There are 4 important ligaments in each knee: 2 cruciates and 2 collaterals. So depending on which ligament is injured, the treatment and prognosis varies. There are different grades of ligament injuries - the prognosis varies accordingly. it is best to see an orthopaedic surgeon to see which ligament is affected and to what extent. The cruciates are usually full thickness tears and not repairable. In that case, reconstruction (operation) may be required. These tears may not necessarily affect married life.