Anatomic anterior cruciate ligament reconstruction - current evidence and future directions

Abstract: Injury to the anterior cruciate ligament (ACL) is one of the most common orthopedic diagnoses. It is also one of the most researched areas in orthopedic surgery, with well over eleven thousand publications. Despite this, the solution for the best reconstructive technique is still not known and patients still suffer from their injury in both the short- and the long-term. An assessment of the outcomes was performed on randomized clinical trials. In terms of rehabilitation, a postoperative knee brace did not affect the clinical outcome and closed kinetic chain exercises produced less anteroposterior laxity and better subjective outcomes than open kinetic chain exercises. In terms of graft type, the patellar tendon graft produced initially more anterior knee pain and kneeling pain than the hamstring tendon graft. Moreover, the harvest site affected muscle strength initially and the hamstring tendon graft produced more tunnel widening. In terms of surgical technique, double-bundle ACL reconstruction produced less rotatory laxity than single-bundle. Finally, bioabsorbable screws and titanium screws produced equal clinical outcome. An analysis and systematic review was performed on studies of primary ACL reconstruction. This analysis revealed that most therapeutic studies were of a low level of evidence and that the most common study type was case series. The three most common represented journals were Arthroscopy, Knee Surgery Sports Traumatology Arthroscopy and The American Journal of Sports Medicine. Furthermore, there was a correlation between the journals’ impact factor and the mean level of evidence and there was a higher mean level of evidence over time. Anatomic ACL reconstruction is currently one of the modern techniques for ACL reconstruction. This shift in paradigm has created confusion about the term “anatomic”. Two systematic reviews assessed surgical data from studies claiming anatomic ACL reconstruction. The reviews revealed substantial under-reporting, making it difficult to do valid interpretations of the outcomes. A current concepts article was therefore published, outlining the concepts of anatomic ACL reconstruction, including principles and a definition: the functional restoration of the ACL to its native dimensions, collagen orientation and insertion sites. Ultimately, a scoring system was developed for the objective grading of surgical methods in studies of anatomic ACL reconstruction. This scoring system was subsequently implemented in studies comparing single- and double-bundle ACL reconstruction, which revealed means of the score well below a proposed minimum. In summary, a thorough analysis and review of what constitutes an anatomic ACL reconstruction was done, and an assessment was performed on studies comparing single- and double-bundle ACL reconstruction and studies claiming anatomic ACL reconstruction.