Knee Osteoarthritis: Symptoms, Causes, and How Physiotherapy Can Help

Reviewed by the Physiotherapy Team at Waterloo Sports Medicine Centre  

What Is Knee Osteoarthritis? 

Knee osteoarthritis (OA) is the most common form of arthritis affecting the knee joint. It is a condition where the tissues inside the knee gradually change over time, including the breakdown of cartilage that helps the joint move smoothly. These changes can lead to pain, stiffness, swelling, and reduced function. 

Although knee osteoarthritis is often associated with aging, it is not simply a result of “wear and tear.” OA involves changes to multiple structures within the joint, including cartilage, bone, ligaments, muscles, and the surrounding tissues. 

Common symptoms of knee osteoarthritis include: 

• Knee pain that worsens with activities such as walking, stairs, squatting, or prolonged standing  

• Stiffness, especially after sitting or in the morning  

• Swelling around the knee joint  

• Reduced range of motion  

• Clicking, grinding, or a feeling of the knee “catching”  

• Difficulty performing daily activities or recreational sports  

What Causes Knee Osteoarthritis? 

Over time, a combination of factors affect knee joint health: 

• Age: The likelihood of developing OA increases as tissues experience changes over time.  

• Previous knee injuries: Injuries such as ligament tears, meniscus injuries, or fractures may increase the risk of developing arthritis later in life.  

• Repetitive stress: Jobs, sports, or activities involving frequent kneeling, squatting, or heavy loading may contribute to joint stress.  

• Muscle weakness: Reduced strength, particularly in the quadriceps and hip muscles, may affect how forces are distributed through the knee.  

• Body weight: Increased body weight can increase the load placed on the knee joint during daily activities.  

  
  

Having knee osteoarthritis does not mean that movement should be avoided. In fact, appropriate exercise is one of the most effective ways to manage symptoms and maintain knee function. 

How Can Physiotherapy Help Knee Osteoarthritis? 

Physiotherapy is a key component of conservative knee osteoarthritis management. A physiotherapist can assess your knee strength, mobility, movement patterns, and daily activities to develop an individualized treatment plan. 

Exercise Therapy 

Exercise is one of the most strongly supported treatments for knee osteoarthritis. Research shows that exercise programs can help improve pain, physical function, and quality of life for individuals with knee OA.

• Strengthening exercises: Targeting muscles such as the quadriceps, hamstrings, and hip muscles to improve knee stability and reduce joint stress.  

• Mobility exercises: Improving knee flexibility and reducing stiffness.  

• Balance and functional training: Helping improve walking, stair climbing, and movement confidence.  

• Low-impact aerobic exercise: Activities such as cycling, swimming, or walking to improve overall fitness while supporting joint health.  

  
  

Progressive resistance training has also been shown to improve pain and physical function in individuals with knee osteoarthritis, with benefits seen in programs lasting several months.

Manual Therapy and Education 

Depending on your symptoms, physiotherapists may use hands-on techniques such as joint mobilizations or soft tissue techniques to help improve movement and comfort. Physiotherapy also focuses on education, including: 

• Understanding your diagnosis  

• Learning safe ways to stay active  

• Modifying activities when needed  

• Developing strategies to manage flare-ups  

  
  

How Long Does Knee Osteoarthritis Take to Improve? 

Knee osteoarthritis is a long-term condition, meaning symptoms may fluctuate over time. While physiotherapy cannot reverse cartilage changes that have already occurred, it can significantly improve pain, mobility, strength, and quality of life. 

Many patients notice improvements within several weeks of starting a structured exercise program, although meaningful changes often require consistent effort over several months. Research suggests resistance exercise programs lasting approximately 3–6 months can improve pain and function in people with knee OA.

When Should You See a Physiotherapist? 

You do not need to wait until knee pain becomes severe before seeking help. A physiotherapist can help if you are experiencing: 

• Persistent knee pain during daily activities  

• Increasing stiffness or difficulty bending the knee  

• Reduced ability to exercise or participate in sports  

• Concerns about knee arthritis progression  

• Difficulty managing symptoms on your own  

Looking for Knee Osteoarthritis Treatment in Kitchener-Waterloo? 

Waterloo Sports Medicine Centre provides evidence-based physiotherapy services to help patients manage knee pain and return to the activities they enjoy!