Does a Torn Cruciate Ligament Always Need Surgery?
In rare cases, cruciate ligament injuries in people who are not very active in sport can be treated conservatively with physiotherapy and muscle-building training. In athletically active patients, surgical revision is now the recommended approach, as untreated injuries often lead to further injuries sooner or later. Damage to the menisci and cartilage layers are consequences that can lead to premature osteoarthritis.
Sources: Dr. Pierre Hofer