Running is a fantastic means of keeping fit and has many health benefits for the heart, body and mind. However, each year up to 50% of runners suffer injury , the majority being overuse injuries of the knee. Contrary to this, Running is not Bad for your Knees. Pain can be an uncomfortable setback, but should be seen as motivation to address the issue early to enable us to return to enjoyable running.
A.K.A: Patellofemoral Pain Syndrome (PFPS), Anterior Knee Pain.
Pain around the knee, worsened by repeated use.
Not related to specific injury, rather a group of symptoms resulting from several possible causes.
No single Surgical or Rehabilitation Protocol is effective for everyone.
Treat the Cause, Not just the Symptoms.
PART 1: CHALLENGING CONVENTIONAL WISDOM
Degenerative Changes, Scans and Surgery:
Structural changes of the knee are Normal in Healthy, Pain-Free Individuals.
Scans can mislead runners by focusing on ‘faulty’ structures which needs fixing or removal.
This can reinforce Thought Viruses that ‘My Knee is Damaged’, and may actually increase pain levels.
Surgical removal of the ‘faulty’ structure might then be considered, but surgery is INEFFECTIVE for PFPS (Runner’s Knee). 
Where is my pain coming from?:
Identifying a structural source of Runner’s Knee based on pain alone is difficult.
Soft tissues of the knee are the Most Sensitive to pain and are well localised, whereas other structures are Poorly Sensitive and were difficult to localise. Patellar Cartilage shows no pain sensitivity.
Nerves of the knee may be the pain generating tissues, as they can increase in number  and size.
These adaptations may be the result of ongoing stress on the knee from poor Biomechanics.
Patella Maltracking + Position Faults:
Patellar positioning and tracking abnormalities are not a significant factor in Runner’s Knee.
These ‘Abnormalities’ are common and may even be Normal.
Exercises cannot specifically target the Inside Quad (VMO) over other Quads.
It is questionable whether VMO actually exists as a separate muscle to the Vastus Medialis (VM) 
VM activity is delayed in PFPS , most likely a result of Pain and Swelling , rather than the cause.
‘VMO-specific exercise’ do improve PFPS, most likely due to an increase in general Quads strength.
Summary of Conventional Wisdom
- Structural changes are common in healthy knees, and should not be regarded as a source of pain.
- Pain is a poor indicator of what/where the problem is.
- Surgery is ineffective for PFPS.
- Patella tracking/position ‘Abnormalities’ may actually be Normal.
- It’s not possible or necessary to isolate VMO in order to improve pain.
PART 2: WHAT DO I HAVE? WHAT HAVE I INJURED?
Most common ‘cause’ of Runner’s Knee seems to be a Dynamic Genu Valgum, or “Knock Knee” position, which increases Reaction Forces at the Knee, and may become painful when combined with repetitive loading (running).
BIOMECHANICS OF PFPS
Genu Valgum is mostly the result of altered Hip or Ankle Biomechanics which may be present before the onset of pain.
The foot needs to be able to adapt to the ground to dissipate Forces experienced. Sufficient mobility and strength are required for the leg to pass over the foot. If not, the foot may compensate by Over-Pronating leading to Genu Valgum. Flat Feet are commonly caused by poor Biomechanics at other joints.
Compensation for the above faults is common, by adopting a Toe Out Walk / Run. However the knee now travels straight over a turned out foot, resulting in Genu Valgum
Summary of PFPS Biomechanics
- Runner’s Knee is likely a result of Genu Valgum combined with Repetitive Use.
- Causes of Genu Valgum include poor Hip stability and Foot/Ankle Mobility.
PART 3: REHABILITATION
1. Dynamic Rest:
Keep active with pain free exercise – Run slower; Substitute with cycling or swimming.
Rest from painful activity allows for quicker reduction in pain.
Modify Daily Activities to reduce pain (bending, squatting, stairs, slopes)
2. Biomechanical Correction:
A Physiotherapist can identify the Biomechanical source of Your pain and develop a treatment plan for You.
3. Hip/Quad Strengthening
Strong Hip and Thigh muscles help absorb shock , better stabilise the Leg, and improve PFPS. 
The Step Up Exercise is very good for developing control and stability of the Hip and Knee
4. Tissue Flexibility
Reducing tension of the Hamstrings, Calf and Quads may reduce forces at the knee .
If this tightness is recurring, it may actually be a compensation for a weakness elsewhere.
It is very common for athletes to regularly stretch or foam roll, if they do not fix the underlying weakness.
5. Return to Running
Gradually return to running to ensure that a relapse does not occur. Take care on hills and hard surfaces.
Chris Johnson of Zeren PT provides a very helpful Return to Running Program.
R.I.C.E.:Rest, Ice, Compress, Elevate. A typical treatment for acute pains, however there is much debate about its effectiveness. For now, do what works for you.
Tape/Braces/Orthotics: Temporary devices to help you during your rehab. They do not correct the underlying issue but can reduce pain. Non-specific tapibg  and non-custom orthotics  are also effective options.
- Pain Free activity through modifying your training and daily activities.
- Correct underlying Biomechanical fault.
- Strengthen Hip and Quads muscles.
- Reduce muscle Tension to help relieve pain. Identify underlying cause of this tension.
- Return to Running Gradually.
- Use R.I.C.E., Tape, Braces or orthotics to assist in your Rehabilitation.
*Any questions, comments regarding the content of this article are highly welcome. You contact me on firstname.lastname@example.org.
**This article is for educational purposes only and should not never replace any diagnosis or treatment advice previous given to you by your therapist. Knee pain can occur from many factors, so it is important to visit a Physiotherapist to ensure you are accurately assessed and treated correctly.
***If any content of this article belongs to you and requires permission for use, I apologise and please contact me so I can replace it.