Venous Thromboembolic Disease in Revision vs Primary Total Knee Arthroplasty.

BACKGROUND: Venous thromboembolic disease (VTED) is a serious complication of primary and revision total knee arthroplasty (TKA). However, the incidence and risk of VTED for revision compared with primary TKA cases have not been well-described.

METHODS: We identified 225,584 TKAs (208,954 primaries, 16,630 revisions) in the 2003-2012 Statewide Planning and Research Cooperative System database. Odds ratios (ORs) expressed the risk of VTED for revision vs primary TKA, and models were adjusted for age, gender, race, and Charlson comorbidity scores. Outcome analyses were further stratified into deep venous thromboses (DVTs) and pulmonary emboli (PEs).

RESULTS: The incidence of VTED within 30 days was 2.24% for primary and 1.84% for revision. In multivariable-adjusted regression, the OR of VTED within 30 days for revision compared with primary was 0.81 (95% confidence interval = 0.72-0.91; P < .001). The incidence of VTED within 90 days was 2.42% for primary and 2.13% for revision (P = .022), with a multivariable-adjusted OR of 0.87 (95% confidence interval = 0.78-0.97; P = .010) for revision compared with primary. The association was stronger for PE (OR = 0.63; P < .001) than DVT (OR = 0.87; P = .035) at 30 days, and significant for PE (OR = 0.69; P < .001), but not DVT (OR = 0.94; P = .284) at 90 days.

CONCLUSION: In a large statewide database, the risk of VTED was lower for revision TKA compared with primary TKA. The reasons for this observation are not known, but might be related to aggressive prophylactic management of patients undergoing revision procedures. Future studies should attempt to clarify differences in patient selection and management for primary vs revision procedures.