1. Symptoms of Muscle Pain Behind the Knee

Statistics show that more than 10% of middle-aged people experience pain behind the knee. Recognizing the basic symptoms of this condition can help patients detect it early.

1.1. Pain Behind the Knee

The most typical symptom is pain located at the back of the knee. The pain may be dull or sharp and often worsens with movement, making daily activities difficult.

1.2. Knee Swelling

Swelling around the knee is visible to the naked eye. This occurs due to fluid buildup inside or around the joint, often accompanied by warmth in the knee.

1.3. Knee Stiffness

Knee stiffness, especially in the morning, is another common sign. Patients may find it difficult to lift the leg or perform normal movements.

1.4. Grinding or Cracking Sounds

Loose cartilage caused by muscle pain behind the knee may lead to abnormal joint sounds. Patients may hear grinding or cracking noises, particularly when climbing stairs.

1.5. Weak Knees

As the condition progresses, the knee becomes weaker. Numbness in the legs may also occur.

1.6. Knee Buckling

Injury-related muscle pain can damage cartilage in the front, back, or middle of the knee. Prolonged damage may lead to knee buckling and deformity.

Other accompanying symptoms may include fever and fatigue.

2. Causes of Muscle Pain Behind the Knee

2.1. Injuries

Sports injuries, traffic accidents, or workplace accidents can damage cartilage, joints, and ligaments, leading to pain behind the knee.

2.2. Baker’s Cyst

This occurs when a sac of fluid builds up at the back of the knee, causing pain and swelling. Small cysts may be painless, but as they grow, they put pressure on tendons and nerves. A Baker’s cyst can grow as large as a ping-pong ball.

2.3. Deep Vein Thrombosis (DVT)

DVT occurs when a blood clot forms in a deep vein in the leg. Overweight individuals, the elderly, smokers, and those with a sedentary lifestyle are at higher risk.

2.4. Bone and Joint Disorders

Although less common than general knee pain, muscle pain behind the knee can result from underlying joint conditions.

• Knee Arthritis: Symptoms include localized or cyclical pain, worsening discomfort, joint stiffness, and grinding sounds. Untreated arthritis may lead to complications such as osteoarthritis, ligament tears, and joint effusion.

• Tendonitis: Tears or ruptures in tendons or ligaments may cause pain, often behind the left knee.

• Knee Effusion (Fluid on the Knee): Excess fluid leaks into surrounding areas, causing swelling and pain behind the knee.

• Bursitis: Repeated strain on the bursa (fluid-filled sacs around the joint) leads to inflammation, redness, and swelling.

3. Treatment for Muscle Pain Behind the Knee

While not life-threatening, untreated muscle pain behind the knee can interfere with daily life and cause complications. Medical consultation is recommended to determine the appropriate treatment plan.

3.1. Western Medicine

Commonly prescribed medications include:

• NSAIDs: Ibuprofen, Aleve, corticosteroids to reduce pain and inflammation.

• COX-2 inhibitors: Etoricoxib, parecoxib, rofecoxib, valdecoxib, lumiracoxib.

⚠️ Long-term use may cause side effects affecting the liver, kidneys, and stomach. Medication should only be taken under a doctor’s guidance.

3.2. Traditional Remedies

Safer, natural alternatives are often chosen to avoid side effects:

• Gac Seed Remedy: Roast gac seeds, soak them in 2 liters of white wine for one month, and use the liquid to massage the painful area 2–3 times daily.

• Mugwort Remedy: Wash a handful of mugwort leaves, pound them with salt, dry-roast the mixture, and apply it to the painful knee area.

3.3. Hot and Cold Compresses

Applying heat or cold helps improve blood circulation, relax muscles, and reduce pain.

3.4. Acupuncture and Acupressure

These techniques help relieve pain immediately by improving energy flow and stimulating the body’s natural painkillers.

3.5. Surgery

Surgical intervention is recommended in severe cases where conservative treatments fail. The procedure removes or repairs internal knee damage.

✅ Muscle pain behind the knee may seem minor but can indicate underlying injuries or diseases. Early recognition and timely treatment are essential to prevent long-term complications.