Bony morphologic factors affecting injury risk, rotatory stability, outcomes, and re-tear rate after anterior cruciate ligament reconstruction

Jeremy M. Burnham, Thomas Pfeiffer, Jason J. Shin, Elmar Herbst, Freddie H. Fu


A growing body of evidence has demonstrated that factors contributing to anterior cruciate ligament (ACL) injury risk are multifactorial. Recent studies have suggested that bony morphologic features play a sizeable role in this injury risk. Posterior tibial slope and posterior femoral condyle characteristics have been correlated to rotatory knee stability. Tibial slope, increased posterior femoral condylar depth, deepened lateral femoral notch, and intercondylar notch morphology have all been associated with increased ACL injury risk, and in some cases ACL reconstruction failure rates. It is crucial that surgeons understand the influence of these factors on ACL injury and their implications in ACL reconstruction. In select cases, these bony factors can be modified (e.g., osteotomy to decrease the tibial slope). In other cases, surgical, rehabilitation, and return to play strategies may need to be altered (e.g., close evaluation for lateral meniscal tears in the setting of deepened lateral femoral notch, careful graft choice and positioning in the setting of a narrow intercondylar notch). In summary, careful assessment and understanding of bony morphology is paramount to optimizing ACL reconstruction outcomes.