The lateral collateral ligament (LCL) is a ligament located inside the knee joint. Ligaments are thick, strong bands of tissue that are connected bone to another bone. The LCL runs through the outside of the knee joint, from the outside of the bottom of the thighbone (femur) into the top of the lower leg bone (fibula). The LCL supports the knee joint with great stability, mainly in the outer aspect of the joint. An injury to the LCL may include straining, spraining, and partially or completely tearing any location of the ligament. Studied by many doctors, it is proved that the LCL is one of the more commonly injured ligaments in the knee. Due to the location of the LCL, it is often to injure the specified ligament along with others in the knee.
Anatomically, The LCL is a cord-like structure of the accurate ligament complex, bonded with the biceps femoral, tendon, popliteus muscle, popliteal meniscal, and lateral gastrocnemius muscle. This specific ligament is a powerful connection between the lateral epicondyle of the femur and the head of the fibula, with the function to avoid varus stress on the knee and tibial external rotation and a stabilizer of the knee. Whenever the knee is flexed to more than 30 degrees, the LCL is then loose. The ligament is strained when the knee is in extension.
Lateral collateral ligament sprain injuries are classified into three grades depending on severity. The following include:
Grade 1: Mild Sprain
- Mild tenderness and pain over the lateral collateral ligament.
- Usually no swelling.
- The varus test in 30 degrees is painful although does not show any type of laxity (<5mm laxity).
- No instability or mechanical symptoms present at the moment.
Grade 2: Partial Tear
- Significant tenderness and pain on the lateral and posterolateral side of the injured knee.
- Swelling in the area of the ligament.
- The varus test is painful and there is laxity located in the joint with a clear endpoint. (5-10mm log laxity)
Grade 3: Complete Tear
- The pain may vary and can be less than grade 2 LCL partial tear.
- Tenderness and pain at the lateral side of the injured knee and at the injury.
- The varus test shows a significant joint laxity (>10mm laxity).
- Subjective instability.
- Constant swelling.
Patients who are injured by an acute LCL will often attend with a history of an acute incident which most likely consisted of a blow to the medial part of the knee meanwhile in full extensions or extreme contact varus bending. As to the pain, swelling and ecchymosis are active at the lateral joint line including a great difficulty in full weight-bearing. Patients who are injured by a sub-acute lateral collateral ligament sprain will present with lateral knee pain, stiffness with an end of range flexion or extension, totaling weakness, and a possibility of instability.
Who Gets LCL Strains?
Collateral ligament knee sprain injuries make up about 25% of severe knee injuries in the United States. They can occur more often in adults aged 20 to 34 years and from 55 to 65 years. Lateral collateral ligament sprains mainly happen during sporting activities, including contact and non-contact sports. This type of injury can affect both women and men equally. Physical therapists treat patients with LCL sprain to help reduce pain, swelling, stiffness, and any related weakness located in the affected knee or lower severity. As mentioned earlier, the lateral collateral ligament can be injured or torn during contact sports, such as football and hockey, or sports that heavily involve quickly turning or changing direction, such as soccer and basketball. LCL injuries are commonly reported after the following situations:
- An instant blow against the inside of the located knee, such as during a football tackle.
- Changing directions rapidly or by pivoting on one foot, such as in soccer or basketball.
- Landing improperly from a jump, such as during volleyball or basketball.
Many people who enjoy this type of productivity may also note an instability inside their knee, especially with side-to-side or pivoting activities.
Isolated collateral ligament injuries are also rare in adolescent athletes. Medial collateral ligament injuries, one-quarter that occurred in conjunction with patella instability events, were 4 times more common rather than lateral collateral ligament sprain injuries, one-quarter of which have other posterolateral corner structures involved. Grade 3 tear injuries represent 20% to 25% of collateral ligament injuries and occurred most commonly in sports such as mentioned above.
How Does It Affect You? How Serious Is It?
For the minor type of injuries, the LCL may heal without any issue. However, it is important to understand that if the ligament has harshly stretched, it may never regain its usual stability. This means that it is more likely that the injured knee will be somewhat unstable and a patient could easily injure it once again. The joint could become swollen and sore simply from any sporting activity or minor injury.
Now for those with a major injury of the LCL who do not have surgery, the joint will most likely remain unstable and easily injured. The person may not be able to perform any physical activities that require repetitive use of the injured knee, including running, climbing, or biking. Pain could result from minor activities such as walking or standing for an extended period of time. He or she may have to wear a brace to protect the joint from further pain during physical activities. That being said, for patients who have surgery, the outlook will then depend on the severity of the original injury and the surgical procedure. Generally, a surgically treated patient will have improved mobility and stability after the joint completely heals. People will have to wear a brace or limit physical activities in the near future to help prevent re-injuring the affected knee. Surgery is extremely rare in the case of LCL sprains. Although, if an individual has an LCL tear or injury to other parts of the knee at the same exact time, he/she may need additional treatment that might include surgery. After surgery, a recovery program will be followed over several weeks guided by a physical therapist. They will help minimize pain, regain motion, strength, and agility, and can finally return to activities in the safest and fastest manner possible. In knee injuries involving more than just the located LCL, treatment and outlook may become different, as those injuries could be more severe.
Recommended Treatment & Rehabilitation
Similar to medial collateral ligament sprain injury treatments, most LCL injuries can be treated at home with the following:
- Resting and protecting your knee.
- Ice or a cold pack.
- Wrapping your knee with an elastic bandage (compression).
- Propping up (elevating) your knee.
- Anti-inflammatory medicine.
Your doctor may suggest you use equipment such as crutches to limit how much weight you put onto your leg. He or she may also suggest you wear a brace that can protect and support the injured knee although allows room for some movement.
You may need to be less active for some time. However, fortunately, doing gentle stretching and range-of-motion exercises as advised by your physical therapist will help you heal faster. As mentioned earlier, a severe tear may need surgery. But this normally isn’t initiated unless you also injure other parts of your damaged knee. Mild or grade 1 injuries may only require home treatment alongside using crutches for a short time. You will also need to wear a hinged knee brace when your doctor states it is okay for you to add weight onto your injured leg. Many patients are able to become active again after about 3 to 4 weeks. Moderate or grade 2 injuries will require using crutches and wearing a hinged knee brace. Many people are able to be active again after 8 to 12 weeks. Severe or grade 3 injuries strongly require wearing a hinged brace for a few months, limiting weight on the leg for at least 6 weeks during recovery. In some cases, surgery may be needed. Most patients are able to return to activities again after 8 to 12 weeks.
As for a diagnosis of LCL sprain injuries, the doctor will examine you and ask questions about your past health. Afterward, he/she will also ask how you have injured your knee while asking about your symptoms at the time you injured your knee. Your doctor will then examine and observe your knee and leg. After a few minutes of observing, your doctor will feel to see if there is swelling and may gently push on some places to find spots that are mostly tender. Then your doctor will perform movements of your injured knee in certain ways to help check for stability. Finally, The doctor will visualize the rest of your leg to assure that blood is flowing well, as for the leg functioning positively, and there are no other types of injuries presented either above or below the knee. X-ray, an MRI, or an ultrasound test may be required during diagnosis.
Below are a few great at-home exercise methods for you to freely perform. These are guaranteed to reduce a huge amount of pain during the injured progression of lateral collateral ligament sprains:
Knee flexion with heel slide
Lie on your back with your knees well bent. Slide your heel back by bending your affected knee as far as you can. Then hook your other foot around your ankle to help pull your heel even farther back. Hold this position for about 6 seconds, then rest for up to 10 seconds. Repeat the same procedure 8 to 12 times.
Heel slides on a wall
Lie on the floor close enough to a wall so that you can then place both legs up to the desired wall. Your hips should be as close against the wall to the right comfort for you to perform the exercise. Begin the session by placing both feet, resting on the wall. Slowly let the foot of your injured leg slide down the wall until you feel a stretch in your knee. Hold this position for 15 to 30 seconds. Then slowly slide your foot up to where you began. Repeat this 2 to 4 times.
Sit with your injured leg straight and nicely supported on the floor or a firm bed. Place a tiny, rolled-up towel beneath your knee. Your opposite leg should be bent, with a floor mat placed on the floor. Tighten the thigh muscles of your injured leg by pressing the back of your knee down into the towel. Hold for 6 seconds, then rest for up to 10 seconds. Repeat the method 8 to 12 times.
Straight-leg raises to the front
Lie on your back with your good knee bent so that your foot can rest flat onto the floor. Your injured leg should be straight. Assure that your lower back has a usual curvature. You should then be able to slip your hand in between the floor and the small back, with your palm making contact with the floor and your back touching the back of your hand. Tighten the thigh muscles inside your injured leg by pressing the back of your knee flat down against the floor. Hold your knee straight. Keeping the thigh muscles tight as you keep your leg straight, finally lift your injured leg up so that your heel is about 30 centimeters off the floor. Hold this position for 6 seconds, then lower slowly afterward. Relax for up to 10 seconds between reps. Repeat the same method 8 to 12 times.