Whether you are playing for the local rugby club on the weekend, a seasoned runner, or a casual daily walker, anterior knee (knee cap pain) pain is a very common complaint among our patients. Anterior knee pain is also known as patellofemoral pain. The patellofemoral joint is complex, and its functionality relies on a balance of forces placed upon it by muscles and tendons.
Introducing the Patellofemoral Joint.
But what is the patellofemoral joint? The linchpin of the joint is the patella, also known as the knee cap. The function of the patella to increases the leverage that the patellofemoral tendon can exert. To help achieve this leverage, the patella relies on the balance of forces from surrounding muscles.
Namely, the Vastus Medialis Oblique (VMO), the inside quadriceps muscle, is immensely important in stabilising the patella and prevent lateral movement. Counteracting the VMO is the Vastus Lateralis (VL) of the quadriceps and the Illiotibial Band (ITB) which is influenced the Tensor Fascia Lata (TFL) muscle. So what causes an imbalance that can result in anterior knee pain (knee cap pain)?
Causes of Knee Cap Pain.
Among the most common causes of anterior knee pain is people either doing too much exercise (overusing their muscles) or they do too much exercise too soon. A sudden and large increase in the amount of exercise you do or simply doing too much can cause muscle fatigue with the stabilising muscles in both the buttock, butttock and ankle. This will increase the workload of the the hip, knee and ankle muscles during activity. This will result in these muscles becoming tighter which will start to create an imbalance of forces on the patella creating knee cap pain. Ongoing exercise will continue to exacerbate this imbalance. Adolescents that are going through a growth spurt and involved in exercise are more susceptible.
Other factors associated with patellofemoral pain are:
- A history of trauma including fractures or dislocations
- Being overweight
- Prolong sitting positions
- Arthritis, inflammatory conditions and cartilage or meniscus damage
- Poor biomechanics
- Due to genetics (how you are made up)
- Due to poor technique (running or walking) or specific sports specific biomechanics.
- Poor footwear
The patellofemoral tendon, connecting the patella to the tibial tuberosity, is often a source of anterior cap pain; either in the form of a tendinosis, an inflammatory change to a tendon from a micro trauma/tear, or a tendinosis that is degenerative changes to the collagen in the tendon from overuse. Understanding the difference is important when assessing patellofemoral pain as both have unique treatment methods.
What treatment is available?
Easing your anterior knee pain often needs a combination of effective manual techniques and progression of strengthening exercises. Hands-on techniques and the application of kinesiology tape are effective in stemming the pain and giving short-term relief. Though in the long-term, understanding the cause of pain and correcting this is far more important. Specific exercises are targeted at strengthening your pelvis (especially the gluteal muscles), and the VMO muscle of the knee (and all the muscles around the knee) are important and usually accompanied with a self-rolling program for the muscles. The muscles around the ankle (calf and the pretibial muscles) are also vital to address.
Biomechanically assessing the foot position and the alignment of the tibia/fibula is important and the impact on the patellofemoral tendon. Supporting the arch, first with tape then with an orthotic can improve patellofemoral function. If you are a runner looking at your running style can be a contributing factor, and running drills might need to be introduced.
While the knee can appear to more complex than it would seem, a thorough assessment is critical in determining the source of pain and implementing the most effective treatment strategy. Getting the right diagnosis is the first part of your treatment. Often this strategy is providing the patient with an effective self-management program tailored towards you knee cap pain. The right treatment will ease your pain and restore pain-free movement and function. Sustaining the self-help strategies is a long term project but well worth it.
Implementation of short, medium and long-term goals is important. Frustration can kick as flare-ups are quite common so the more you know about your knee cap pain, the better your outcome.
For more information on this injury, or to book an appointment to get on top of your knee pain, talk to your friendly Gold Coast Physio today on (07) 5574 4303!