Key Points
- There are 13 potential risk factors that are predictive of knee pain development.
- Risk factors are important to identify those at risk of experiencing knee pain.
- Being able to identify potential athletes helps develop prevention exercise programs early to avoid injuries.
Pain in the front of the knee. What can it be?
Pain in front of the knee can be due to a myriad of reasons but one of the more common cause of pain is a condition called Patellofemoral Pain (PFPS), or more commonly known as runner’s knee. It is a condition where one would experience pain in the front of the knee. PFPS is often described as pain in or around the kneecaps, and increases with functional activities such as squatting, kneeling, and stair climbing.
PFPS is reported to develop due to multiple factors rather than specific injuries. It typically occurs over time and when physical activity increases, causing nagging aches or occasional sharp pains that can limit daily activities.
Anatomically speaking, our knee joint functions as a hinge. The knee is inclusive of 3 key bone structures, the Femur (thigh bone), Patella (kneecap), and Tibia (shin bone), enclosed within a capsule. When we straighten and bend our knees, the patella glides smoothly over the Femur within the knee capsule to allow movement without pain.
The muscle structures in our legs and hips play a part in the proper hinging of our knee joints as well. Simply put, there are muscle groups on the front, back, and sides of our thigh that act out a delicate balance in the stability of our knees.
If these muscles are imbalanced, it will affect the angle at which our kneecap glides over our thigh bone, resulting in the unequal distribution of pressure when we bend or straighten our knees. This awry weight distribution contributes to the pain you may be feeling when you walk, climb the stairs, or squat.
Will I get pain in the front of the knee?
There are multiple factors that can cause PFPS. It is commonly diagnosed in patients less than 50 years old who complain of knee pain. The incidence rates reported in sports medicine are 25% to 43%, and studies see a higher incidence of women being diagnosed with PFPS compared to men.
A systematic review of the risk factors that can cause PFPS was done, summarising 13 potential risk factors. Who is at risk of getting PFPS?
Risk factors |
|
Demographics |
Females were at higher risk for development of PFPS |
Psychological parameters |
When looking at coping-behaviour mechanism, individuals who developed PFPS were observed to lack social support |
Physical fitness |
Individuals who participated less hours in sports per week eventually developed PFPS compared to those who had more hours. Participants with knee pain performed higher number of push-ups, but their vertical jumps were not as high as those without PFPS |
Joint angles |
Q-angle might be predictive of developing PFPS, but hip and knee angle variables concluded no difference between those with and without PFPS |
Posture |
Individuals with PFPS were observed to have a larger medial tibial intercondylar distance and higher navicular drop |
Patella |
Patella mobility did not show associations with PFPS development |
Vertical ground reaction force |
Individuals with PFPS had significantly lower vertical ground reaction force compared to those without PFPS |
Plantar pressure |
Contact of the foot with the ground was different in individuals with and without PFPSS |
Electromyographic Onset Timing of Vastus Medialis Obliquus (VMO) and Vastus Lateralis (VL) |
Thigh muscle activation imbalance was seen in patients with PFPS compared to those without |
Flexibility |
Lesser flexibility in the calves and thigh muscles was significantly associated with future development of PFPS |
General joint laxity |
Greater range of motion in knee straightening mobility is associated with future occurrence of PFPS |
Strength |
Reduced knee straightening strength is a significant risk factor in developing PFPS |
Peak torques |
In patients who developed PFPS, knee extension concentric peak torque was significantly lower than participants without PFPS |
Why is it important to know who is at risk
PFPS is not a condition that will resolve itself over time. In fact, if left untreated it can affect daily living, and prolongs recovery time when treatment is sought out. Considering how common PFPS develops in young individuals and athletes, it highlights the importance of finding out who is at risk. So how can we identify those at risk of developing PFPS, and why is it so important?
Preventing pain in the front of your knee
Prevention is key. Rather than treating PFPS after it has developed, we can focus on preventing it before it does. This is done so by knowing what risk factors lead to the development of PFPS, which then helps us to identify those with a possibility of getting it. When we can identify athletes at risk, we can develop prevention exercise programs for them earlier in order to avoid knee injuries and pain.
What can you do to minimise the risk of experiencing any front of knee pain?
The first step to minimising any risk of experiencing knee pain is to know what factors are associated with it. Then, the focus is on developing a prevention exercise program. The exercise program should include strengthening exercises for the hips and knees. Particularly for females, exercises that focus on quadriceps muscle strengthening may be effective in keeping the knee pain-free. In addition, take into consideration your current physical activities and keep note of areas in the lower extremity that feel weak or tight as they may need to be addressed as well, to ensure the best outcomes.
Unsure of how you can address the pain in the front of your knee? Contact us to schedule an appointment with our Physiotherapist who will help address your pains.
Ref:
Anterior Knee Pain: As an Athlete, Am I at Risk?. (2012), 42(2), 95-95. https://doi.org/10.2519/jospt.2012.0502
Lankhorst, N., Bierma-Zeinstra, S., & van Middelkoop, M. (2012). Risk Factors for Patellofemoral Pain Syndrome: A Systematic Review. Journal Of Orthopaedic &Amp; Sports Physical Therapy, 42(2), 81-A12. https://doi.org/10.2519/jospt.2012.3803