Extract
Ligament-balancing techniques are utilized to balance the flexion and
extension gaps of the knee during total knee arthroplasty. Many different
techniques to test for ligament balancing (as well as different structural
release techniques and sequences of structural release) have been
reported1-9.
Distraction testing methods include the use of tension jigs, laminar
spreaders, and spacer blocks or in-line traction to assess the joint gap after
the femoral and tibial bone cuts have been made. This concept was popularized
by Freeman et al.1
and Insall et al.2
and involves distracting the joint space in both flexion and extension to
balance the gaps created when the joint gap is filled with prosthetic
components (Fig. 1). The change
in the shape of the joint gap from flexion to extension has been termed
"gap kinematics," and the goal is to balance these gaps during
total knee
arthroplasty4,5,7.
Another technique for testing ligament balancing utilizes trial components to
fill the gaps followed by application of varus and valgus stresses to test for
laxity of the medial and lateral soft-tissue
sleeves3,8,9.
Whether one utilizes a distraction technique or trial components with
application of varus and valgus stresses to assess soft-tissue balancing, the
knee should be balanced in both flexion and extension.