A hole in the knee requires different treatment depending on the size and depth of the wound. If the knee trauma is not accompanied by limitation of knee movement, mostly caused by soft tissue injury, for wounds that are relatively superficial and small in area, first use hydrogen peroxide as well as saline for wound debridement and disinfection, apply mercury bromide red topically to expose the wound and avoid covering it, and inject tetanus antitoxin after treatment to avoid tetanus bacillus infection. If the wound is relatively deep and large, it needs to be further sutured after clearing treatment, and then disinfected with iodophor and covered with sterile gauze for dressing. If the knee trauma is accompanied by limitation of lower limb movement, further radiographic examination is required to rule out the possibility of knee ligament meniscus injury or fracture and further treatment according to the examination results.