Mortality and perioperative complications after unicompartmental knee arthroplasty

Aim of study: Unicompartmental knee arthroplasty (UKA) has been increasingly utilized over the past decade secondary to favorable reports of better range of motion, higher activity levels, and increased patient satisfaction compared with total knee arthroplasty (TKA). The aim of this study was to determine the 90-day incidence of perioperative complications and mortality of patients undergoing UKA.

Methods: One thousand consecutive UKA in 828 patients were retrospectively reviewed. A retrospective review was performed to evaluate 90-day perioperative complication and mortality rates.

Results: There were zero deaths during the study period. Twelve percent of surgeries were complicated by variances within the 90-day postoperative period. There was one deep venous thrombosis (0.1%) and no pulmonary emboli. Cardiovascular complications were infrequent. Three patients had a myocardial infarction (0.31%), one developed congestive heart failure (0.1%), one angina (0.1%), and three had arrhythmias (0.31%). Secondary procedures were performed in 15 patients during the follow-up period: seven were manipulations under anesthesia for arthrofibrosis, one was an arthroscopic removal of retained cement, one arthroscopic removal of a drain, one repeat wound closure after a dehiscence secondary to a fall, one open reduction internal fixation for a supracondylar femur fracture, three irrigation and debridement procedures for an aseptic hematoma, and one radical debridement with later successful conversion to a total knee arthroplasty for a periprosthetic infection.

Conclusion: This study supports the notion that UKA is a safe procedure that is associated with a low rate of mortality and serious post-operative complications.