Table 3.

Univariable and multivariable analyses of medical complications after UKA

Variable	RA-UKA (n = 1297)	C-UKA (n = 5857)	Unadjusted P	Adjusted aOR	95% CI	Adjusted P
AKI	12 (0.9)	78 (1.3)	0.235	0.743	0.389–1.419	0.369
Congestive heart failure	12 (0.9)	46 (0.8)	0.611	1.287	0.657–2.523	0.462
Acute heart failure	30 (2.3)	119 (2.0)	0.521	1.244	0.791–1.955	0.344
Stroke	1 (0.1)	3 (0.1)	0.551	–	–	0.996
Pneumonia	0 (0.0)	6 (0.1)	0.600	–	–	0.988

Values are presented as n (%). Unadjusted P values were obtained using chi-square or Fisher’s exact tests, as appropriate. Adjusted odds ratios (aORs) and 95% confidence intervals (CIs) were estimated using multivariable logistic regression adjusted for the covariates listed in Table 1, including calendar year fixed effects (YEAR 2016–2022). “–” indicates that adjusted estimates were not estimable because of sparse events and model nonconvergence; in such cases, the adjusted P value was derived from the Score test and should be interpreted cautiously. Rare events (e.g., stroke and pneumonia) are also summarized descriptively in Supplementary Table S2. RA-UKA, robotic-assisted unicompartmental knee arthroplasty; C-UKA, conventional unicompartmental knee arthroplasty; AKI, acute kidney injury; aOR, adjusted odds ratio; CI, confidence interval