I am a competitive runner. During my training for a marathon, I increased my mileage. Shortly after that, I twisted my ankle while running. My ankle doesn’t hurt, but my knee does. There’s a painful tenderness along the outside of the knee, just below the joint. Can an ankle sprain cause pain at the knee?
Yes. Anytime there’s an injury, problems can occur in the joint above or below that injury. It’s possible that you hurt your knee and your ankle at the same time. If the ankle injury is more painful or obvious, the other trauma may be missed for some time.
The force of the injury through the ankle can also put a twisting load on the joint just below the knee. This is the tibiofibular joint, the place where the two bones of the lower leg (tibia and fibula) meet.
Before continuing training, it would be a good idea to have this evaluated. There could be a bone fracture, torn ligament, or stretched nerve causing these symptoms. Treatment now may help prevent a worse injury later.
Jon K. Sekiya, MD, and John E. Kuhn, MD. Instability of the Proximal Tibiofibular Joint. In Journal of the American Academy of Orthopaedic Surgeons. March/April 2003. Vol. 11. No. 2. Pp. 120-128.