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"Why did my knee give out?"

ZocdocAnswersWhy did my knee give out?


My knee just gave out yesterday. No other way to explain it. I was walking and it went weak and just gave out and I went down to one knee. Why did this happen? Should I get my knee checked out to make sure there is some kind of major problem that I don't know about?


There are several different causes for the sensation of the 'knee giving out.' If this just occurs once, and if there is no residual pain or swelling or other concerning symptoms, then it may just be that you accidentally stumbled or tripped, causes you to go down to one knee. On the other hand if this has occurred more than once, or if it reoccurs, then you will definitely need to be evaluated by your primary care doctor for an underlying cause. Some of the underlying causes that can cause this problem would include arthritis of the knee, damaged to the ligaments or other connective tissue in the knee, or problems with movement of the knee cap (patella) over the underlying leg bones. Additionally, it would be a good idea to see your doctor to make sure that you didn't injure your knee when you fell on it yesterday. They can examine the knee for any signs of tenderness, instability, or pain and help you decide whether you need further immediate evaluation (such as an x-ray) or treatment (such as a brace, crutches, or anti inflammatory medications). Get in to see your primary care doctor as soon as you can!

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