The knee is the largest and most complex joint in the body, responsible for daily movement, making it vulnerable to injuries and recurrent discomfort. The knee is involved in many daily activities, especially for those who engage in regular sports. In this article, we explore common types of injuries, how to prevent them, and provide tips for knee care, with Dr. José Luis Castilla, a specialist in physical medicine and rehabilitation.
How the Knee Works: Movement and Stability
All components of the knee, including bones, muscles, ligaments, tendons, and cartilage, work together to provide the ideal movement necessary for bending and extending in a balanced and precise manner. This harmony between the different parts ensures that the knee can perform daily tasks such as walking, running, and climbing or descending stairs with stability and smoothness.
Flexion occurs when the quadriceps muscle in the front thigh relaxes, while the hamstring muscles in the back thigh contract. Extension happens when the opposite occurs: the quadriceps contract and the hamstring muscles relax.
Dr. Castilla explains, “The role of ligaments is to stabilize the joint and restrict unwanted movements, such as rotation. Meanwhile, the meniscal cartilage helps absorb shocks and distribute the weight of the bones during movement.” Thanks to this integrated cooperation, the knee can bear large weights and adapt to various movements like jumping and running.
Main Knee Injuries and Their Causes
“Knee injuries mainly depend on the age of the patient,” says Dr. Castilla. “In young people, they are often inflammatory, such as tendonitis, or traumatic, like injuries caused by sprains.” A knee sprain occurs due to ligament injury, often resulting from excessive stress on the joint due to a sudden twist or direct impact. Let’s take a look at the most common knee injuries and their causes.
Ligament Injuries: Sprains and Tears
There are two types of injuries that commonly affect the ligaments: anterior cruciate ligament (ACL) injury and medial collateral ligament (MCL) injury. These injuries occur due to ligament tears resulting from twisting or traumatic injury. These injuries commonly happen in sports that require sudden changes in direction or abrupt stops, such as football.
Meniscal Injuries: Tears and Symptoms
Meniscal injuries generally occur due to traumatic injury, often happening in young athletes who perform a sudden knee rotation or suffer a blow to the area. A tear is common in these cases. The main symptoms of this injury include sharp pain when rotating the knee, stiffness, and swelling in the region.
“As we age, due to age-related changes, degenerative injuries to the meniscus may arise. While not traumatic injuries, these can lead to meniscus tears,” adds Dr. Castilla. “This is especially true for individuals who engage in activities requiring climbing and descending stairs, which can put high pressure on the joint.”
Patellar Tendonitis: Pain in the Front of the Knee
Patellar tendonitis, also known as jumper’s knee, is common in sports such as basketball or volleyball. It occurs due to injury to the tendon that connects the patella to the tibia, responsible for extending the knee for jumping and running.
Bursitis in the Knee: Inflammation of the Bursae
Bursitis is the inflammation of the small fluid-filled sacs near the knee joint, known as bursae, which help reduce friction and absorb pressure. It can lead to pain and limit knee flexibility.
Knee Cartilage Degeneration: Cartilage Wear
The wear of cartilage in the back of the knee leads to cartilage degeneration. It causes pain, usually in the front part of the knee, and mainly affects athletes, as they may sometimes feel bone friction when bending the knee.
Arthritis and Osteoarthritis in the Knee: Chronic Pain and Cartilage Degradation
As we age, Dr. Castilla explains, “degenerative injuries caused by osteoarthritis appear,” which is a condition caused by the gradual degradation of cartilage. On the other hand, we may also encounter rheumatoid arthritis in older adults, which is an autoimmune disease that can affect any joint. Both conditions cause persistent knee pain, joint swelling, and varying levels of pain intensity.
Knee Injury Symptoms: When Should You Worry?
Knee pain primarily depends on the cause and the speed at which symptoms appear. Symptoms can show suddenly after a blow, as in sports, or gradually when related to a condition in older age.
Pain, swelling, and stiffness: Early warning signs
The first symptoms of an injury are typically swelling, redness, or an increase in temperature, in addition to pain. Depending on the severity and cause of the injury, a person may feel that the knee is unstable or that it limits movement, making it difficult to fully extend.
Instability, Joint Sounds, and Movement Restrictions: How Do I Know if the Knee Injury is Severe?
The severity and type of injury, along with the patient’s age, determine certain signs that may indicate whether the injury is serious or not. It’s best to consult a doctor if you notice any of the following symptoms:
- Inability to bear weight on the knee.
- Instability or significant weakness.
- Crackling or friction sensation when moving the knee.
- Inability to fully extend or bend the joint.
- Deformity or swelling in the knee.
- Presence of fever along with numbness.
- Increased pain after the impact or if it persists without improvement.
How to Care for Your Joints?
While it’s completely difficult to eliminate any pain or injury entirely, since the causes can be multiple, there are some guidelines we can apply in our lifestyle to support the well-being of our joints, such as the knee. Dr. Castilla recommends the following:
- Maintain a healthy weight: Excess weight can increase the risk of joint injuries and diseases, especially in the knee.
- Warm up before exercise and stretch afterward: It’s essential to do a proper warm-up before physical activity to prepare the body and reduce injury chances. Cooling down with stretching helps relieve muscle tension and promotes recovery.
- Strengthen leg muscles: Muscle weakness is a common cause of knee injuries. It’s important to strengthen the quadriceps and hamstring muscles, as well as perform exercises to improve balance and stability.
- Wear proper shoes and use correct techniques during sports: Shoes should be comfortable and appropriate for the sport. They need to fit the specific activity you’re doing and provide proper support.
- Adapt exercise to personal limitations: If you have recurring pain or injuries, reduce high-impact activities and follow the doctor’s instructions to avoid exacerbating injuries.
Nutrition and Supplements for Joint Health
Balanced nutrition
“Healthy and balanced nutrition is essential for the health of bones and muscles,” says Dr. Castilla. “However, it’s common to engage in high-intensity sports, which can cause wear and tear on the joints.” There are certain nutrients that can be beneficial in this area, helping to maintain the skeletal system in optimal condition.
Glucosamine and Chondroitin
Glucosamine and chondroitin are naturally found in our bodies, especially in cartilage structures, where they enhance flexibility. They can be found in supplements aimed at supporting bone and joint health in the form of glucosamine sulfate and chondroitin sulfate.
Collagen
Collagen is a protein naturally present in the body and is a key part of the joints, skin, cartilage, and connective tissues. As we age, the body’s collagen reserves decrease, making it important to add it to the diet.
Magnesium and Calcium
Calcium is found in over 90% of the skeleton and is crucial for bone formation, in addition to supporting bone mineralization and its relationship with bone density. Magnesium plays a major role in maintaining bones and muscle function. It is primarily stored in the bones, with the rest in active tissues such as muscles.
Vitamins
Vitamin C contributes to the formation of natural collagen for the function of bones and cartilage. Vitamin D helps maintain bones in good condition as it is closely linked to calcium supply, aiding its absorption and utilization. Vitamin K2 also helps maintain healthy bones.
Turmeric
Widely used in Eastern cultures, turmeric contains the key active ingredient curcumin. Turmeric helps reduce inflammation in joints and muscles.
