Hello, this situation may be traumatic synovitis, meniscus injury and so on. You can do a magnetic resonance imaging (MRI) to see. Treatment is mainly acupuncture, physiotherapy, external ointment, injection lubricants, oral anti-inflammatory analgesic, soothing medicine treatment, serious cases need surgical treatment. Pay attention to avoid the affected limb fatigue, strenuous exercise do not walk too much, avoid cold and so on
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