Anterior knee pain, patellofemoral pain, retropatella pain or any of the other common names for pain in the front of your knee are not diagnoses in themselves.
The most important step in finding a cure for the pain in the front if your knee then is to figure out what is actually causing the problem.
The following is a list of conditions that can cause pain in the front of the knee:
Excessive lateral pressure syndrome
This occurs when the patella sits or tracks towards the outside of the knee due to soft tissue tightness and weakness. As the name suggests, this causes excessive pressure on the outside part of the patella and femur beneath it. The jury is still out on the actual source of the pain in ELPS, but it is most likely a combination of stress on the soft tissues surrounding the patella and the effect of a decreased patella contact area on the outside part of the knee.
Chondromalacia is the softening and damage of articular cartilage. Chondromalacia is quite common and although it may be a source of pain, particularly in its later stages, I feel it is used as a diagnosis too often. Most knees (including my own) have some degree of chondromalacia, and studies have shown that knee cartilage does not cause any pain on its own.
Synovial plica syndrome
Synovial plicae are remnants of embryological structures that are found normally within the knee. The problem arises when these structures are irritated for any reason. This can be due to direct impact or repetitive pinching during activity. Initially plica can cause pain due to being inflamed. If this is not resolved, plica can become fibrotic resulting in pressure on the bone beneath and surrounding soft tissue structures.
Infrapatella Fat Pad Irritation
The infrapatella fat pad is a sensitive structure found beneath the patella. Like synovial plica syndrome, it can become irritated with direct trauma or due to repetitive excessive pressures during activity.
The patella and quadricep tendons can become inflamed due to overuse. If this is allowed to continue, the structure of the tendon can become disorganised, resulting in tendinosis.
Patella Motion Abnormalities
Pain can be caused if the patella does not move enough, moves too much or does not track properly. Not enough movement and the patellofemoral joint can be subjected to excessive pressure. Too much movement and the soft tissues surrounding the patella will be subjected to excessive pressure. And if the patella doesn’t track properly, both of these situations can occur.
If placed under repetitive load or stretch, nerves in and around the knee can become aggravated and sensitised, resulting in pain.
Quite simply, if you bang your knee on something hard, it’s going to hurt.
The hip and lower back can also refer pain to the front of the knee, so these areas should be considered when attempting to accurately diagnose the cause of the pain.
This may not be an exhaustive list, so if you feel I’ve missed something, please let me know by leaving a comment or posting on the Knee Pain Journal Facebook page.