[Soft tissue management in knees with varus deformity. Computer-assisted sequential medial ligament release].

BACKGROUND

Knees with severe varus deformities and contractures of the medial and lateral collateral ligaments and the posterior capsule require special soft tissue management to gain a stable knee over the full range of movement. The introduction of navigation systems into knee surgery has now made precise measurement of the leg axis and gap size possible.

METHODS

Ten knee joints received a computer-assisted total knee replacement (Ci navigation system DePuy) I-Orthopaedics, Munich). The change of the leg axis and the size of the mediolateral gaps were measured and documented when performing a standardized medial ligament release sequence.

RESULTS

We found a significant effect after each release step regarding the change of the leg axis as well as the gap width (p<0.001). The highest effect was seen for the 6-cm capsule release in extension and the release of the medial collateral ligament in 90 degrees flexion.

CONCLUSION

Implementation of computer-assisted navigation facilitates visualization and quantification of the effect of the sequential medial soft tissue release in total knee arthroplasty.