Multi-factorial analysis of time efficiency in total knee arthroplasty

The objective of this retrospective review was to determine whether time efficiency could be gained by optimizing the navigation protocol based on a surgeon's specific technique and work flow. Three groups of 30 consecutive patients operated on by the same surgeon were studied. The groups were from three distinct periods between 2002 and 2008. The first group consisted of patients in which no navigation was performed (the control group); the second group consisted of patients in which navigation was performed using a standard protocol; and the third group consisted of patients in which navigation was performed using a customized protocol that eliminated certain steps. Statistical analysis considered analysis of variance for covariates of total time in the operating room, duration of the procedure, and tourniquet time. Chi-square analysis considered categorical variables of age, gender, body mass index (BMI), Knee Society score, and patellar resurfacing against the surgical group. Multiple linear regression analysis evaluated surgical time adjusted for preoperative deformity, BMI, and patellar resurfacing. In the adjusted model, the customized navigation protocol significantly reduced the surgical time by 10 minutes compared to the non-customized navigation. Not resurfacing the patella significantly reduced the surgical time by 9 minutes. Variables of age, gender, BMI, preoperative deformity and Knee Society score were not related to differences in operating time. Time efficiency may be gained with the use of improved computer navigation protocols and patellar non-resurfacing.