Patello-femoral knee pain
This is a subject which interests me quite a bit as it appears to be a diagnosis that get used a little too often. The reason for this is because it is not a very specific diagnosis, it basically means that there is pain behind and around the patella, which doesn’t explain much.
The reason that patellofemoral knee pain can come on is usually due to poor patella tracking between the femoral condyles. A line drawn from the ASIS (the bony bit on the front of your pelvis on your side) to the inferior pole of the patella (the lowest point of your knee cap) intersected with a line straight up from the floor forms and angle called the Q angle. See picture below
In Males the Q angle should be 13 degrees and in women it should be 18 degrees (as women have a larger pelvis) when the knee is straight. too much deviation away from these normal angles can cause an increase in friction at the condyles (parts of the knee at the end of the femur upon which the knee cap slides) during movement and may lead to irritation or even early wearing of the cartilage in this region (known as chondromalacia patella), the pain as a result of one of these problems is usually known as patellofemoral knee pain. Often however, another problem which is poorly diagnosed can get chucked in under the diagnosis of patellofemoral knee pain as it is such a general diagnosis.