Dr Alex Eade (Osteopath)
I have seen a few patients come in recently with anterior (front) knee pain, with a history that is not quite clear. They do not have a specific moment or have a mechanism of injury. When this kind of case is presented, further questioning needs to take place to get an insight of the recent events that have taken place. Checking if they have started a new training program or have increased the volume of training recently.
Patellofemoral tracking syndrome
Patellofemoral tracking syndrome is an umbrella term used to diagnose patella (kneecap) pain. That pain is caused by mechanical dysfunction of the patella not sliding evenly up and down the knee when you flex and extend. This is normally attributed by a variety of altered muscle control or movement. The patella acts like a pulley with the quadriceps and when the knee is flexing the compression force of the patella increases.
At 60-90 degrees of knee flexion, is the point of maximum compression force and the most contact the patella has on the femur. When the quadriceps contract it pulls the patella laterally towards the outside of the knee. This lateral pull can be increased by other factors such as the arch of the foot collapsing or poor glute control at the hip and may lead to the knee dropping inwards.
What specific structure is causing the pain?
An article by Dye, Vaupel & Dye et al 1998, to determine which knee structures were most sensitive to produce pain. This involved a surgeon having his knee scoped without anesthesia to determine the most painful structures. What he ranked worst was the infrapatellar fat pad and what was least was the cartilage of the knee cap.
Fat Pad irritation is the overuse injury that commonly gets overlooked.
Though keep in mind other differential diagnosis and to seek your Osteopath for medical advice.
Management
Can be caused by compression for example from kneeling down too long or/and from mechanical overuse. Involving similar mechanisms explained earlier, the overuse can be caused by running or anything else that requires high volume work from the knee. Modification and reduction of the volume stress is necessary to aid in recovery of the fat pad. Among other things that can be helpful like manual therapy and exercise rehabilitation.
Reference:
Dye, S., Vaupel, G., & Dye, C. (1998). Conscious Neurosensory Mapping of the Internal Structures of the Human Knee Without Intraarticular Anesthesia. The American Journal Of Sports Medicine, 26(6), 773-777. doi: 10.1177/03635465980260060601
Patellofemoral Joint. (2020). Retrieved 2 June 2020, from https://physio-pedia.com/Patellofemoral_Joint#sts=Factors%20affecting%20lateral%20tracking%20of%20the%20patella