What could cause knee pain with numbness in the lower leg?

Knee pain with numbness in the lower leg is often caused by nerve compression or injury. The sciatic nerve (running from the lower back down the leg) and the peroneal nerve (wrapping around the outer knee) are the most common culprits. When these nerves are pinched, irritated, or damaged, they can trigger pain in the knee alongside numbness, tingling, or weakness in the lower leg and foot.

Common causes include:

• Herniated disc in the lower back pressing on the sciatic nerve
• Peroneal nerve injury from crossing legs, prolonged kneeling, or trauma
• Spinal stenosis or degenerative changes narrowing nerve pathways
• Diabetic neuropathy or other systemic nerve conditions

Because knee pain with numbness can point to several very different underlying conditions—some minor, some serious—it's important to identify the likely cause before deciding on next steps. A free, instant, online symptom check can help you quickly narrow down possible causes based on your specific symptoms, guide you on whether to see a doctor, and suggest which specialist may be most helpful. It takes only a few minutes and could save you time, worry, and unnecessary appointments.

Reviewed for medical accuracy: 07/14/2026