JAAOS - 2026-07-23 - Journal Article
Predictive Factors for Manipulations Under Anesthesia After Total Knee Arthroplasty: An Analysis of 15,139 Cases.
Iyer A, Culler M, Telang S, Palmer RC, Jones IA, Lieberman JR, Heckmann ND
Topics
Key Takeaway
In 975,235 TKAs, 1.55% required MUA within 90 days, with perioperative dexamethasone (aOR 0.925), daily prednisone (aOR 0.433), and ARB use (aOR 0.882) independently reducing MUA risk.
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Summary
This study queried the Premier Healthcare Database (2015–2021) to identify preoperative and perioperative predictors of MUA within 90 days of primary TKA. Mixed-effects modeling identified younger age (62.47 vs. 67.03 years), female sex, and Black race as independent risk factors for MUA, while perioperative dexamethasone (aOR 0.925), daily prednisone (aOR 0.433), and ARB use (aOR 0.882) were protective. The overall MUA rate was 1.55%, consistent with published incidence ranges.
Key Limitation
The database cannot confirm whether dexamethasone and ARB use reflect a direct anti-fibrotic mechanism or serve as proxies for healthier, better-optimized patients with lower baseline inflammatory burden, introducing significant confounding by indication.
Original Abstract
INTRODUCTION
Limited range of motion (ROM) and arthrofibrosis are complications that affect approximately 1 to 13% of patients after primary total knee arthroplasty (TKA). Manipulation under anesthesia (MUA) is the preferred treatment when failure to achieve adequate ROM in the early postoperative period occurs. This study aims to identify predictors for MUA that may guide surgeons in preoperative risk stratification.
METHODS
The Premier Healthcare Database was queried to identify patients aged 18 years or older who underwent elective total knee arthroplasty. Patients who underwent manipulation under anesthesia within 90 days of index surgery were compared with patients who did not. Demographics, comorbidities, and medication usage were compared between cohorts using chi-squared and t-tests. Akaike information criterion and Bayesian information criterion minimization was done to create an optimal mixed-effects model to identify risk factors.
RESULTS
In total, 975,235 TKAs performed between 2015 and 2021 were identified. Of these, 1.55% (15,139) of patients required MUA. Patients in the MUA group were younger (62.47 ± 9.19 vs. 67.03 ± 9.24, P < 0.001) and more likely to be Black (15.91% vs. 8.29%, P < 0.001). Mixed-effects analysis revealed a decreased risk of MUA associated with perioperative dexamethasone (adjusted odds ratio [aOR] 0.925, 95% CI, 0.889-0.962, P < 0.001), daily prednisone usage (aOR 0.433, 95% CI, 0.347-0.542, P < 0.001), and angiotensin II receptor blockers (ARBs) (aOR 0.882, 95% CI, 0.840-0.927, P < 0.001).
DISCUSSION
Younger age, female sex, and Black race were associated with an increased risk of MUA after TKA, while perioperative dexamethasone, daily steroids, and ARB use were protective. These findings may serve to aid surgeons in preoperative risk stratification.