Just because you tear your ACL does not mean you need surgery. There is a percentage of the population that are able to “cope” and use their muscles to stabilize their knee during activities. The decision to have surgery or not have surgery is ultimately yours to make, but you should take into consideration your age (the younger the more likely you might want to consider surgery), your activity choices (pivoting sports like soccer?), the number of incidences of your knee giving out, and your dedication to your rehabilitation (much more work following ACL reconstruction). This would be a good discussion t o have with both your physical therapist and your surgeon.