Knee pain ~ Joint supplement works?

Does it really work?

Get knee pain ....

   I have been running to keep my fitness regular basis.  However, I sometimes get knee pain last a few years.  I guess it is because of age and a surgery about 20 years ago.   I met an avalanche in a mountain and air lifted in December 1999.  Due to the accident my left knee was broken and got a surgery with artificial born.   It's been about 20 years, I guess it might be one of the reason of the pain.

   I also saw a doctor a several times, however, no obvious reason was found in the past.   On the other hand, I had some injury especially shin-sprint and stress fracture on my left leg and I have to stop training often.   My muscle strength might be getting weaker.  I guess they might be a part of reasons I am getting the knee pain last several years.

The pain is usually gone when I take a rest.....

   Most of time till last year, the pain was going away as long as I stop running for a few days and I did not see much problem.  However, the pain happened this January, the pain was worse and it tool longer to be back to normal.   So I started worry about the pain.

The Pain

   The pain is around lower part of knee.  Based on my research, the pain might be a lack of flexibility.  So that I spent more time for stretching before / after training.  However, it did not help so much.
    The knee is sore and I felt really sharp pain.   When I took pain killer, it was improved.  However it is not a treatment to avoid the pain and I had to stop training often.   On the other hand, some light training such as station bike / Elliptical, it was usually getting better.  I just carefully watch what it goes.

Trying a joint supplement.....

   Last 2 weeks, I try a joint supplement.   I recognize that many articles indicates that the effectiveness is questionable.   The primary ingredients are glucosamine and chondroitin.  There is no clear scientific prove, especially through mouth.  On the other hand, advertisement  from many distributors / vendor of those supplement shows many good things about the product.

   As I recognize those facts, I have been trying a supplement since there is almost no side effect.  It's been for 2 weeks, it seems that the pain is getting improved.   I am not really sure if it is due to the suppliment or placebo....　The fact is the pain is obviously getting better with almost regular running on treadmill instead of running on paved roads.

　Anyway, my left knee is getting something not right.  I will see a doctor soon anyway.  However, I want to get some feedback from readers who had some experience or opinion.
   What do you think??