Summary

Severe OA was strongly associated with patient dissatisfaction following medial opening wedge HTO with current rigid locking plate.

Abstract

Introduction

Changes in demographics and physical activities of younger population have increased the number of patients with medial unicompartmental knee osteoarthritis (OA) requiring surgical intervention. The medial opening- wedge high tibial osteotomy (HTO) is established treatment options in this clinical scenario, and the use of HTO is steadily increasing in Korea. In addition, recent advances in technology and understanding of the surgical techniques have improved clinical
outcomes and longevity, the indications for HTO have expanded. However, factors associated with dissatisfaction following HTO remain unclear. Thus, we (1) identify risk factors for dissatisfaction following HTO; and (2) determine how these factors are affecting patient reported outcome measures (PROMs).

Methods

We retrospectively reviewed the medical records and radiographs of consecutively enrolled 64 medial opening-wedge HTOs. Preoperative demographics, physical activity levels, varus deformity status, degree of osteoarthritis (OA) and intraoperative findings including articular cartilage and meniscus status were recorded. Postoperative radiographs
including alignment, correction amount and weight loading line (WLL) ratio and PROMs including pain VAS, Western Ontario and McMaster Universities Osteoarthritis Index score (WOMAC), and patient satisfaction, were assessed. Patients were categorized into satisfied or dissatisfied group by satisfaction score. Patient and surgical factors were compared and PROMs were compared by the identified predictors.

Results

Of the 64 patients, 45 (70%) satisfied their results, but 19 (30%) did not. Univariate comparisons revealed that only frequency of severe OA (Ahlback > 2) was different between the satisfied (9%) and dissatisfied (47%) group (p<0.01). There were no between-group differences in patient demographics, combined procedure and postoperative alignment
(p>0.1 in all comparisons). Multivariate logistic regression analysis revealed that risk for dissatisfaction was increased 9- fold for Ahlback > 2 severe OA (OR, 9.225; 95% CI, 2.4 to 36.1, p<0.01). Severe OA increased pain VAS and decreased satisfaction of all kinds of activities in patients underwent HTO (p<0.05 in all comparisons).

Discussion And Conclusion

Although recent advances in technology and technique improved functional outcome and longevity of HTO, one third of patients may not satisfy their results. Severe OA was strongly associated with patient dissatisfaction following medial opening wedge HTO with current rigid locking plate. Surgeon should take into account for realizing patient expectation before HTO in patient who has severe OA.