A Biomechanical Comparison of Posterior Cruciate Ligament Reconstruction Techniques

Abstract

Most posterior cruciate ligament reconstruction techniques use both tibial and femoral bone tunnels for graft placement. Because of the acute angle the graft must make to gain entrance into the tibial tunnel, abnormal stresses are placed on the graft that could lead to graft failure. An alternative technique for posterior cruciate ligament reconstruction involves placement of the bone plug from the graft anatomically on the back of the tibia (inlay), preventing formation of an acute angle at the tibial attachment site. We used six pairs of human cadaver knees to compare the biomechanical properties of these two techniques. One knee from each pair underwent tunnel reconstruction while the other knee underwent inlay reconstruction. There was significantly less anterior-posterior laxity in the inlay group when compared with the tunnel group from 30 degrees to 90 degrees of knee flexion and after repetitive loading at 90 degrees of knee flexion. Evaluation of the grafts revealed evidence of mechanical degradation in the tunnel group but not in the inlay group. The inlay technique resulted in less posterior translation with less graft degradation than did the tunnel technique for posterior cruciate ligament reconstruction.

Is the All-arthroscopic Tibial Inlay Double-bundle PCL Reconstruction a Viable Option in Multiligament Knee Injuries?

“…This technique was called into question given the ''killer turn'' imposed on the PCL graft at the aperture of tibial tunnel. The killer turn was associated with friction, graft stretch, and fatigue failure [4,[31][32][33]56]. Although some clinical studies have not found a difference between the transtibial and open inlay techniques [2,29], there is also a body of literature to suggest unsatisfactory results with residual laxity given the transtibial technique [10,21,25,53].…”

Effects of the posterior cruciate ligament reconstruction on the biomechanics of the knee joint: a finite element analysis

“…These PCL reconstruction techniques (single graft and double graft reconstructions) have been compared in previous experimental studies (Bergfeld et al, 2001;Hagemeister et al, 2002;Mannor et al, 2000;Race and Amis, 1996;Race and Amis, 1998;Stahelin et al, 2001). Harner et al (2000b) have shown that the kinematics behavior of a knee with a ''native'' PCL and a knee with double graft reconstructed PCL were similar.…”

CORR Insights®: No Clinically Important Difference in Knee Scores or Instability Between Transtibial and Inlay Techniques for PCL Reconstruction: A Systematic Review

“…The early biomechanical studies opposing PCL transtibial and inlay techniques have shown that the inlay technique was superior in restoring the posterior stability after PCL reconstruction [1,12]. While these differences were observed in a cadaveric model, these results did not ultimately translate into superior clinical outcomes.…”