This is likely to be;
1) Osteoarthritis (degenerative arthritis)
2) Injuries to the soft tissues (ligaments, muscles, tendon).
You need an x-ray and an MRI for the assessment.
Meanwhile following would help;
1) Knee care in the activities of daily living. Few simple self-care measures can be remarkably effective in ending pain cycle.
a) Avoid prolonged standing or walking or sitting with the joint in a single position.
b) whenever you sit, keep the knee stretched and fold them intermittently.
c) Squatting, sitting cross-legged should not be done.
d) Avoid climbing stairs.
e) Avoid sitting legs unsupported or hanging.
f) Reduce weight if overweight/obese.
2) Rest: Taking a break from your normal activities reduces repetitive strain on your knee, gives the time to heal and helps prevent further damage.
3) Anti-inflammatory medications
4) Physical therapy; the goal of physical therapy is to strengthen the muscles around your knee and help you regain knee stability. An ideal is supervised physical therapy. Stretching exercises are also part of the physical therapy regime.
5) Orthotics and bracing.
7) Light massage
8) Deep electrotherapy
9) Warm Compresses
10) Local analgesic spray.
Please feel free for your follow up questions.
I would be happy to assist you further if you need any more information.
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