By Elena Voropay

Got a serious knee problem – get ready to put your life on hold. It can interfere with every single activity of daily living, from simply getting up from a chair and walking, to losing sleep and muscle mass. The knee is the joint where the bones of the upper leg meet the bones of the lower leg, allowing hinge-like movement while providing stability and strength to support the weight of the body. Flexibility, strength, and stability are needed for standing and for motions like walking, running, crouching, jumping, and turning.

Knee Joint and ACL

Ever had trouble opening or closing a tight door while hearing a squeaking noise? Pretty annoying, isn't it. Well, this is the way your knee feels when it is injured. The structure of the knee joint resembles that of a door – your upper leg bone, or femur, is the solid wall, your lower leg bone, or tibia, is the moving door, and the hinge keeping these two together is your patella. The weight-bearing surface of the knee is covered by a layer of articular cartilage. On either side of the joint, between the cartilage surfaces of the femur and tibia, are the medial and lateral meniscus. These team up with cartilage and act as shock absorbers reducing the impact you put on your leg bones with every step you take. between the tibia and the femur.

The hinged knee joint is held together by the four “screws” - medial collateral ligament (MCL), lateral collateral ligament (LCL), anterior cruciate ligament (ACL) and posterior cruciate ligament (PCL). So, the ACL is one of the four main ligaments within the knee which connects the femur to the tibia. But unlike the medial and lateral connecting tissues which go straight down, ACL runs diagonally in the front and middle of the knee preventing the tibia from sliding out. Another significance of Anterior Cruciate Ligament is to give the knee rotational stability. Thank your ACL for letting you do all kinds of squats and leg presses – toes forward or toes out.

Causes of ACL Injury

Even though the ACL is the smallest of the four main ligaments, it is the primary stabilizer. Maybe that is the reason this soft tissue is the most commonly injured knee part. Very common in sports that require acceleration, change of direction and deceleration, knee injuries are a common thing in every day living. Did you that 70 percent of ACL injuries occur through non-contact mechanisms while only 30 percent result from direct contact with another player or object? If you are a rugby or football player, this fact may ease your mind. But if you are a bodybuilder, the harsh truth stays within your body.

Since every muscle-busting activity you do in the gym doesn't require hitting your workout buddies around, the mechanism of an ACL tear is easier to relate to your iron-pumping work. ACL injury is often associated with slow movement coupled with cutting, pivoting or sidestepping. So, every time you push your body with legs against resistance, such as in leg press, squat, lunge, or any other exercise, you have a chance for awkward foot position.

Have you ever dreamed of being a woman? Whatever comes to your mind right now or any other time is not the subject of discussion here, but there is a knee issue that relates to women. Female athletes have a higher incidence of ACL injury than male athletes due to differences in physical conditioning, muscular strength, and neuromuscular control. Thanks to women's in-born gift of the expected child-bearing, their pelvis and lower extremity (leg) alignment is also naturally different than that in men. Women have a slightly smaller ACL, on average, and the place where the ACL passes through the knee joint, the intercondylar notch, is slightly smaller as well. Add to that an increased ligamentous laxity and the relaxing effects of estrogen on ligament properties, and you have an explanation why women complain of their joint problems, among millions of others, more often. This is your chance to give the feminine nature some credit for their endurance and resistance to pain.

When an ACL injury occurs, the knee becomes less stable, and that is a big problem for any type of movement involving the leg. Not only that, having a hurt knee increases your chances of getting other ailments, such as poor walking technique, bad posture, back and neck problems, and serve as a good foundation for arthritis of the knee, meniscus and cartilage tears. Note that half of ACL injuries occur in combination with damage to the meniscus, articular cartilage, or other ligaments. So, if you damage the knee, get ready to master the anatomy and physiology of the joint through a first-hand painful experience.

Symptoms of ACL Injury

Your ACL is thin, but quite strong – it can support a force of 1700 N (newtons) before complete failure. But the injury doesn't follow all-or-none principle, and can be partially torn, strained or overstretched. All of these cause pain, inflammation, instability and may precede the development of other unwanted ailments.

When an Anterior Cruciate Ligament ruptures or tears, you may:

• Hear a pop from the inside of the knee.
  
• Feel the knee snap out and back into place. See the knee turning into a small balloon immediately, or within a few hours after the injury.
  
• Feel pain, unless you take hard-core painkillers on a regular basis
  

After an examination by your primary care physician, he or she may refer you to an Orthopaedic surgeon, or Orthopaedist, who specializes in nonsurgical and surgical treatment of bones, joints, and soft tissues such as ligaments, tendons, and muscles.

You may also be referred to a Physiatrist who knows more than a thing or two about physical medicine and rehabilitation. Both knee professionals will help you restore optimal function of the hurt joint. After a thorough examination, the doc may perform several special tests to see whether the parts of the knee stay in proper position by applying pressure from different directions, such as Lachman's Test or the Pivot Shift Test. These will help your healing assistant pinpoint the exact condition of the ACL – torn completely, partially, or not at all. You may have to get an MRI for accurate reading.

If it is a complete tear, you are in the hands of your faith. You may not be able to function in your normal daily activities without a normal ACL, so undergoing surgery shouldn't be debated. The surgeon may reconstruct torn ligament by using a graft of healthy tissue from your own body, known as autograft, or from a the body some unknown generous donator, known as allograft. Although synthetic ligaments have been tried in experiments, the results have not been as good as with human tissue. Be prepared for a loss of full range of motion, pain or tenderness along the joint line and discomfort while walking immediately after surgery.

If your ACL is only partially teared, which isn't great to begin with, but much better than the complete tear, you may recovery in 2-3 months time. But to get in shape that fast, you have to follow all the complicated rehabilitation techniques, close clinical follow-up and a religious dedication to a complete course of physical therapy. One word of warning in any type of knee injury - some patients with partial ACL tears may still have instability symptoms.

For an incomplete tear, the doctor may recommend an exercise program to strengthen surrounding muscles. You may also be prescribed to wear a brace to protect the knee during activity. You will find that many recovery and rehabilitation suggestions correlate with stretching and strengthening exercises used in preventing ACL injury.

Prevention of ACL Injury

As with all injuries, the best way to handle ACLs is not to hurt them. If you follow common sense, write down the following tips and stick them on your fridge and into your training dairy, then put the protection of your joints on top of all workout priorities, your healthy knees are guaranteed.

1. Before exercising or participating in sports, warm up by walking or riding a stationary bicycle, then do stretches. The warm up before stretching is very important and will help improve range of motion, reduce stiffness and muscle soreness, improve overall mobility and performance.
   
2. Stretching will keep the muscles and tendons flexible, so they can absorb shock better. Stretching the muscles in the front of the thigh (quadriceps) and back of the thigh (hamstrings) reduces tension on the tendons and relieves pressure on the knee during activity. Remember the magic six stretches for legs: Calves, Hamstrings, Quadriceps, Hip Flexors, Adductors and Abductors (or inner and outer thighs).
3. Wear shoes that both fit properly and are in good condition to maintain balance and leg alignment at all times, whether you walk, run, squat or simply stand in place. If you feet are flat or overpronated that roll inward, you increase your risk of all sorts of knee injuries. You may help reduce some of these problems by wearing special shoe inserts (orthotics) and ensure good fitting.
4. Strengthen the leg muscles by walking up stairs or hills, riding a bicycle, and incorporating walking lunges, hamstring curls, leg extensions, and toe raises into every leg workout. One thing of caution – when you do squats and leg presses, watch your form and check the entire body and knee alignment.
5. Avoid sudden changes in the intensity of exercise. Increase the force or duration of activity gradually. Improving leg strength is a sure way for a more stable knee joint. Technique is everything; close attention must be paid to the performance of these exercises in order to avoid injury.
6. Plyometric exercises may be excellent for your knees, but only if these joints are healthy and strong to begin with. Squat-jumps, Scissor-jumps, Single-leg hops, Lateral hops and Forward-backward jumping lunges will help you to build power, strength and speed. The most important element during plyometrics is the soft landing on the balls of your feet and slow rolling back to the heel. Remember to keep knees bent and hips straight.
7. Add the following joint-supporting supplements to your regular mountain of pills and powders: Glucosamine, Chondroitin Sulfate, MSM (Methyl Sulfonyl Methane), Hydrolyzed Collagen Protein (Gelatin), and Omega-3 fatty acids.

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