The improvement of outcomes in posterior cruciate ligament reconstruction: A case for joint biomechanics

The exploration of the pathogeneses of the various musculoskeletal diseases and assessing the efficacy of the respective treatments have, in general, been done using clinical outcomes, combined with static imaging diagnostics that search for damaged tissues. We here argue that for posterior cruciate ligament (PCL) deficiency, an infrequent pathology characterized by a variable natural history and long-term complications, quantifying the normal joint biomechanics and the impact of injury on these biomechanics, and obtaining a clear insight in the efficiency of surgical techniques to reproduce the normal joint biomechanics have the potential of improving the outcomes of the pathology. The biomechanical analysis with a in-vitro robotic testing system and an in-vivo combined magnetic resonance and dual fluoroscopic imaging technique could explain the onset of degenerative changes that are seen in PCL-deficient and PCL-reconstructed knees, define a range of flexion in which rehabilitation exercises might be safely performed, and provide concrete guidelines for the improvement of the surgical reconstruction through optimal graft fixation and orientation.