An elevated ACL thickening signal indicates that there is damage to the ligament; whether it is serious or not cannot be generalized, but depends on the specific injury. Anterior cruciate ligament thickening and increased signal is usually an imaging modality that is observed when a patient undergoes an MRI. During an MRI of the knee, the ACL signal should normally be low, and an increased ACL thickening signal usually means that there is an ACL injury. The higher the signal, the more severe the ACL tear. If an ACL thickening signal is found to be elevated, further physical examination, arthroscopy, joint X-ray, joint ultrasound and other examinations are needed to clarify the specific injury before specific treatment is carried out. Treatments include conservative and surgical treatments. When there is an ACL thickening signal increase, you should promptly cooperate with your doctor for other relevant examinations and actively carry out treatment under the doctor’s guidance.