Pain in the knee doesn’t always have its roots in the knee itself. Compression of the sciatic nerve, which begins in the lower back, can be responsible for the discomfort.
With a diameter the size of a finger, the sciatic nerve is the largest nerve in the human body. It begins at the 4th and 5th lumbar vertebra in the lower back and extends down through the leg towards the feet.
When the sciatic nerve becomes compressed, it can cause pain to radiate from the lower back through the buttocks and down the leg to below the knee, sometimes even as far as the big toe. The pain can be dull, sharp, or burning, and usually intensifies when leaning forward, straining, or coughing. Sciatic knee pain can be felt in the front of the knee or down the back of the leg.
All sciatica, including pain in the knee, is caused due to compression of the sciatic nerve. This could be due to a slipped disc or fracture. Even something as innocent as sitting on a thick wallet can cause the condition to develop.
Even though the pain may be felt in the knee, the source of compression could be anywhere along the nerve. Once the more serious causes are ruled out, most sciatica is treated with physical therapy and stretching.
It’s important to have a doctor properly diagnose the condition. The sciatica knee pain may actually be a herniated disc, arthritis, bursitis, or even irritable bowel syndrome.