2021 ISAKOS Biennial Congress Paper
Higher Survival Rate Of Total Knee Arthroplasty After High Tibial Osteotomy Compared With Unicompartmental Knee Arthroplasty; A Study Of A Nationwide Cohort Data In Korea
Sun-Ho Lee, MD, Hwasun-gun KOREA, REPUBLIC OF
Jong-Keun Seon, MD, PhD, Prof, Gwangju, Jeonnam KOREA, REPUBLIC OF
Eun-Kyoo Song, MD, PhD, Prof., Gwangju KOREA, REPUBLIC OF
Chonnam National University Hwasun Hospital, Hwasun-gun, Jeollanam-do, KOREA, REPUBLIC OF
FDA Status Not Applicable
Summary
Orthopedic surgeons should be aware of the risk of a relatively low survival rate in TKA after UKA compared to TKA after HTO
Abstract
Background
Although some studies reported that survival rates of TKA after HTO or UKA is not as good as those of primary TKA, but it is still controversial issue regarding survival rate of them. This study was to evaluate the revision rates of TKA after HTO and UKA compared with those of primary TKA and compare survival rate and perioperative complication between TKA after HTO and UKA using propensity score matching analysis.
Methods
List of patients with primary TKA, TKA after UKA or TKA after HTO were obtained from Korean National Health Insurance database for 684,767 TKAs performed from January 1, 2007 to May 31, 2019. Among them, 608,871 cases of the primary TKA due to degenerative OA (Group A), 2,757 TKAs after HTO (Group B), and 1584 TKAs after UKA (Group C). Revision rates were compared between groups with use of log-rank tests and were presented as Kaplan-Meier curves. The adjusted hazard ratio (HR) and 95% confidence interval (CI) of Group B and C compared with reference group (Group A) were calculated for revision rate using a multivariable Cox proportional hazard regression model. 1356 of matched patients were assigned to each group B and C on the basis of propensity score for comparing revision rates until 8 years after TKA and perioperative complication between TKA after HTO and UKA.
Results
The overall revision rate was 1.41% in Group A, 1.74% in Group B, and 3.79% in Group C. The revision rate until 8 years after TKA was significantly higher in Group B or C than in Group A (p<0.001). The multivariable regression analysis revealed that HR for revision compared with Group A rate was significantly higher in Group B and C (1.51 in Group B and 3.97 in Group C). The result of comparison using PSM between TKA after HTO and UKA, TKA after HTO showed lower risk of revision than TKA after UKA (HR: 0.11 at 4 years and 0.22 at 8 years). However, there were no statistical differences in perioperative complications between two groups except incidence of DVT and surgical site infection.
Conclusions
Patients with TKA after UKA or HTO showed significantly higher risk of revision than primary TKA. While TKA after HTO showed lower risk of revision than TKA after UKA, there were no differences in perioperative complications between TKA after UKA or HTO. Thus, surgeons must be aware of the risk relatively low survival rate in TKA after UKA or HTO, especially in TKA after UKA.