Hi- this is Bikash, A Sr PT in India at Bangalore.Yes you asked the right question.In TKR the ligament is not disturbed.Its only artificial light weight prosthesis is being inserted.thats the reason the patient can stand up by evening on the same day with full weight bearing and can do all flexion and extensions.We used to discharge the patient after TKR on the very 5th day at here.If ligament is touched, he or she cant walk for long.thanks.