It is easier to describe a wound by what it isn't than what it is. It is a trauma that is created by a life experience that is not part of an individual's soul contract. Rather, the wounded person was a target of someone else's malicious energy, whether intentional or unintentional.
You may find that your client was wounded, or was the person who wounded someone else.
Most wounds are from a past life, although we may need to heal wounds from this lifetime as well.
The first thing to recognize is that a person who inflicts a wound upon someone else is doing so because they themselves are affected by trauma that is causing them to lash out.
To heal from a wound, we call upon the Trinity of the Deep, and any other Archangels whom we feel moved to ask, to heal the attacker from the initial trauma that caused them to eventually hurt the victim. At the same time, we request that they extend their healing to anyone else who would have been affected by the attacker beginning from the time of the initial trauma.
Once this is done, there should no longer be a wound. However, the energy is unlikely to be resolved between the attacker and the victim. At this point, check if the attacker is ready to ask for forgiveness from the victim. If the client was the one wounded, the client will need to forgive the past life attacker. If the client caused the wound, assume the past life client is asking the past life victim for forgiveness. Resolve forgiveness as usual.
If the wound was from a past life, follow the instructions exactly as above.
If the wound is in this lifetime, it is impossible to re-write the attacker's past in this reality. Instead, address the two in a parallel universe and heal the trauma and work through forgiveness that way. The final step, however, will require bringing the energy of the client, who is now healed in the parallel universe, into this lifetime.