Though knee injuries are not commonly associated with auto accidents, many people have hurt their knee in a crash. Without healthy knees, walking and many other actions victims once took for granted may no longer be possible.

As WebMD explains, the knee is a complex joint, made of three parts: the femur, the tibia and the patella, also known as the thigh bone, the large shin bone and the kneecap. The femur and tibia meet to form the main joint, and the patella joins the femur, creating the patellofemoral joint.

Ligaments connect the inside and outside of the knee and cross within the joint, giving the knee stability and strength. To keep the two knee joints from bumping against each other, a cartilage pad called the meniscus provides cushioning as the knee moves.

The knee also includes tendons and bursae, or fluid-filled sacs. Damage to any of these parts can affect the knee’s ability to flex or bear weight — in other words, walk.

Relatively minor ligament injuries can be treated with rest, immobilization, ice packs and elevation. The victim may need to keep weight off the affected knee, which could mean using crutches until the ligament heals.

More serious injuries require surgery. Knee surgery can be done arthroscopically in some cases, while other patients must undergo open surgery. Surgical options include suturing or grafting the damaged ligament, or repairing it synthetically.

From the patient’s perspective, the goal is to eliminate or reduce the pain in their knee, and regain mobility and strength in the joint. This can be a long, difficult process, one that the responsible party should have to pay for, if the injury was reasonably preventable.