A long journey to be anatomic

Abstract

In 1836, Weber and Weber from Gottingen, Germany performed dissection studies and described the anterior cruciate ligament (ACL) as two separate bundles that tension at different knee flexion angles [21, 33]. Many years later in 1912, the first ACL reconstruction was performed by Giertz, the mentor of Palmer, using a single-bundle of tensor fascia lata [5]. In 1917, Hey-Groves used an open ACL reconstruction technique that was ‘‘quite’’ anatomic [9]. He used tunnels to locate the graft, drilling the femoral tunnel inside-out, aiming to place the tunnel aperture on the outer aspect of the notch to produce an oblique graft. In 1938, Palmer proposed the idea of double-bundle reconstruction in his thesis on the ACL [20], though the concept received little attention at the time and his work was not appropriately accredited until many years later. The first arthroscopically assisted ACL reconstruction was performed in 1980 by Dandy [4]. However, arthroscopic surgery was far more challenging than open reconstruction. Arthroscopic anatomic reconstruction of the ACL has a learning curve, as Snow et al. demonstrate in their paper [26]. Surgeons and industry started focusing on developing standardized techniques to facilitate easier and more efficient graft placement, employing techniques such as the o0clock reference, notchplasty, isometry and drill guides. Some of these terms like the o0clock reference and isometry turned into almost mandatory but often misleading technical descriptions. The resulting surgical techniques were indeed fast and efficient, but as Behrend et al. [2] show in their study on the over-the-top guide, unable to place the tunnels in the ACL insertion site. It was such techniques that lead the field away from the teachings of Weber, Palmer and their colleagues. Anatomic tunnel placement was not a priority, and the two-bundle anatomy of the ACL was never considered. This had surgeons asking: ‘‘Does anatomy matter?’’ since the general consensus was that these arthroscopic techniques were effective for restoring knee function. However, as longer-term follow-up data and better kinematic analysis techniques emerged, it has become clear that conventional non-anatomic ACL reconstruction techniques do not prevent the development of early osteoarthritis after ACL injury [6, 14, 16] nor do they restore normal dynamic knee function [27]. These results indicate that our reconstruction techniques need to be improved and restoring anatomy may be the key to success. Therefore, efforts to make reconstruction techniques more anatomic as well as critically evaluate them, such as by Silva et al. [24, 25] and Serrano-Fernandez et al. [23], should be applauded. ‘‘Anatomic’’ ACL reconstruction can be defined as the functional restoration of the ACL to its native dimensions, collagen orientation and insertion sites (Fig. 1) [29]. It is a detailed and meticulous procedure that involves visualization of the native ACL insertion site, measuring ACL and knee dimensions, appropriate graft tensioning and evaluation of graft and tunnel position using MRI and 3D CT scan. It encompasses singleand double-bundle reconstruction and can be applied to primary, revision and augmentation surgery. The development of the anatomic technique has made us take a closer look at the ACL anatomy. Just a few years ago, you would not have seen F. H. Fu Department of Orthopaedic Surgery, University of Pittsburgh Medical Center, Kaufman Building Suite 1011, 3471 Fifth Avenue, Pittsburgh, PA 15213, USA