Medical Reports: Knee

Anatomy and Function of the Knee Joint

The knee joint is one of the most burdened and functionally important joints in the human body. It is primarily composed of three main bones: the femur (thighbone), tibia (shinbone), and patella (kneecap). These bones are interconnected through a system of menisci, ligaments, and muscles that provide stability to the joint and allow for a variety of movements.

Key Components of the Knee Joint

• Cartilage: This smooth, elastic tissue cushions the contact surfaces between bones, reduces friction, and prevents bone wear during various activities.
• Meniscus: Each knee has two menisci, the medial and lateral. These C-shaped cartilage discs act as shock absorbers, cushioning impacts during intense or sudden movements like jumping or running. They also help distribute body weight evenly across the joint.
• Ligaments: The knee joint is stabilized by several strong ligaments, including the anterior cruciate ligament (ACL), posterior cruciate ligament (PCL), medial collateral ligament (MCL), and lateral collateral ligament (LCL). These ligaments prevent uncontrolled movement of the femur relative to the tibia, protect the joint from injuries, and help maintain proper alignment.
• Muscles and Tendons: Several muscle groups work around the knee, including the quadriceps at the front of the thigh and the hamstrings at the back. These muscles are connected to bones through tendons, transmitting the force of muscle contraction to the bones, enabling movement, and helping stabilize the knee during motion.

Functions of the Knee Joint

• Movement: The knee joint allows for bending (flexion), straightening (extension), and, to a limited extent, rotation.
• Weight Support: The knee is not only crucial for movement but also bears a significant portion of the body’s weight, especially in a standing position or when shifting weight from one leg to the other.

Understanding these key anatomical and functional aspects helps us better comprehend how injuries and illnesses can affect our daily movements.

Common Knee Injuries and Conditions

The knee joint is often exposed to various injuries and conditions. These can result from acute trauma, wear and tear due to repetitive movements, or degenerative conditions.

Acute Injuries

• Knee Sprain: Often occurs when the knee suddenly twists in an unnatural direction, potentially damaging the ligaments. Knee sprains are common in sports such as soccer, basketball, and skiing, where quick turns and jumps place high demands on the ligament system.
• Meniscus Injuries: The meniscus can be injured by a sudden twist of the knee while the foot is fixed on the ground. This is common when lifting heavy weights or during sports activities that require rapid changes of direction. A meniscus injury causes pain, swelling, and difficulty fully bending or extending the leg.
• Ligament Injuries: The anterior cruciate ligament (ACL) is one of the most stressed ligaments in the knee and is frequently injured. ACL injuries can occur when an athlete suddenly stops, changes direction, or receives a strong blow to the front of the knee. Symptoms include sharp pain, a loud pop, immediate swelling, and significant knee instability.

Degenerative Conditions

• Osteoarthritis: The most common form of arthritis affecting the knee is caused by cartilage wear and tear. Symptoms include pain, stiffness, and reduced joint mobility, which typically worsen with age. Osteoarthritis develops gradually and often affects older individuals, especially those with higher body weight or a history of knee injuries.
• Tendinitis: Inflammation or irritation of tendons, often due to overuse, especially in runners and cyclists. Patellar tendinitis (jumper’s knee) is an example of tendinitis that affects the lower part of the knee, causing pain just below the kneecap, particularly during activities involving frequent knee bending, such as jumping and running.

Chronic and Systemic Conditions

• Rheumatoid Arthritis: This autoimmune condition causes chronic inflammation of multiple joints, including the knees. It can result in pain and joint deformity. The disease is characterized by cyclical symptoms, which may include fatigue, weight loss, and symmetrical joint inflammation.
• Bursitis: Inflammation of the bursae, small fluid-filled sacs that cushion friction between tissues. Knee bursitis is common in occupations that require prolonged kneeling, such as paving, gardening, and certain sports. Symptoms include pain, swelling, and tenderness in the affected area.

Due to the complexity of the knee joint and the variety of possible injuries and conditions, understanding the symptoms and early recognition of problems is crucial.
Early detection and treatment can prevent long-term damage and improve quality of life.

Diagnostic Procedures for Knee Problems

Accurate diagnosis is the foundation of effective treatment for knee injuries and conditions. Physicians use several diagnostic techniques to determine the exact cause of symptoms and identify the most effective treatment method.

Physical Examination

The physical examination is the first step in diagnosing knee problems. The physician will thoroughly examine the knee for swelling, pain, warmth, and deformities. Special attention will be given to comparing it with the healthy knee on the opposite leg. During the examination, the doctor will assess joint mobility, ligament stability, and the presence of fluid in the joint, which may indicate inflammation or injury.

Imaging Diagnostics

• X-rays: This basic method is used to visualize the condition of bones and joints. X-rays are particularly useful for identifying fractures, arthritis, or other structural changes in the knee, such as joint misalignment or signs of wear and tear.
• Magnetic Resonance Imaging (MRI): This method is highly accurate in evaluating soft tissues such as menisci, ligaments, and cartilage. It provides detailed three-dimensional images of the knee's internal structure, making it essential for diagnosing complex injuries like ligament or meniscus tears and assessing the extent of damage.
• Ultrasound: Ultrasound imaging is often used to examine the condition of tendons, bursae, and other soft tissues around the knee. This technique is particularly useful for guiding medical procedures, such as injections to reduce inflammation or aspiration of joint fluid, allowing for precise targeting of affected areas.

Laboratory Tests

Laboratory tests are ordered when a physician suspects infectious or autoimmune causes of knee pain. Blood tests can reveal markers of inflammation, such as C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR), aiding in diagnosing conditions like rheumatoid arthritis. Joint fluid analysis is crucial for identifying infection-causing agents or the presence of gout crystals.

Arthroscopy

Arthroscopy allows physicians to directly examine the inside of the knee joint. This minimally invasive procedure involves inserting a thin camera through a small incision in the skin, enabling a visual inspection of the cartilage, meniscus, and ligaments. Arthroscopy can be used for diagnostic purposes or to perform minor surgical repairs within the joint.

Explanation of Common Medical Terms Related to Knee Problems

To better understand your medical reports and potential knee-related diagnoses, here is a closer look at some common medical terms:

• Gonarthrosis: Another term for knee osteoarthritis, a type of arthritis that causes cartilage wear in the knee joint.
• Chondromalacia patellae: Softening of the cartilage on the back of the kneecap, which can lead to pain and movement issues.
• Patellar fracture: An injury where the kneecap breaks, usually caused by a direct impact or a strong contraction of the quadriceps.
• Medial collateral ligament (MCL) rupture: An injury where the ligament on the inner side of the knee is partially or completely torn.
• Lateral collateral ligament (LCL) rupture: An injury where the ligament on the outer side of the knee is partially or completely torn.
• Parapatellar/Infrapatellar Plica Resection: A surgical procedure to remove tissue around the knee that may cause pain or hinder movement.
• Proliferative Enthesopathy of the Patellar Ligament: A condition involving inflammation and pain at the attachment site of the patellar ligament to the bone, often caused by repetitive stress.
• Patella alta: A condition where the kneecap is abnormally positioned high, affecting its movement and causing pain.
• Meniscus incarceration: A condition where part of the meniscus becomes trapped between the knee bones, causing pain and restricted movement.
• Chondropathy: A general term referring to any cartilage disease, including degeneration or injury.
• Anterior Cruciate Ligament (ACL): A ligament that prevents excessive forward movement of the tibia relative to the femur and is essential for stability during rotational movements. It is commonly injured during sports activities.
• Posterior Cruciate Ligament (PCL): A ligament that prevents excessive backward movement of the tibia relative to the femur and ensures knee joint stability.

These conditions collectively help in understanding the various mechanisms of injuries, possible diseases, and treatment methods that are essential for maintaining the function and health of the knee joint.

Treatment Options and Recovery for Knee Problems

Once a diagnosis is made, the choice of appropriate treatment depends on several factors, including the type and severity of the injury or condition, the patient’s age, overall health status, and lifestyle. Treatment may include a range of methods, from conservative approaches to invasive surgical procedures.

Conservative Methods

• Rest and Protection of the Knee: Temporarily reducing or stopping activities that cause pain or further damage to the knee is crucial. Using braces or crutches can help reduce stress on the knee, accelerating the healing process.
• Physiotherapy: Physiotherapy programs are designed to improve joint mobility, strengthen the muscles around the knee, and enhance overall functionality. Techniques such as ultrasound for deep heat therapy, electrotherapy for pain relief, and ice packs to reduce inflammation are often part of the therapy plan.
• Medications: The use of anti-inflammatory drugs helps manage pain and inflammation. For more intense pain or inflammation, corticosteroid injections may be used to provide rapid symptom relief, although their long-term use is limited due to potential side effects.

Medical and Surgical Procedures

• Arthroscopic Surgery: This minimally invasive technique is used to diagnose and treat internal knee problems such as meniscus, cartilage, or ligament injuries. During this procedure, the doctor makes small incisions and uses specialized cameras and instruments to repair damaged structures.
• Knee Joint Replacement (Arthroplasty): In cases of advanced osteoarthritis or severe injury where other methods fail to provide relief, knee joint replacement may be performed. This surgical procedure replaces the damaged parts of the joint with artificial implants, often restoring mobility and improving quality of life.
• Osteotomy: This surgical procedure is used to realign the leg to reduce stress on the damaged part of the knee. It is particularly suitable for younger patients where joint replacement is not yet appropriate and can significantly delay the need for a joint replacement.

Rehabilitation and Recovery

The rehabilitation process following knee injury treatment is extensive and requires close cooperation between the patient and the medical team. Rehabilitation includes continued physiotherapy, regular check-ups, and lifestyle adjustments such as regular exercise and maintaining a healthy weight to reduce additional stress on the knees. Patients should pay attention to symptoms that indicate potential complications or recurrent injuries and respond promptly by consulting a doctor.

A properly managed rehabilitation plan is crucial for successful recovery and can significantly increase the likelihood of the patient returning to normal activities without long-term issues.