The knee is a common site for injuries. The tendons, ligaments, cartilage and bones of the knee are subjected to forces when running, jumping, twisting and kicking and also can be injured during a fall or direct blow. The ACL, or anterior cruciate ligament, and meniscus are common structures that can tear or become damaged. If you have an injury to the ACL or meniscus or are at a high risk of developing one, your best defense is to learn about these common injuries and how to prevent and treat them.
Introduction
The knee, where the thigh bones and lower leg bones meet, is a complex joint. The cartilage between the bones is called meniscus, and it helps cushion the joint so the bones do not rub against one another. Your knee also contains ligaments that connect bone to bone. The ACL is a ligament that limits forward motion and rotation of the lower leg bone to help stabilize the knee. There are also collateral ligaments that restrict sideways movements. The job of the ligaments is to prevent injury by preventing the joint from moving too far in any one direction.
Causes
Due to all of the movements the knee is subjected to, both the ACL and meniscus are prone to injury. The ACL can be stretched too far or torn. According to the Mayo Clinic, ACL injuries are most common during fitness and sporting activities. Twisting too fast with the feet planted, abrupt starting and stopping movements, hyper-extending the knee and quick directional changes can place too much force on the ligament, which can cause it to tear. All of these same movements also can lead to a tear in the meniscus. Sometimes, these two injuries occur simultaneously. Arthritic or degenerative changes to the knee can cause these structures to tear as well.
Symptoms
ACL and meniscus tears may be accompanied by a popping sound or sensation when the injury happens. The initial pain may not be severe enough to stop activity; however, without treatment, the pain will continue to get worse. It may be accompanied by swelling, a catching or locking sensation in the knee and feeling as though the knee is not stable. There may be a loss of strength and range of motion. The longer the knee is used when injured, the more severe the injury becomes and the longer it will take to heal. It is important to seek treatment for knee pain as soon as it starts to help avoid complications and lengthy recovery times.
Treatment
Proper diagnosis involves a physical examination, a review of symptoms, X-rays, MRIs and blood work to determine the exact injury and the extent of the tear(s). In the early stages, rest, ice and compression may be necessary until symptoms subside. If there are partial tears and the symptoms are not severe, the American Academy of Orthopaedic Surgeons recommends a period of physical therapy and rehabilitation exercises. The goal is to stretch and strengthen the muscles around the knee joint to help improve mobility and stability. Using a knee brace may also help. A physical therapist or coach can also teach proper body mechanics and ways of moving that do not stress the knee joint as much.
The time it takes to heal depends on the severity of the tear and each individual's fitness and goals. With both ACL and meniscus tears, if the injury is severe and does not respond to conservative treatment, surgery will be necessary. The type of surgery performed will depend on the extent of the injury and the level of activity that the patient wishes to return to.
Prevention/Solution
To help prevent ACL or meniscus injuries from occurring or reoccurring, it is important to train correctly and keep the muscles around the knee strong and flexible. Perform a proper warm-up and cool down before all activities, and wear the right footwear for your activity. If any activity causes knee pain, talk with a qualified coach or trainer who can suggest ways to move while taking pressure off the knee. Cross-training, doing variety of activities, also will keep the knees healthy. Strengthening and stretching the quads, hamstrings, inner and outer thighs and calf muscles will help take pressure off the knee. Perform strength training workouts two to three days per week, working each major muscle group to fatigue. Stretch daily to keep the muscles loose.
