The present review classifies and describes the multifactorial causes of anterior cruciate ligament (ACL) surgery
failure, concentrating on preventing and resolving such situations. The article particularly focuses on those causes
that require ACL revision due to recurrent instability, without neglecting those that affect function or produce persistent pain. Although primary ACL reconstruction has satisfactory outcome rates as high as 97%, it is important to identify the causes of failure, because satisfactory outcomes in revision surgery can drop to as much as 76%. It is often possible to identify a primary or secondary cause of ACL surgery failure; even the most meticulous planning can give rise to unexpected findings during the intervention. The adopted protocol should therefore be sufficiently flexible to adapt to the course of surgery. Preoperative patient counseling is essential. The surgeon should limit the patient’s expectations for the outcome by explaining the complexity of this kind of procedure. With adequate preoperative planning, close attention to details and realistic patient expectations, ACL revision surgery may offer beneficial and satisfactory results for the patient.
Keywords: ACL reconstruction, ACL revision, Allografts, Autografts, Failure of ACL reconstruction, Instability, Pain,