Call for emergency medical help. If you suspect you're having a heart attack, don't hesitate. Immediately call 911 or your local emergency number. If you don't have access to emergency medical services, have someone drive you to the nearest hospital.
The most common causes of knee weakness are osteoarthritis, sprain or strain, and chronic knee pain. Other possible causes, such as injury to the knee, are more rare. Osteoarthritis 22. Sprain or strain 17. Chronic knee pain 15. Knee ligament or meniscus tear 8. Fracture of the leg 4. Bursitis 2.
Specifically, a link of sciatica as a cause of knee pain is very possible. Sciatica is condition of the body that is generally characterized by pain in one or both of the legs. This is because the sciatica nerve extends down both legs. Additionally, the pain may range any where from being moderate to severe pain.