What to do if your Knee Hurts when Bending


More than a quarter of adults suffer from regular bouts of knee pain. It’s really no surprise as our knees handle a tremendous amount stress day-to-day.1-2 Scientists have found that for every pound of bodyweight, our knees are subjected to up to seven pounds of pressure when they are bent or in weight-bearing.3 If you’re here, it is because you’ve noticed that your knee hurts when bending it, is painful walking down stairs and feels uncomfortable while squatting. The fix for this really depends on the diagnosis. Below are some common causes of knee pain.  

How did you hurt your knee?

Traumatic injuries are noticeable right away and worsen dramatically the next day as pain and inflammation set in. traumatic injuries typically occur playing sports, during slips, falls, and other work-related accidents. The trauma is caused by the injury exceeding the tolerance of knee structures leading to breaks, ruptures or tears.

Knee ligaments, bones, and menisci are the most commonly damaged structures in the knee joint. Injuries to bone and connective tissue result in long term pain and will impede normal knee function for some time after the initial injury. Less serious traumatic injuries may result in only painful, superficial contusions (bruises) which heal relatively quickly. If you believe you have incurred serious knee trauma you should visit a doctor as soon as possible. If bone or connective tissue within your joint is damaged a surgical assessment could be required.

Overuse injuries typically cause knee pain that comes and goes and varies in intensity. Sometimes our favorite activities subject our knees to stressful movement patterns repetitively. Think jumping, squatting, kneeling, running, lunging type movements. Moving in this way over and over again can irritate knee structures such as bursae, tendons, and articular cartilage.

Degenerative Joint Disease (arthritis) is the number one cause of long term disability relating to knee pain. Pain often comes on slowly and over time those affected by arthritis will experience constant pain while performing weight-bearing activities.

Knee arthritis comes in a variety of forms, osteoarthritis being by far the most common. Osteoarthritis develops over a long period of time and your knee may not hurt during the early stages of the disease. Once your cartilage has worn away, bone on bone pressure develops within the joint. This causes pain as pressure is placed on the knee.

As the disease progresses, bone spurs begin to develop resulting in joint stiffness and mobility losses. Osteoarthritis is most common in people over 50 with those that are younger being much less likely to experience the disease. While age is a major influencer of arthritis progression it is only one of many predisposing risk factors to consider.

Where does your knee hurt?

  • Knee pain on the front of the joint could be patellar arthritis or patellar tendonitis. These conditions tend to hurt when bending the knee, kneeling and/or squatting. Typically the deeper the knee bend the worse it will hurt.
  • The discomfort localized to the medial or inside of the knee could indicate tibiofemoral arthritis or meniscal irritation.  
  • Nagging pain or pressure that is localized to the back of the knee could be a sign that you’ve damaged your meniscus. It is also possible that you irritated the popliteal muscle and surrounding area.

My knee hurts when bending – What Now?

1 – Managing Knee Pain

Knee pain is usually the result of inflammation – a natural response from your immune system to damaged joint tissue. Pain and inflammation are completely normal and necessary for proper joint healing. Despite being “natural” joint inflammation can negatively influence your quality of life. Your knee may hurt so much that it makes day to day tasks difficult. In such cases, reducing inflammation with NSAIDs, the R.I.C.E. method and exercise are often used to manage pain in the short-term.

2 – Professional Knee Exam

Getting your knee assessed by a healthcare professional is crucial. This is even more important if you have suffered a traumatic knee injury. A definitive diagnosis will give you peace of mind and help expedite the healing process.

Two doctors discussing patient's knee pain as they bend it and test it

3 – Getting Rid of your Knee Pain

If you are lucky, your knee pain may get better on its own with rest. However, more than likely you will need to engage in rehab exercises to overcome the injury. Physiotherapists specialize in providing specific exercises and treatment regimes that increase the strength, stability, and mobility of your joint.  

Additional Resources

Frequently Asked Questions

Why does my knee hurt when I bend it?

There are a number of possible injuries that could be causing this type of knee pain. A key thing to consider is whether the pain developed suddenly or came on slowly. Have you had a previous injury to the knee? This increases the risk of re-injury dramatically. Lastly, the location of the pain is a big clue as to the underlying cause of your pain.

How do I fix my knee pain?

The fix for your knee pain really depends on the underlying cause. For the majority of knee injuries, exercise and balance training are crucial in the recovery phase. Muscle weakness, poor movement patterns, and poor balance are often linked to those in pain. Working with a healthcare professional such as a physiotherapist, or a personal trainer can help you get started with exercises that are right for you.

What are some quick fixes for knee pain?

Ice, NSAIDs, and compression wraps can all reduce inflammation in the knee joint. It is important to remember that these treatments tackle the symptoms, not the underlying cause. Understanding why your knee hurts is crucial for long term relief.

How long will my knee pain last?

This really depends on your injury. If nothing is structurally damaged in your knee it could resolve itself in 1-2 weeks with rest. If you have knee arthritis, you may have to manage your knee pain for the rest of your life. Traumatic sports injuries requiring surgery may take up to a year to fully resolve.


  1. Nguyen, U. S. D., Zhang, Y., Zhu, Y., Niu, J., Zhang, B., & Felson, D. T. (2011). Increasing prevalence of knee pain and symptomatic knee osteoarthritis: survey and cohort data. Annals of internal medicine, 155(11), 725-732.
  2. Bunt, C. W., Jonas, C. E., & Chang, J. G. (2018). Knee Pain in Adults and Adolescents: The Initial Evaluation. American family physician, 98(9).
  3. Reilly, D. T., & Martens, M. (1972). Experimental analysis of the quadriceps muscle force and patello-femoral joint reaction force for various activities. Acta Orthopaedica Scandinavica, 43(2), 126-137.

By Simon Watts

Simon Watts is a former strength and conditioning coach with an extensive background in orthopedics and athletic therapy. He has a wealth of experience with the rehabilitation of common knee injuries such as osteoarthritis, meniscus tears, ligament injuries, and tendonitis. Simon studied Kinesiology at Dalhousie University, and as a track and field student-athlete was a national champion in the high jump and triple jump. He continues to be actively involved in the track and field community in Nova Scotia as a coach.

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