Knee joint

A complex joint that facilitates movement of the lower limb while providing stability and support.

The knee joint is a hinge joint formed where the femur (thigh bone) meets the tibia (shin bone) and fibula. It is one of the largest and most complex joints in the body, comprising three distinct compartments: the medial and lateral tibiofemoral joints, as well as the patellofemoral joint. It is surrounded by a joint capsule and is stabilized by various ligaments and tendons that maintain its structural integrity during movement.

Terminologia Anatomica

articulatio genus

System

Musculoskeletal system

Function

The primary function of the knee joint is to allow for a range of movements, primarily flexion and extension, which are essential for walking, running, and jumping. The knee serves as a vital load-bearing joint, supporting the body's weight and absorbing the impact during activities. Additionally, the knee joint acts as a pivot point for the rotation of the lower leg, especially when in a flexed position, allowing for movements that require agility and balance. The rich network of muscles surrounding the knee also plays a critical role in controlling and stabilizing its movement, enhancing overall mobility and function.

Location

Situated at the junction of the thigh and lower leg, the knee joint is located centrally along the length of the body, allowing it to connect the upper leg to the lower leg. More specifically, it lies approximately in line with the patella (kneecap) at the front, resting above the tibia and below the femur. The joint is easily accessible, located between the femur, tibia, and fibula, and encased in a protective capsule that contains synovial fluid, providing lubrication for smooth motion. Its positioning makes it critical for locomotion and stabilization when standing.

Did You Know?

The knee joint is often referred to as a 'hinge joint,' but it also allows for slight rotational movement, especially when bent.
Injuries to the knee are among the most common musculoskeletal problems, often affecting athletes and active individuals.
The knee joint can withstand significant forces, with the capability to support up to five times the body's weight during activities like running and jumping.
The meniscus, two C-shaped cartilaginous structures within the joint, play a crucial role in shock absorption and joint stability.