Anatomy of the Knee | Knee Pain Treatment in Seattle
As the largest joint in the body, the knee is involved in a number of everyday activities. Athletes playing running sports rely heavily on their knees to move across the field, while less active patients rely on the knees for support when standing or walking.
Because the knees bear a significant amount of the body's weight during a number of routine activities, the joint is susceptible to damage through wear-and-tear and overuse. Common conditions affecting the knee include ligament tears, cartilage tears, and osteoarthritis, a degenerative wear-and-tear condition. These conditions can all cause pain, inflammation, joint stiffness, and limited range of motion in affected patients.
Understanding the knee’s structure and anatomy may help patients better understand the source of their knee pain. Continue reading to learn about the components of the knee, or schedule an appointment at Dr. Pritchett’s Seattle, WA offices to discuss treatment options for knee pain.
The Bones of the Knee
As a hinge joint, the knee is comprised of three main bones: the femur, or thighbone, the tibia, or shinbone, and the patella, or kneecap. The femur is the longest bone in the body, while the tibia is the second longest bone. The top of the tibia meets the bottom of the femur to form the main joint, also known as the tibiofemoral joint, with the patella attaching at the front, called the patellofemoral joint.
Patients with arthritis will experience bone damage due to natural degeneration. This condition worsens over time, and can cause significant pain and limit a patient's movement. Learn more about arthritis and how to treat the condition.
To prevent damage due to friction, the ends of the bones are covered with a smooth, white layer of cartilage. As the bones articulate, or move against one another, this fibrous tissue allows the joint to move freely without being damaged. This cartilage is lubricated by synovial fluid, a viscous and sticky material that gives the bones a smooth surface to slide against.
Two additional pieces of cartilage rest between the femur and the tibia called the menisci. These pieces of cartilage are soft and jellylike, providing additional protection against routine movement. The menisci acts as shock absorbers as weight is applied to the joint, and also help stabilize the knee during motion.
Injuries to the meniscus are very common, and can cause significant pain and limited range of motion. These injuries can occur when patients place too much stress on the knee, causing the meniscus to tear. Meniscal tears are also common in sports, and occur when a patient plants the foot and twists the knee. Over time, a torn meniscus can contribute to more serious joint damage, including onset of osteoarthritis.
The Four Ligaments of the Knee
The knee features four ligaments that attach bones to one another and provide stability. Two ligaments attach to the outside of the knee (collateral ligaments) while two attach from the inside (cruciate ligaments). All four ligaments help ensure that the knee moves safely within its natural range of motion by structuring movement. The collateral ligaments prevent the tibia from moving too far laterally, while the cruciate ligaments prevent the tibia from swinging too far forward or backward.
If the knee is pulled too far beyond its range of motion, these thick tendons can snap, causing immense pain, immobility, and joint swelling. Patients experiencing a ligament tear may hear a "pop" at the time of the injury, with the knee swelling soon after. Because ligaments lack a significant amount of blood flow, natural regeneration is uncommon, and surgery is often recommended.
Before diagnosing a knee injury, it is best to see an orthopedic surgeon specializing in knee pain treatment, who can best assess the condition. Dr. James W. Pritchett is one of Seattle's leading knee surgeons, and specializes in traditional total knee replacement and sports medicine, as well as innovative procedures including minimally invasive knee replacement, robotic assisted knee surgery, and cruciate retaining knee replacement.
Schedule an appointment with Dr. Pritchett to learn more about various knee pain treatment options for patients with osteoarthritis, ligament injuries, or cartilage damage.
Last Modified: July 30, 2014