Knee Surg Relat Res.  2019 Mar;31(1):12-18. 10.5792/ksrr.18.033.

Preoperative Varus-Valgus Stress Angle Difference Is Valuable for Predicting the Extent of Medial Release in Varus Deformity during Total Knee Arthroplasty

• Lee OS
• Elazab A
• Lee YS

• KMID: 2446715
• DOI: http://doi.org/10.5792/ksrr.18.033

Abstract

PURPOSE
The purpose of this study was to compare the predictive value of the valgus stress angle (SA), varus SA and varus-valgus SA difference (VVD) in predicting the degree of medial release in varus deformity during total knee arthroplasty (TKA).
MATERIALS AND METHODS
One hundred eight TKAs (78 patients), which were performed in primary osteoarthritis with varus knee deformity, were retrospectively classified into three groups according to the degree of medial release (group A, mild release; group B, moderate release; and group C, severe release). Medical charts were reviewed, and long weight bearing standing anteroposterior radiographs and varus-valgus stress radiographs were evaluated.
RESULTS
The valgus SA was significantly different between group A and B and between group A and C. However, it was not significantly different between group B and C. The varus SA was significantly different between group B and C and between group A and C. However, it was not significantly different between group A and B. The VVD was significantly different in all intergroup comparisons.
CONCLUSIONS
Evaluation of the VVD is more valuable in predicting the degree of medial release in TKA performed in varus knee deformity than evaluation of the simple valgus and varus SA.

Keyword

Knee; Arthroplasty; Varus; Varus-valgus stress angle difference; Medial release

MeSH Terms

Arthroplasty
Arthroplasty, Replacement, Knee*
Congenital Abnormalities*
Knee
Osteoarthritis
Retrospective Studies
Weight-Bearing