Why do my knees ache the bones feel weak and saw?

See details: Knee pain in a 32 year can have several possible causes including arthritic inflammation, chondromalacia, tendinitis and bursitis among others. The only way to know the cause is to see a doctor and have the knees evaluated.

Many possibilities: Could be simply instability, but could also be arthritis, tendonitis or even fracture. Rheumatology or orthopedic evaluation required.