My knee hurts when it bends while I'm walking - what could be wrong?

Answer by  Huntress (1935)

There are several things that could be wrong: arthritis, fluid in the joint, debris or bone spur (you will hear some grinding or popping). All of these will cause pain when you bend your knee. I'm sure there are other probable causes but these are the ones I'm familiar with since I eventually had to have knee surgery.

Answer by  diva25 (4016)

It is possible that you sprained it, and that would not be too bad. There are lots of other things that you could have done and the best thing to do in this case is to go see a doctor about it.

Answer by  ferfer72 (2623)

You could have water on the knee. You could have pulled a muscle or tendon. You could have arthritis. Go see a doctor.