The healing process starts with an injury of any kind from something as simple as a paper cut to something as complex as a torn meniscus. Each time an injury occurs there is a four-phase healing process that takes place so that the body can repair itself.
The first phase is the hemostasis phase which starts within seconds of the injury. The blood vessels in the affect area become smaller to limit the amount of blood loss and the body forms a scab to act as a dam to block any drainage that may occur.

In the second phase inflammation starts with localized swelling around the area impacted. The swelling allows for the healing and repair cells to move to the site and for the damaged and bacterial cells to be removed from the site. During the inflammation phase reddening of the skin, heat and pain are also common symptoms around the area. The third phase is the proliferation stage or the rebuilding stage. In this phase new tissues are made to replace the damaged ones and new blood vessels are formed to support those new tissues. The scab formed in phase one becomes smaller due to the wound contracting as the new tissues are formed.

The last stage of the healing process is the maturation or remolding phase. The tissues are in a disorganized state before the maturation phase which works to organize the tissues along the tension lines of the body to create a strong structure. The swelling from the inflammation phase is reduced in this phase as well due to the body reabsorbing water between the new tissues also helping to strengthen the scar tissue. Even after all of this work the healed wound is still going to be weaker than uninjured tissue. The healing process is an amazing, complicated process that allows us to continue living our life because the human body can repair itself.