Anatomy of the knee: Two bones meet to form your knee joint: the thighbone (femur) and shinbone (tibia). Your kneecap sits in front of the joint to provide some protection. Bones are connected to other bones by ligaments. There are four primary ligaments in your knee. They act like strong, supportive ropes that help hold the bones together and keep your knee stable. Collateral Ligaments. These ligaments are found on the medial and lateral sides of your knee. The medial collateral ligament is on the inside, and the lateral collateral ligament is on the outside.
They are the ligaments which control the sideways motion of your knee and brace it against unusual movements. Cruciate Ligaments. These types of ligaments are found within the knee joint. They cross each other to form an “X” with the ACL (anterior cruciate ligament) and the PCL (posterior cruciate ligament) in the back. The cruciate ligaments control the forward and backward motions of the knee. The PCL keeps the tibia from hyperextending, or moving back too far. It is stronger than the ACL and is injured less often. The PCL has two parts that blend into one structure that is about the size of a person’s little finger.
Description: Injuries to the PCL are not as common as other ligament injuries in the knee and are usually more difficult to evaluate than other ligaments. Many times, PCL injuries occur along with injuries to other structures in the knee such as cartilage, other ligaments, and bone. Injured ligaments are considered “sprains” and are graded on a severity scale of 1-3 1. Grade 1 Sprains. The ligament is mildly damaged, slightly stretched, and is able to keep the knee stable. 2. Grade 2 Sprains. The ligament is stretched enough that it becomes loose. This is considered a partial tear of the ligament. 3. Grade 3 Sprain.
This type of sprain is often referred to as a complete tear of the ligament. The ligament has been split into two sections, and the knee joint then becomes unstable. Posterior Cruciate Ligament tears tend to be partial tears with the potential to heal on their own. People who have injured just their PCL are usually able to return to sports without stability problems but as stated earlier, PCL injuries often occur with the injury of other ligaments, tendons or bones. A complete tear of the PCL, posterior view. Causes: An injury to the posterior cruciate ligament can happen in many ways. It typically requires a powerful force in order to do so.
A direct blow to the front of the knee, forced hyperextension, such as a bent knee hitting a dashboard in a car crash, or a direct football tackle to the knee. Pulling or stretching the ligament, such as twisting or hyperextension. Or it could even happen by a simple misstep. The knee locks in too far and causes a slight stretch or tear depending on what the misstep was on and how long it lasted. Symptoms: The typical symptoms of a posterior cruciate ligament injury are: Pain with swelling that occurs steadily and quickly after the injury. Swelling that makes the knee stiff and may cause a limp. Difficulty walking.
“Unstable knee” feeling (giving out) How to check up for a PCL injury: X-rays. Although they will not show any injury to the PCL, x-rays can show whether the ligament tore a piece of bone when it was injured. This is called an avulsion fracture. MRI. This study creates better images or soft tissues like the posterior cruciate ligament Treatment: RICE. When an athlete is injured, the RICE method- rest, ice, compress, and elevate- can help speed up recovery. Immobilization. Your doctor may recommend a brace to prevent your knee from moving. To further protect your knee, you may be given crutches to keep you from putting weight on your leg.
Physical Therapy. Strengthening leg muscles in the thigh or quadriceps has been shown to be a successful recovery technique. Surgical Treatment: Rebuilding the ligament. Because sewing the ligament ends back together does not usually heal, a torn posterior cruciate ligament must be rebuilt. Your doctor will replace your torn ligament with a tissue graft. This graft is taken from another part of your body, or from another human donor. It can take several months for the graft to heal into your bone but is risky because the body may reject a skin graft from a donor.