After a knee sprain, recovery time depends on the extent of the injury to the knee after the sprain, which may take about 4 weeks in mild cases and up to 2 months or more in severe cases. The anatomy of the knee is complex and a sprain may cause damage to the ligaments and meniscus around the knee. If the sprain is only a soft tissue injury or a mild tear of the ligaments around the knee, the recovery is relatively quick, with most recovering in 4 weeks. Most 1st degree and 2nd degree ligament tears and 1st degree and 2nd degree meniscus injuries can be treated conservatively with a recovery period of about 8 weeks. However, in the case of 3rd degree ligament tears and 3rd degree meniscus injuries, surgery is required and most of them can recover well only 2 months after surgery. For knee sprains, MRI and systematic examination need to be performed promptly after the trauma to determine the treatment plan according to the degree of trauma and promote early recovery.