TABLE I.

Frequency of All-Cause and TKA-Specific Readmissions 30 Days After TKA in NY State Between January 1, 1997, and November 30, 2014

		30-Day Readmission Rate
Type of Readmission*	No. of Readmissions	% of All-Cause Readmissions	% (95% CI) of all TKAs ( N = 377,705)
CMS TKA-specific†	2,449	11.1	0.65 (0.62, 0.67)
Expanded TKA-specific‡	6,784	30.7	1.80 (1.75, 1.84)
All-cause§	22,076	100.0	5.84 (5.77, 5.92)

^*Readmission categories are not mutually exclusive.

^†Readmissions due to any of 8 diagnoses designated by the CMS as TKA-specific complications (see Appendix).

^‡Readmissions due to a diagnosis on an expanded list of TKA-specific complications, including 22 additional TKA-specific complications selected by a group of experts (see Appendix).

^§Readmissions due to all causes, including 918 conditions not included in the CMS-defined or expanded list of TKA-specific complications (see Appendix).