What causes soreness and pain in the back of the knee?

Acidic pain in the back of the knee is generally related to physiological causes, such as excessive exercise, but may also result from pathological conditions including meniscus injury and lumbar disc herniation. Prompt medical treatment is recommended once symptoms occur. Specific analyses are as follows:

I. Physiological Causes

Sudden intense physical activity without proper warm-up can lead to excessive lactic acid production in the legs, which accumulates in the popliteal area and causes pain. It is recommended to rest in bed, avoid strenuous exercise, and allow gradual recovery through appropriate self-care.

II. Pathological Causes

1. Meniscus Injury

This condition is often caused by long-term weight-bearing or sudden twisting of the joint, leading to damage of the collateral ligaments and cartilage surfaces. This results in localized knee pain and discomfort, with severe cases possibly accompanied by joint clicking. Patients should follow medical advice for medication, such as diclofenac sodium sustained-release tablets, meloxicam tablets, or ibuprofen sustained-release capsules, all of which can help alleviate pain.

2. Lumbar Disc Herniation

The protruding intervertebral disc compresses nerve roots, affecting lower limb health and causing low back pain and leg pain. In severe cases, normal walking may become impossible. After diagnosis, patients may take medications as directed by a physician, such as indomethacin enteric-coated tablets, sulfasalazine tablets, or nimesulide sustained-release capsules, to achieve pain relief.

In addition, similar symptoms may also be associated with conditions such as popliteal cyst, hypertrophic osteoarthritis, or avascular necrosis of the femoral head. It is advisable to seek timely medical evaluation at a hospital and select appropriate treatment options under professional medical guidance.