Patellofemoral Pain Syndrome (Runner's Knee): Causes, Symptoms, and How Physiotherapy Can Help

Reviewed by the Physiotherapy Team at Waterloo Sports Medicine Centre 

Pain around the front of the knee when running, squatting, climbing stairs, or sitting for long periods may be a sign of patellofemoral pain syndrome (PFPS), commonly known as runner's knee. This condition is one of the most common causes of knee pain in active individuals and can affect athletes, runners, and people who participate in recreational exercise.

What Is Patellofemoral Pain Syndrome? 

Patellofemoral pain syndrome refers to pain originating from the joint between the kneecap (patella) and the thigh bone (femur). The pain is typically felt around or behind the kneecap and often worsens during activities that place increased stress on the joint.

Common symptoms include: 

• Pain at the front of the knee 

• Discomfort during running, squatting, lunging, or stair climbing 

• Pain after prolonged sitting 

• Clicking or grinding sensations within the knee 

• Reduced ability to participate in sports or exercise 

  
  

What Causes Runner's Knee? 

Patellofemoral pain is usually caused by a combination of factors rather than a single injury. The condition often develops when the forces placed on the kneecap exceed the joint's ability to tolerate them. 

Common contributing factors include: 

• Sudden increases in running or training volume 

• Weakness of the hip and thigh muscles 

• Reduced lower-limb strength and endurance 

• Poor movement control during activities such as squatting or running 

• Overtraining without adequate recovery 

• Biomechanical factors affecting the lower extremity

Who Is at Risk? 

Several factors may increase the risk of developing patellofemoral pain syndrome: 

• Participation in running and jumping sports 

• Female sex 

• Previous knee injury 

• Muscle weakness around the hips and knees 

• Reduced physical conditioning 

• Rapid changes in training intensity or frequency

While runner's knee is common in runners, it can affect anyone who regularly performs activities involving repetitive knee bending. 

How Can Physiotherapy Help? 

Current clinical guidelines recommend exercise therapy as the cornerstone of treatment for patellofemoral pain

Following a thorough assessment, a physiotherapist may develop a treatment plan that includes: 

• Strengthening exercises for the quadriceps and hip muscles 

• Movement retraining for squatting, running, and other activities 

• Mobility and flexibility exercises 

• Activity modification and load management strategies 

• Education on training progression and injury prevention 

• Return-to-sport planning 

Research shows that exercise programs targeting both the hip and knee muscles can significantly improve pain and function in individuals with patellofemoral pain syndrome. 

How Long Does Recovery Take? 

Recovery timelines vary depending on symptom severity, duration of symptoms, and adherence to treatment. Early treatment often leads to better outcomes and may help prevent symptoms from becoming chronic. 

Many individuals begin noticing improvements within 6 to 12 weeks of a structured rehabilitation program. However, persistent cases may require several months of progressive strengthening and activity modification.

When Should You See a Physiotherapist? 

Consider seeking physiotherapy if: 

• Knee pain persists for more than a few weeks 

• Symptoms are limiting your ability to run, exercise, or participate in sports 

• Pain occurs during everyday activities such as stair climbing 

• Rest alone is not resolving your symptoms 

A physiotherapist can identify the underlying causes of your pain and help you return to activity with greater confidence and less discomfort. 

Looking for treatment for runner's knee in Waterloo or Kitchener? The physiotherapy team at Waterloo Sports Medicine Centre can assess your symptoms, develop a personalized rehabilitation plan, and help you safely return to running, sport, and everyday activities.