. These muscles include the tibialis anterior, the extensor halluces longus, and the extensor digitorum longus. The tibialis anterior originates from the upper half of the lateral shaft of the tibia and the interosseous membrane, while it inserts on the inferomedial aspect of medial cuneiform and the base of 1st metatarsal. Its action is to extend and invert the foot at the ankle; and it also holds up medial longitudinal arch of the foot. The extensor halluces longus originates on the middle half of the anterior shaft

A joint is the site where two skeletal elements connect(1). Joints can be classified by both structure and function. Structural classifications are based on the type of connective tissue binding the structures together and whether a joint capsule is present(2, 3). There are three structural classifications of joints; fibrous, cartilaginous and synovial. Functional classifications are based on the amount of movement present(2). There are three functional classifications of joints; synarthroses which are immobile, amphiarthroses which are slightly mobile, and diarthroses which are freely mobile(3).

The knee joint consists of four ligaments, two intra-capsular which are the ACL and the PCL and two extra-capsular ligaments including the MCL and LCL. The ACL is an extremely strong stabiliser which prevents anterior displacement of the knee. The ACL is a ligament and therefore connects one bone to another, the femur with the tibia. The ACLs origin is from the anterior intercondylar eminence of the tibia (home,2017) and the fibres pass upwards, backward and laterally inserting into the lateral condyle of the femur.

All of these things combine together and make the knee joint; the bones, the femur the patella, the tibia, and the fibula, the tendons the quadriceps and the patellar and the patellar tendons. The ligaments the MCL, LCL, PCL, ACL and depending if you want to count the patellar tendon as a ligament then it is a ligament. The muscles that help the knee and leg move the quadriceps and the hamstrings. And are vital and necessary for the knee joint to work correctly. Now that I have given you a crude and simple explanation of what makes up the knee joint it is time I explained to you what exactly what a knee tear is.

The posterior and inferior transverse tibiofibular ligaments combine to provide 40-50 % of the resistance to diastatic stress. The AITFL contributes approximately 35 % of the resistance to this stress with the remaining stability (20-25%) coming from the interosseous membrane (IOM).21 The IOM also restrains posterolateral bowing of the fibula and transmits a small portion of the load from the tibia to the fibula during weight bearing. Both the anterior and posterior tibiofibular ligaments check excessive external rotation of the fibula. (15)

The knee is a joint that is located about halfway between the hips and the feet. It is the place where three long leg bones, the femur or thigh bone, the tibia and the fibula or shin bones, meet at the patella, or knee cap. There are also ligaments, tendons and cartilage that connect the bones to one another and allow for movement of the leg. The tibia is the larger shin bone and it is located in the front. The fibula is in the back of the shin. At the website, Brain Lab (2017) it say, “Two ligaments are located on the outside of the knee joint. These ligaments connect the femur to the tibia and the fibula. They help manage side-to-side movements in the knee” (Brain Lab, 2017).

The knee is actually three separate joints. Two are between the femur and the tibia and one is between the patella and the patellar femur. There are two ligaments that help to stabilize the knee. These are the anterior cruciate ligament (acl) and the medial collateral ligament (mcl). Each ligament has a special function to help maintain knee stability in many different positions. At full extension, a slight lateral rotation of the

the joint to work. For example the Knee joint is a synovial joint. Where the femour and tibia meet the

There are three types of joins in the skeletal system each allowing different types of movements.