Abstract
Much emphasis has been placed on the role of patella resurfacing in total knee arthroplasty
(TKA), yet the impact of soft tissue balancing has frequently been understated. The
authors used a novel system to precisely assess patellofemoral joint (PFJ) tracking
intraoperatively, to determine the impact of both retinacular reconstruction and tourniquet
use on PFJ kinematics. PFJ kinematics assessed intraoperatively for 20 consecutive
TKA patients. Measurements were recorded using both the “no thumb technique” and following
reconstruction of the retinaculum with two positional sutures. The tourniquet was
deflated and both measurements were repeated. Tourniquet inflation was not found to
have a significant impact on the patella tracking (mean translation 0.9 mm, p = 0.15). Patella retinacular reconstruction generated a significant medialization
of the patella by a mean of 5.5 mm (p < 0.0001) when compared with the traditional retinacular open “no thumb technique.”
The use of a tourniquet has been shown to have no effect on patella tracking. Reconstruction
of the patella retinaculum markedly improves patella tracking, generating a mean medialization
of 15%. The authors advocate the routine use of two positional sutures to restore
the patella retinaculum, before trialing the patella component, as a reproducible
means of assessing the PFJ kinematics.
Keywords
total knee arthroplasty - patellofemoral joint - no thumb technique - retinaculum
- tourniquet
