Process Mapping Total Knee Arthroplasty: A Comparison of Instrument Designs.

BACKGROUND: Total knee arthroplasty (TKA) is commonly performed with proprietary, manual instrumentation provided by the surgical implant manufacturer. Registry studies and meta-analysis, with few outliers, have consistently shown similar functional outcomes and implant survival after TKA regardless of implant manufacturer, implant design, or surgical technique. We hypothesized that process mapping could identify areas for improvement in TKA instrumentation. METHODS: Seventeen TKA implant systems from 10 companies representing over 90% of all TKAs performed in the United States were evaluated. Instrumentation required for femoral, tibial, and patellar preparation was compared. The number of steps including surgical technician assembly steps, instrument handoffs, and surgeon steps were tabulated based off application of a standardized surgical flow, adjusted for manufacturer-recommended steps during completion of a TKA operation. RESULTS: Cruciate-retaining (CR) knee instrumentation in studied systems required 158-225 discrete steps and posterior-stabilized (PS) knees required 181-230 steps. With the fewest steps for femoral, tibial, and patellar instrumentation, CR and PS knee systems could be improved to 145 and 163 steps, respectively. The Arthrex iBalance and the Biomet Vanguard Microplasty required fewest steps among CR systems; the OrthoDevelopment Balanced and the Corin Unity required fewest steps among PS systems. CONCLUSIONS: Process mapping identified potential areas for improved instrumentation in all studied systems, suggesting the possibility to reduce operative steps broadly across the TKA industry. Patient outcomes were not evaluated by system. Future implant system design changes may do well to reduce unnecessary steps and instrumentation.

Reducing cost drivers in total joint arthroplasty: understanding patient readmission risk and supply cost.

Introduction: Understanding and planning for the factors that impact supply cost and unplanned readmission risk for total joint arthroplasty (TJA) patients is helpful for hospitals at financial risk under bundled payments. Readmission and operating room supply costs are two of the biggest expenses. Methods: Logistic and linear regressions are used to measure the impacts of TJA patient attributes on readmission risk and supply costs, respectively. Results: Patients' health market segment and the number/type of comorbidity impacts 30/90-day readmission rates. Surgeon implant preference and type of surgery impact supply costs. Discharge location and two of the five health market segments increase the odds of 30-day readmission. Arrhythmia and lymphoma are the primary comorbidities that impact the odds of readmission at 90 days. Conclusions: Preoperatively identifying TJA patients likely to have large supply costs and higher readmission risk allows hospitals to invest in low-cost interventions to reduce risk and improve healthcare value.