As one of the largest and most advanced joints in the human body, the knee is critical to mobility. Its complex structure and constant utilization causes it to be particularly vulnerable to damage. Although the knee’s essential utility in the human body is universally known, many people are unaware of its complexity and the numerous pieces that converge to ensure it operates properly.
The anatomy of the knee extends well beyond the knee joint itself, as its constituents include bones, tendons, ligaments, muscles, and cartilage. Injuries to any of the following individual components will hinder the overall functionality of the knee:
The joint capsule surrounding the entire knee contains the synovial membrane, which provides nourishment to all constructs surrounding the knee. Ligaments surrounding the capsule provide it with support.
There are four bones connecting at the knee:
Ligaments present in and around the knee are essential in maintaining its stability as they connect the femur bone to the tibia bone and therefore, damage to them will almost certainly constrain an individual’s mobility. These four ligaments are as follows:
More commonly referred to as the knee’s cartilage, the menisci exist in two places: the outer edges and inner edges of the tibia bone. The role of the menisci is to absorb shock to the knee and evenly distribute weight between the tibia and femur bones.
The cartilage of the knee is an elastic tissue known as articular cartilage that serves the purpose of protecting the bones and allowing the joints to move smoothly. Like the menisci, the cartilage also absorbs shock.
There are two primary muscle groups surrounding the knee, the quadriceps and hamstrings, that both play an important role in the movement and stabilization of the knee.
Quadriceps: Four muscles comprise the quadriceps, which converge to form the quadriceps tendon. The quadriceps tendon is attached to the patella, which is attached to tibia by the patellar tendon.
Hamstrings: The hamstrings muscle group is comprised of three muscles and it enables flexibility of the knee. The hamstring muscles connect to both the fibula and tibia.
|Activity||Knee Flexion (degrees)|
|Sitting down||83 -110|
|Tying a shoe||106|
Injuries to the knee typically occur as a result of movement beyond the normal range of motion, abnormal movement, or strenuous activity.
Click any of the above conditions for treatment options or more information.