Can I forgive my knee for not working right?
Forgiveness concerns people. We offer kindness, respect, generosity, and even love toward those who hurt us. Your knee cannot be willful in deciding to hurt you. You can be kind to yourself as you struggle with the knee, but the knee itself cannot act in an intentionally wrong way or be in a relationship with you in which both of you share inherent worth. You can accept that the knee is not performing well, but to accept and to forgive are not the same.
For additional information, see Forgiveness Defined.