Arthroscopic approach to the meniscus: 2-3 small incisions of about 5mm in length, MRI clearly shows the medial meniscus (the black triangle is the image of the meniscus) posterior horn 3 degree injury signal (linear and passes to the edge of the meniscus, white high signal, indicating that the fluid enters inside the meniscus, confirming the injury, this patient received arthroscopic suture surgery with excellent results) Surgical time : Generally within 30 minutes. Resumption of walking time: Patients with partial or total excision can usually walk with crutches the next day and walk completely normally in 1-2 weeks. For patients with sutures, it takes about 1 month before the leg on the operated side can partially walk with weight, and 2 months to walk normally. Knee flexion: Generally, there is no difficulty in practicing on your own and you can return to normal within 1 month.