Which Modifiable Risk Factors Should Be Included in Preop Optimization Protocols for TJA Patients?

    Editor’s Note: Research papers intended for presentation at the canceled annual meeting of the American Academy of Orthopaedic Surgeons are now available online at the AAOS Virtual Education Experience. We’ll be highlighting a few of the more interesting papers throughout the summer.

    How well patients do after total joint arthroplasty – whether they’re discharged on schedule, whether they have to be readmitted, whether they develop serious complications – often depends on how well they’re optimized before surgery.

    Dr. Bryan Springer has spoken on this topic many times at ICJR meetings, noting that there are multiple modifiable risk factors, such as encouraging smoking cessation, addressing malnutrition, and controlling the hemoglobin A1c level, that can be addressed preoperatively to help improve outcomes of total joint arthroplasty. In a study published in 2017, Kee et al [1] found that more than 40% of patients who needed an early revision of a total hip or total knee arthroplasty had at least 1 modifiable risk factor.

    The importance of modifiable risk factors is set against the backdrop of constraints in reimbursement and projections of significant increases in primary total joint arthroplasty through 2030, although the COVID-19 pandemic may reduce those projections somewhat. [2-5] So, it’s imperative for surgeons to develop protocols to mitigate risk factors that could increase costly readmissions, reoperations, and revisions in total joint arthroplasty patients.

    But which modifiable risk factors should surgeons prioritize? There are dozens of them, but not all have the same widespread impact on outcomes. Can surgeons look to the literature for guidance when developing protocols for optimizing total joint arthroplasty patients?

    Researchers from VCU Health in Richmond, Virginia, hoped to answer that question with a literature search of PubMed, MEDLINE, EMBASE, CINAHL, and the Cochrane Library databases Their goal: Find studies that that show how optimizing various modifiable risk factors in total joint arthroplasty patients affects clinical outcomes and the bottom line, including:

    • Periprosthetic joint infection (PJI)
    • Revision surgery
    • Hospital length of stay (LOS)
    • Readmission rates
    • Overall cost of care

    Their literature search identified 9 relevant retrospective cohort studies that included 10,184 patients. In evaluating these studies, the researchers found that implementing protocols to optimize total joint arthroplasty patients preoperatively was associated with statistically significant reductions in PJI, hospital LOS, average total cost of care, and hospital readmission rates. 

    They recommend including 7 modifiable risk factors in preoperative optimization protocols, based on their literature review:

    • BMI < 35-40 kg/m2
    • Hemoglobin >11-12 g/dL
    • Glucose control (hemoglobin A1c <7-7.5%)
    • No tobacco use for 30 days prior to surgery
    • MRSA colonization status
    • Nutritional status (albumin >3-3.5 g/dL)
    • CPAP for patients with obstructive sleep apnea

    There are, of course, caveats. The studies the researchers evaluated were all retrospective in nature, the preoperative optimization protocols were heterogeneous, and different thresholds were used for some criteria, such as BMI cutoff of 35 in some studies and 40 in others.

    With that in mind, the researchers said that, “caution must be taken with protocol implementation and strict criterion, as many risk factors are challenging to modify, and such protocols may have potential for denying patients appropriate care. Future prospective study is necessary for further refinement of preoperative optimization protocols.”


    Patel NK, Johns WL, Morrell A, Layon DR, Golladay G,Scott M, Kates SL. Pre-operative Optimization Protocols Targeting Modifiable Risk Factors and Their Role in Total Joint Arthroplasty: A Systematic Review. Paper 488. AAOS Virtual Education Experience.

    Johns WL, Layon DR, Golladay G, Kates SL, Scott M, Patel NK. Preoperative risk factor screening protocols in total joint arthroplasty: a systematic review. J Arthroplasty. 5 June 2020. In press. Published ahead of print.


    1. Kee JR, Mears SC, Edwards PK, Barnes CL. Modifiable risk factors are common in early revision hip and knee arthroplasty. J Arthroplasty. 2017 Dec;32(12):3689-3692. doi: 10.1016/j.arth.2017.07.005. Epub 2017 Jul 14. PMID: 28780223
    2. Kurtz S, Ong K, Lau E, Mowat F, Halpern M. Projections of primary and revision hip and knee arthroplasty in the United States from 2005 to 2030. J Bone Joint Surg Am . 2007 Apr;89(4):780-5.
    3. Sloan M. Premkumar A, Sheth NP. Projected Volume of Primary Total Joint Arthroplasty in the U.S., 2014 to 2030. J Bone Joint Surg Am. 2018 Sep 5;100(17):1455-1460.
    4. Singh JA, Yu S, Chen L, Cleveland JD. Rates of Total Joint Replacement in the United States: Future Projections to 2020-2040 Using the National Inpatient Sample. J Rheumatol. 2019 Sep;46(9):1134-1140.
    5. Bedard NA, Elkins JM, Brown TS. Effect of COVID-19 on Hip and Knee Arthroplasty Surgical Volume in the United States. J Arthroplasty. 2020 Jul;35(7S):S45-S48.