ABSTRACT
The primary healing potential of anterior cruciate ligament (ACL) has been reported to be extremely poor in clinical and experimental studies. Most authors believe that the ACL does not heal spontaneously after rupture. In 1998, Kurosaka et al. reported two cases of a spontaneously healed torn ACL after non-surgical treatment; only a few cases have been reported. There are some reports of the spontaneously healed ACL or good clinical results after an ACL rupture in a conservative treatment group, but most studies were done by follow-up MRI or the clinical scores. This study experienced a case of spontaneous healing of a ruptured ACL confirmed by magnetic resonance imaging and arthroscopy. This paper reports a case with a review of the literature.