Knee joint: 1, pain induced by knee flexion or squatting: internal and external meniscal tear injury, lateral disc meniscus injury, anterior and posterior cruciate ligament cyst, medial synovial crease syndrome, patellar tilt extrusion, patellar subluxation, bone marrow edema, etc.; 2, knee joint extension and flexion with rattling: lateral disc meniscus, knee synovial hyperplasia, patellar instability, etc.; 3, knee joint instability caused by ligament injury belonging to the knee joint Stability: including anterior and posterior cruciate ligament rupture, medial collateral ligament injury, posterior lateral horn injury, knee dislocation combined with multiple ligament injury; 4, repeated swelling and fluid accumulation in the knee joint caused by a variety of reasons, resulting in synovitis of the knee joint: pigmented villous nodular synovitis, gouty synovitis, rheumatoid synovitis, infectious synovitis, synovitis complicated by ankylosing spondylitis, etc. 5, congenital or trauma-induced patellar dislocation: patellar cartilage injury, patellar medial support band injury; 6, joint interlocking (stuck) resulting in temporary restriction of movement: meniscus wider tear, joint free body (joint rat), synovial chondromatosis, etc. 7. Cartilage damage due to trauma or internal causes: exfoliative osteohoseitis, traumatic cartilage defect. Shoulder joint: 1. Shoulder joint instability: shoulder joint dislocation or repeated dislocation due to trauma or minor external force. 2. Diseases caused by shoulder joint pain: Calcified tendonitis of supraspinatus, subdeltoid bursitis, biceps longus tendonitis, acromioclavicular arthritis, osteoarthritis of the shoulder joint, etc. 3. Restriction of shoulder joint movement, pain from elevation or internal retraction: acromioclavicular dislocation, acromioclavicular impingement, frozen shoulder, etc. 4. Weakness of shoulder joint elevation: rotator cuff injury. 5. Local sensory loss and muscle atrophy around the shoulder joint: suprascapular nerve entrapment syndrome. The torn knee meniscus was repaired with minimally invasive sutures and microscopic views. The patient with synovial chondrosarcoma of the knee had a large amount of free bodies in the joint cavity microscopically. Minimally invasive debridement is recommended for a pigmented villous nodular (solitary) synovitis of the knee. Normal anterior cruciate ligament, injured ruptured anterior cruciate ligament and surgically reestablished anterior cruciate ligament