TPLO - influence of locking implants on complications and outcome

Locking TPLO plates are now widely available from numerous different manufacturers and, at least theoretically, provide several advantages in comparison to conventional, non-locking TPLO plates. However, the locking plates are typically more expensive and so a clinically relevant question is whether there are any true benefits of locking TPLO plates that warrant thei extra cost associated with their use.

The most obvious potential advantage of using locking TPLO plates is the extra mechanical stability they might provide. In turn, TPLO plates might decrease change in tibial plateau following surgery or the incidence of catastrophic mechanical failure. Although these advantages might be true, there are relatively few data to definitively demonstrate that this is the case. One ex vivo cadaveric mechanical study demonstrated that the mean loads to failure were higher with locking plates than non-locking plates [1]. Similarly, another ex vivo study demonstrated that the same locking plate provided greater stiffness when loaded axially in comparison to the Slocum plate [2]. Yet another study demonstrated that use of locking plates with locking screws induce less translation of the proximal tibial fragment than use of the locking plate with non-locking screws [3]. However, that same study failed to demonstrate any difference in construct stiffness or cycles to failure when loaded axially depending upon whether locking or non-locking screws were used [3]. [...]