The Implementation of Lean Six Sigma Principles to Improve the Value of Care Delivery for Total Joint Arthroplasty Patients

The Perioperative Institute of Surgical Excellence Experience

Mouhanad M. El-Othmani, MD; Zachary Crespi, BS; Vinay Pallekonda, MD; Zain Sayeed, MD, MHA; Khaled J. Saleh, MD, MSc, FRCS(C), MHCM, CPE


J Am Acad Orthop Surg. 2021;29(21):e1087-e1096. 

In This Article

Abstract and Introduction


Background: With the projected increase in the volume of total joint arthroplasty (TJA), minimizing variations in surgery times, hospital length of stay (LOS), discharge dispositions, and inhospital complication rates would help reduce costs and improve the quality of care. As the move toward bundle payment models gains further traction, providers will be reimbursed based on the quality and cost associated with the surgical episode. As such, it remains critical to design and implement high-quality cost-effective perioperative delivery care models. Lean Six Sigma (LSS) methodology has been well described in the healthcare field as a superior strategy in designing processes aimed at reducing waste while minimizing error rates. We present an institutional experience with the design and implementation of a LSS quality improvement process specific to the TJA pathway, with a hypothesis of expected decrease in case cancellation rate, inhospital LOS, 30-day readmissions, and inpatient rehabilitation utilization after program implementation.

Methods: In 2017, the Perioperative Institute of Surgical Excellence (PISE) program for lower limb TJA was designed and implemented at our institution over a 4-month duration. The program was designed following LSS principles as a low-cost easily adoptable model with a goal to reduce hospital LOS, case cancellation rate, 30-day readmissions, and inpatient rehabilitation utilization.

Results: A total of 328 patients (128 total hip arthroplasty and 200 total knee arthroplasty) were included in PISE compared with a total of 255 patients (106 total hip arthroplasty and 149 total knee arthroplasty) for the preimplementation cohort. After implementation of the model, and compared with a similar 4-month preimplementation duration, the pilot results revealed an increase in monthly case load by 28.6%, decrease in the 30-day readmission rate by 1.16%, inpatient rehabilitation utilization by 60%, a reduction of the average LOS by 0.8 days, and a case cancellations decrease by 51%.

Conclusion: The implementation of the pilot protocol for PISE within our institution was successful in decreasing LOS, inpatient rehabilitation utilization, 30-day readmission, and case cancellation. Further assessment is needed to ascertain sustainability of the protocol over a longer duration and generalizability of the results at different institutions and surgeons.


Current projections indicate that the prevalence of hip and knee arthroplasty is on the rise, with growth estimations of 71% for primary total hip arthroplasty (THA) to 635,000 in 2030 and 85% for total knee arthroplasty (TKA) to 1.26 million procedures in 2030.[1] Such increases in volumes, coupled with heightened focus on the quality of delivered care in a financially strained environment, places added emphasis on ensuring improved efficiency of care delivery of these procedures.

Recent legislations proposed transition of health care from the traditional volume-based payment model to value-based care, in which financial reimbursements are attached to the quality of delivered care.[2] This legislation, the Medicare Access and Children's Health Insurance Program Reauthorization Act, was passed in 2015 and aimed at improving quality while minimizing the cost of delivered care.[2] Within Medicare Access and Children's Health Insurance Program Reauthorization Act, eligible providers are granted the opportunity to either enroll in the merit-based incentive payment system (MIPS) or one of multiple alternative payment models (APMs).[2]

MIPS is designed to be a budget-neutral program, with high-performing providers receiving bonuses offset through the penalties to underperforming providers.[3] Performance is assessed via a composite score derived from four categories: quality (45%), resource utilization (15%), advancing care information (25%), and clinical practice improvement activities (15%). As the program grows under the Centers for Medicare and Medicaid Services monitoring and supervision, the weight of these categories and other specifics to the program will fluctuate over the next few years based on data-driven assessment and continuous feedback.[3]

In cases where providers elect to remain outside the MIPS system, APMs are offered as alternatives. The bundled payment reimbursement system remains among the most popular and most experimented with APM. The objective of this system is to align all stakeholders involved in the care delivery to provide high-quality, cost-conscious care by providing an advanced pre-set single lump sum for the entire care episode. Because the cost beyond the provided sum will turn into a financial loss shared by the various stakeholders, this promotes cost-savings similarly reinforced by gainsharing between stakeholders across all services provided in the predetermined episode of care.[4] Within musculoskeletal care delivery, and given the aforementioned skyrocketing volumes, the bundled payment model applications to TKA and THA received increased focus because of the care episodes of these procedures hold substantial margin for cost reduction and quality improvement in the preoperative, inhospital, and postacute care phases of the episode.

In an attempt to cater to the shifting focus on efficiency of care delivery models, in which optimal quality and minimal waste and cost are the end goal, the concepts of Lean Six Sigma (LSS) and service lines were introduced and popularized.[2,3] A musculoskeletal service line aims to align the interest of all stakeholders involved in the musculoskeletal care delivery continuum, via defined, well-designed processes.[4] Through agreement and establishment of baseline parameters and variables constituting a target for improvement, institutional alliances, aimed at quality improvement and cost reduction, can be achieved.[5,6] Stemming from the manufacturing industry, Lean, which was developed by Toyota, identifies and eliminates waste through process mapping and redesign, whereas Six Sigma, developed by Motorola, aims to specifically minimize errors to a six standard deviation level, which is equivalent to 3.4 defects per million products.[3] In combination, LSS methodology constitutes an approach to quality improvement that has a proven track record in healthcare literature in improving value of care delivery by detecting and preventing errors, whereas reducing waste and process variations.[3]

The aim of this manuscript was to present our institutional experience with the design and implementation of a quality improvement process, specific to the total joint arthroplasty (TJA) pathway within our musculoskeletal service line, through the establishment of the Perioperative Institute of Surgical Excellence (PISE). Specifically, the achievement of PISE through engagement and alignment of stakeholders, support of administrators, and LSS guided redesign of the surgical pathway, including the preoperative, intraoperative, and postoperative components of care delivery will be briefly described. The results and impact on perioperative clinical and financial outcomes will be presented while emphasizing the various management methodologies implemented and highlighting the importance of multidisciplinary collaboration to enhance value-based patient-centered care. We hypothesize that the establishment and implementation of PISE would lead to an overall decrease in case cancellation rate, inhospital length of stay (LOS), 30-day readmissions, and inpatient rehabilitation utilization in patients undergoing TKA and THA.