The Knee Joint
Introduction
The knee is one of the largest and most complex joints in the body. The knee joins the femur to the tibia. The smaller bone that runs alongside the tibia is the fibula. The patella, also known as the knee-cap, is another one that makes up the knee joint. I decided to discuss this joint structure because of reoccurring knee injuries.
The Knee Joint
The knee joint is formed by the articulation of the distal end of the femur and the proximal end of the tibia. The fibula serves as an attachment site for connective tissue. The knee is a diarthrotic, hinge type joint. The two articulating ends of the tibia are encased in a capsule that lubricates the joint with synovial fluid to reduce friction. The C-shaped medial and lateral menisci serve to deepen the articulation at the superior surface of the joint. Adding to the joints stability are the two major pairs of ligaments: the cruciates and collaterals.(1) The knee is part of a chain that includes the pelvis, hip, and upper leg above, and the lower leg, ankle and foot below. All of these work together and depend on each other for function and movement.
The cruciates are name 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. These ligaments are vital in maintaining the anterior and posterior stability of the knee joint, as well as its rotary stability. The medial and lateral collateral ligaments have a stabilizing effect in the frontal plane of motion, helping to prevent sideward displacement and over rotation. The medial collateral attaches the femur to the tibia, also attaching the medial meniscus. The lateral collateral attaches the femur
The knee is one of the largest and most complex joints in the body. The knee joins the femur to the tibia. The smaller bone that runs alongside the tibia is the fibula. The patella, also known as the knee-cap, is another one that makes up the knee joint. I decided to discuss this joint structure because of reoccurring knee injuries.
The Knee Joint
The knee joint is formed by the articulation of the distal end of the femur and the proximal end of the tibia. The fibula serves as an attachment site for connective tissue. The knee is a diarthrotic, hinge type joint. The two articulating ends of the tibia are encased in a capsule that lubricates the joint with synovial fluid to reduce friction. The C-shaped medial and lateral menisci serve to deepen the articulation at the superior surface of the joint. Adding to the joints stability are the two major pairs of ligaments: the cruciates and collaterals.(1) The knee is part of a chain that includes the pelvis, hip, and upper leg above, and the lower leg, ankle and foot below. All of these work together and depend on each other for function and movement.
The cruciates are name 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. These ligaments are vital in maintaining the anterior and posterior stability of the knee joint, as well as its rotary stability. The medial and lateral collateral ligaments have a stabilizing effect in the frontal plane of motion, helping to prevent sideward displacement and over rotation. The medial collateral attaches the femur to the tibia, also attaching the medial meniscus. The lateral collateral attaches the femur
References: Floyd R.T. Manual of Structural Kinesiology. 8th ed. The Knee Joint. New York: McGraw-Hill, 2012. Grogan, Brianne. Normal Range of Motion of the Knee. August 16, 2013. Available at: http://www.livestrong.com/article/normal-range-motion-knee Howley Edward T. and Powers Scott K. Exercise Physiology. 8th ed. Training for the Female Athlete, Children, Special Population, and the Masters Athlete. New York: McGraw-Hill, 2012. Dahm, D. and Smith, J. MayoClinic. Fitness for Everybody. Rochester, MN: MayoClinic, 2005. Waehner, Paige. Exercise 101-The Basic Principles of Exercise. February 16, 2012. Available at: http://www.Exercise.about.com/cs/exbeginners/a/exbasics.3.htm