What causes patellofemoral pain syndrome?
We don’t yet fully understand all the causes of patellofemoral pain syndrome, but it’s most likely a combination of factors. Some factors that could lead to it are:
- weakness or imbalance in your thigh or buttock muscles
- tight hamstrings (the muscles at the backs of your thighs)
- short ligaments around your kneecap
- problems with weight bearing and alignment through your feet
An imbalance in the muscles surrounding your knee can put too much pressure on your kneecap and the cartilage in your joint. To understand why this happens, it helps to know a little about how your knee joint works.
The kneecap (patella) lies in a groove at the front of the lower end of the thigh bone (femur). It’s shaped to move up and down in the centre of its groove when you bend or straighten your knee. If the muscles or ligaments surrounding your knee cause your kneecap to move away from the centre of its groove, this can put too much pressure on the cartilage which lines the side of the groove and on a small area on the back of your kneecap. This pressure can lead to changes in a small area of cartilage where your kneecap meets your femur, which can lead to knee pain.