Unicompartmental Knee Arthroplasty for ALL Patients?

Multicenter research is suggesting that surgeons might consider doing a unicompartmental knee arthroplasty in all patients. The study, “Cost-Effectiveness of Surgical and Nonsurgical Treatments for Unicompartmental Knee Arthritis: A Markov Model,” is published in the October 3, 2018 issue of The Journal of Bone and Joint Surgery.

Antonia Chen, M.D., M.B.A., with the department of orthopedics at Brigham and Women’s Hospital, Harvard Medical School in Boston, Massachusetts, told OTW, “In this era of value driven care, it is important to assess surgical and nonsurgical options with regards to their cost-effectiveness. With younger patients undergoing arthroplasty surgery, and longer life expectancy of patients, it is important to understand the most cost-conscious manner of treating our patients to provide them with a high quality of life while reducing costs to society. This modeling study was able to evaluate a larger breath of patients, and assess which approach was ideal for treating patients with unicompartmental knee arthritis.”

For the study, the authors used a Markov decision analytic model which “assessed how lifetime costs and quality-adjusted life years (QALYs) vary as a function of age at the time of initial treatment (ATIT) of patients with end-stage unicompartmental knee osteoarthritis undergoing TKA [total knee arthroplasty], UKA [unicompartmental knee arthroplasty], and NST [nonsurgical treatment].”

“A Markov decision process is a discrete time stochastic control process. It provides a mathematical framework for modeling decision making in situations where outcomes are partly random and partly under the control of a decision maker,” as defined by Wikipedia.

Dr. Chen said that the team “found that unicompartmental knee arthroplasty was universally the best treatment option for unicompartmental knee arthritis until the age of 87.”

“Quality-adjusted life years was higher at all ages, but surgical intervention with unicompartmental knee arthroplasty was only cost-effective until the age of 87 years. Surgical intervention with total knee arthroplasty was only cost-effective until 81 years old. At the age of 70 years, the costs of surgical treatment exceeded the costs of nonsurgical treatment, but the large benefit from surgical treatment resulted in an incremental cost-effectiveness below the willingness-to-pay threshold.”

“The most interesting take-home message from this work is to not discount surgical management in younger and older patients suffering from unicompartmental knee arthritis. Additionally, consider doing a unicompartmental knee arthroplasty in all patients, if possible.”