Review Question - QID 211788

This patient sustained a PCL injury. Unlike the transtibial technique, the tibial inlay technique avoids the aggressive 90-degree "killer" turn of the graft as it exits the tibial tunnel.

Injuries to the PCL occur commonly following direct blow to proximal tibia with a flexed knee (dashboard injury), noncontact hyperflexion with a plantar-flexed foot, or a hyperextension injury. The PCL is the primary restraint to posterior tibial translation. Reconstruction is most commonly performed with an allograft via either a transtibial or tibial inlay technique. With the transtibial technique, passage of the allograft may be difficult as it requires a sharp 90-degree turn as it exits the tibial tunnel. This sharp turn in the graft as it emerges from the tibia is believed to lead to more pronounced attenuation and thinning of the graft during cyclic loading. Conversely, the tibial inlay technique utilizes a posteromedial approach to the tibia which allow the graft to be fixed directly to the posterior aspect of the tibia.

Zawodny et al. reported on the unique complications related to PCL reconstruction. They state that these complications are secondary to the relative infrequency of PCL injuries, the lack of knowledge and experience in treating them, the proximity of neurovascular structures to the PCL, and the technically demanding nature of reconstructive procedures. They concluded that proper technique will minimize postoperative complications.

Matava et al. reviews PCL reconstruction. They report biomechanical benefits of the inlay technique of tibial fixation compared with traditional tunnel fixation. However, they conclude that the optimal method of PCL reconstruction can be determined only with continued advances in basic science studies and clinical trials isolating one reconstructive variable.

Voos et al. reviewed the current literature on the anatomy, biomechanics, and clinical outcomes of PCL reconstruction. They report that tibial inlay PCL reconstructions (either open or arthroscopic) are preferred by many due to avoidance of the "killer turn" and graft laxity with cyclic loading. They conclude that PCL reconstruction improves outcomes and return to sport, despite complete restoration of stability and knee kinematics to normal.

Figure A is the sagittal MRI image revealing a PCL rupture. Illustration A depicts a tibial inlay PCL reconstruction. Illustration B depicts the "killer" 90-degree turn with use of a transtibial PCL reconstruction.

Incorrect Answers:
Answers 2-5: Tibial inlay technique has not been found to be superior to transtibial technique for PCL reconstruction with respects to decreased surgical time, rehabilitation, clinical outcomes, or preservation of knee kinematics