Patello-Femoral, or Knee-cap Pain is one of the most common knee complaints – suffered by both sportspeople and the everyday person alike.
Knee-cap pain is experienced behind the knee-cap when there is an excessive build-up of force pushing the ridge on the back of the Knee-Cap (Patella) into the groove on the thigh bone (Femur).
This can be due to poor alignment of the knee-cap and is made worse by any degenerative change in the surface of either of these bones.
Knee-cap pain is sometimes called “movie-goers knee”, as even the subtle force of keeping the knee bent for a long time can irritate the knee of people with Patello-Femoral pain.
What causes Patello-Femoral pain?
As the knee bends, the Knee-Cap glides up and down in a groove on the end of the thigh bone called the trochlea. The more the knee bends, the more the Knee-Cap is pulled into the trochlea and the pressure between the two bones increases. There are two surfaces on the back of the Knee-Cap, and if the alignment of the Knee-Cap is altered, the Knee-Cap starts to mis-track and leads to a shift in how this pressure is shared between the two surfaces. If this change in pressure is present for long enough and is repeatedly irritated, Knee-Cap pain ensues. This can eventually lead to degeneration of the surface of either the back of the Patella or the Trochlea groove.
The most common causes of kneecap mal-alignment are an abnormal muscle imbalance of the quadriceps and poor control of the alignment of the lower limbs when walking or running.
Aching Knee-Caps (Patello-Femoral pain) will affect 25% of the population at some time in their lives, but it is more common in athletes. The sports where Patello-Femoral pain syndrome is typically seen are those when running, jumping and landing or the squatting position is required, such as running, tennis, netball, football, volleyball, basketball, skiing and other jumping sports.
Why is there a muscle imbalance in my Quadriceps?
The quadriceps are the muscles at the front of your thigh.
They connect directly into the Knee-Cap and if there is an imbalance between the muscle that pulls the Knee-Cap up and outwards (vastus lateralis) and the muscle that pulls up and inwards (vastus medialis) then the Knee-Cap will track slightly outwards (laterally) in the trochlea groove.
Longstanding tightness of structures on the lateral side of your knee (such as the iliotibial band) will encourage your Knee-Cap to drift sideways over time. Especially, if your vastus medialis is also weak.
What does Knee-Cap pain feel like?
People with Knee-Cap pain mostly complain of pain that develops gradually over time more than suffering a traumatic event. They will complain of pain behind the Knee-Cap with activities that increases pressure on the knee-cap such as stairs, squatting, kneeling, hopping or running.
As your Knee-Cap pain progresses your knee will become painful while walking and then ultimately even at rest. You can also experience Knee-Cap pain when you are in sustained position with your knee bent (“movie-goers knee”).
How do you treat Patello-Femoral (Knee-cap) pain?
Researchers have confirmed that physiotherapy treatment is a very effective short and long-term solution for people with Knee-Cap pain. About 90% of patients will be pain-free within six weeks of commencing a physiotherapy guided rehabilitation program for Knee-Cap pain.
Your Leading Edge physiotherapist will guide you through your rehab from Patello-Femoral pain. Strategies that may be employed could include:
- Reduce the amount of pain and inflammation present in the joint by using ice
- Protecting the kneecap from further irritation by using specialised taping techniques to restore the normal tracking of the Knee-Cap in the trochlea groove
- Restore normal movement in the muscles and ligaments that connect to the kneecap by using massage and mobilisation techniques of the Patella.
- Restore normal function to the quadriceps and hip muscles to restore the tracking of the patella and alignment of the lower limb during activities such as walking and running.
I've hurt my Knee-Cap, what should I do right now?As soon as possible, and for 72 hours after injury, use the RICE method:
- Rest - Take it easy and only move within your limit of pain.
- Ice - As soon as possible, and for 20 minutes every two hours, apply ice or a frozen gel pack wrapped in a damp towel. This helps to control bleeding and pain and reduces secondary tissue damage.
- Compression - Firmly bandage the injury. This helps to control swelling.
- Elevation - As much as possible, elevate your injury higher than the level of your heart to reduce swelling.