Revision after anterior cruciate ligament reconstruction by restoration of the posterolateral bundle

Recurrent instability after primary single-bundle anterior cruciate ligament (ACL) reconstruction is predominantly caused by technical errors. Delayed biological incorporation and traumatic reinjury represent other factors of ACL graft failure. However, there are patients with an intact single-bundle ACL graft complaining of recurrent instability where imaging studies lack inappropriate positioning of the tunnels and other technical errors. This recurrent instability may be caused by an incomplete restoration of the native ACL because biomechanical studies have shown only partial restoration of normal kinematics in single-bundle ACL reconstruction. We present 2 cases of recurrent instability after primary single-bundle ACL reconstruction that demonstrated an intact ACL graft. We performed an augmentation of the intact ACL graft representing the anteromedial bundle by reconstruction of the posterolateral bundle. This novel technique may address a (partially) recurrent instability after primary ACL reconstruction.