Why does the back of my knee hurt when I bend my leg?

Pain in the back of the knee (popliteal fossa) when bending the leg may be caused by overuse, muscle strain, nerve compression, ligament injury, arthritis, and other conditions. Targeted treatment should be based on the specific cause. If pain persists or worsens, it is advisable to seek medical attention promptly for diagnosis and treatment. Specific details are as follows:

1. Overuse

Prolonged or excessive use of the leg muscles can lead to muscle fatigue, causing soreness in the back of the knee when bending the leg. Resting in bed more often can help relieve muscle fatigue, and overexertion should be avoided.

2. Muscle Strain

When muscles are injured, an inflammatory response and local swelling may occur. Bending the leg places additional pressure on the injured muscle, triggering pain. Within the first 48 hours after injury, apply ice packs to the affected area at regular intervals to reduce swelling and pain.

3. Nerve Compression

When nerves are compressed, their normal function is impaired, leading to symptoms such as pain, numbness, and weakness in the areas they innervate. Under a doctor's guidance, medications such as Oryzanol tablets, Vitamin B12 tablets, and Mecobalamin tablets may be used to alleviate symptoms.

4. Ligament Injury

When ligaments are damaged, joint stability and range of motion are affected, resulting in pain. Bending the leg stretches and stresses the injured ligament further, potentially causing or worsening pain. Under medical advice, pain can be managed with medications such as Aspirin tablets, Ibuprofen tablets, or Indomethacin tablets.

5. Arthritis

Reduction of cartilage matrix in the joint makes it susceptible to damage from external mechanical stimuli, leading to aseptic inflammation and causing pain, stiffness, and swelling in the back of the knee when bending. Follow medical advice to take medications such as Celecoxib capsules, Etoricoxib tablets, or Diclofenac Sodium sustained-release tablets for treatment.

In daily life, applying heat to the painful area may help improve local blood circulation and relieve discomfort.