The Knee


The knee is a hinge like joint that allow human bipedal ambulation. Three structures contribute to this function - bone, cartilage, and ligaments. The bony architecture of the knee is that of a modified hinge joint. The knee has three compartments - the inboard or medial compartment, the outboard or lateral compartment, and the compartment under the knee cap or the patellofemoral compartment. All three are lined by a thin layer of articular cartilage that help the knee move freely without friction. The knee is stabilized by important ligaments - the ACL (anterior cruciate ligament), the PCL (posterior cruciate ligament), the MCL (medial collateral ligament), the LCL (the lateral collateral ligament), and the PLC (posterolateral corner). There are two pieces of fibrocartilage called the meniscus - the medial and lateral meniscus - that help absorb shock, and lubricate the knee joint. Several tendons traverse the knee joint such as the quadriceps and patellar tendons. An injury to any one of these systems can lead to knee pain and dysfunction. Learn more about the conditions that Dr. Seneviratne treats in the following sections.