These articles have quotations from film adaptations of J.R.R. Tolkien's novel The Lord of the Rings and related works: 1  The Lord of the Rings.  J.R.R. Tolkien's The Lord of the Rings (1978)
This causes a twisting on the tibia and changes its relationship to your kneecap. This can cause tracking problems as well. If your quadriceps or hamstring muscles are too tight, they also will affect the mechanics of the knee and lead to compensation patterns that cause pain.
There are also muscular causes. Tight hamstring and calf muscles put pressure on the knee, and weak quadriceps muscles can cause the patella to track out of alignment. Just the repetitive force of a normal running stride alone can be enough to provoke an attack of runner's knee.