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Patient-specific instrumentation for total ankle replacement: The Emperor's new clothes redux

  • Thomas S. Roukis
    Affiliations
    Editor-in-Chief, Foot & Ankle Surgery: Techniques, Reports & Cases (FASTRAC)
    Past President (2014-2015), American College of Foot & Ankle Surgeons
    Clinical Professor, University of Florida College of Medicine-Jacksonville, Department of Orthopaedic Surgery & Rehabilitation, Division of Foot & Ankle Surgery, Jacksonville, Florida
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Open AccessPublished:January 06, 2022DOI:https://doi.org/10.1016/j.fastrc.2022.100153
      I recently had a rather spirited debate regarding primary total ankle replacement (TAR) and pre-operative computed-tomography (CT) scan-based, engineer-provided plans with patient-specific pinning blocks, so-called, “patient-specific instrumentation” (PSI). While we agreed that mal-aligned TAR metallic components are associated with a higher need for revision and overall worse clinical outcomes, we disagreed on the best way to achieve optimal TAR component alignment. I favored standard-reference guide (SRG) use while they exclusively employed PSI.
      Hearing their arguments in favor of TAR PSI, I was reminded of Hans Christian Andersen's famous fairy tale from 1837 “The Emperor's New Clothes” in which two con artists convince the emperor that they make the finest royal clothes but with the catch that the clothes can be seen only by those who are not stupid. The con artists then receive payments for the royal clothes while the emperor parades around in the bare in front of his townspeople. Out of fear of being deemed stupid, everyone in the empire kept silent about the fact that they could not see the emperor's clothes at all until a child states in public that the emperor isn't actually wearing any clothes. Once the child admits aloud that they cannot see the royal clothing on the emperor, everyone finally admits that the emperor has been tricked and that there was never any royal clothing created at all.
      Why was I reminded of this fable? Well, I am amazed at the blind conviction providers hold regarding TAR with PSI based on limited, biased and, in some cases, absent data which can be distilled into an advertisement used to steer patients to the TAR PSI company's websites and ultimately to corporate aligned surgeons. I feel like the child in the fable seeing the truth while everyone else remains “pluralistically ignorant”. Why don't I believe? Well for one, the exponential growth of TAR PSI has led to a generation of foot & ankle surgeons unable to use SRG. Unfortunately, the US Food & Drug Administration “Manufacturer and User Facility Device Experience” describes multiple reports of TAR PSI being abandoned and the surgeons needing to convert to SRG in order to complete the TAR. Second, until mid-2021 only one company provided TAR PSI in the US. This company has three TAR systems with some modularity between them but their offerings simply cannot address every patient with end-stage ankle arthritis. Third, in order to justify the time and financial costs associated with a technique that seeks to reduce the TAR prosthesis selection to one of only a few company's while also shifting the balance of surgical planning away from the surgeon to the manufacturer employed-engineer, TAR PSI systems must be able to demonstrate significant and consistent advantages over SRG use which they simply do not. Finally, meaningful cost analysis should include the entire TAR experience starting with the initial patient consultation and terminating at the completion of surgery rather than selectively excluding portions that may not favor CT scan-based TAR planning systems.
      At the present time, despite more than 21,000 TAR performed with PSI in the US
      • Penner MJ
      • Berlet GC
      • Calvo R
      • et al.
      The demographics of total ankle replacement in the USA: a study of 21,222 cases undergoing pre-operative CT scan-based planning.
      and the allure of the manufacturers claims of less procedural complexity, less intra-operative radiation exposure for operating room participants and reduced surgical time with the use of TAR PSI, these theoretical benefits remain a matter for conjecture. The same holds true for primary total hip
      • Henckel J
      • Holme TJ
      • Warwick R
      • Skinner JA
      • Hart A.
      3D-printed patient-specific guides for hip arthroplasty.
      knee

      Thienpont E, Schwab PE, Fennema P. A systematic review and meta-anlalysis of patient-specific instrumentation for improving alignment of the components in total knee replacement. Bone Joint J 96-B:1052-1061; https://doi.org/10.1302/0301-620X.96B8.33747

      • Kosse N
      • Heesterbeek PJC
      • Schimmel JJP
      • van Hellemondt GG
      • Wymenga AB
      • Defoort KC.
      Stability and alignment do not improve by using patient-specific instrumentation in total knee arthroplasty: a randomized controlled trial.
      • Abane L
      • Zaoui A
      • Anract P
      • Lefevre N
      • Herman S
      • Hamadouche
      Can a single-use and patient-specific instrumentation be reliably used in primary total knee arthroplasty? A multicenter controlled study.
      • Kizaki K
      • Shanmugaraj A
      • Yamashita F
      • et al.
      Total knee arthroplasty using patient-specific instrumentation for osteoarthritis of the knee: a meta-analysis.
      and shoulder
      • Lau SC
      • Keith PPA.
      Patient-specific instrumentation for total shoulder arthroplasty: not as accurate as it would seem.
      ,
      • Cabarcas BC
      • Cvetanovich GL
      • Gowd AK
      • Liu JN
      • Manderle BJ
      • Verma NN.
      Accuracy of patient-specific instrumentation in shoulder arthroplasty: a systematic review and meta-analysis.
      replacement. It is noteworthy that the interest in PSI for total hip, knee and shoulder replacement peaked in the early 2010’s and has essentially been abandoned. Simply stated, PSI technology does not replace the need for joint replacement surgeons to master SRG techniques. Ultimately, manufacturer marketing should use caution when advocating one TAR systems superiority over another as the data for all PSI technology remains unproven or potentially succumb to the same fate as PSI used for other orthopaedic joint arthroplasty.
      So, now what? Well, I am encouraging interested readers to submit to FASTRAC manuscripts and/or videos that will help us understand the read world good, bad, ugly, obscene and limits of TAR performed with PSI and SRG. Through sharing your experiences, you can help all interested FASTRAC readers grow as a TAR surgeon and ultimately help our patients receive better care.

      References

      1. https://en.wikipedia.org/wiki/The_Emperor%27s_New_Clothes; Accessed November 15, 2021

      2. https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfmaude/results.cfm?start_search=1&productcode=&productproblem=&patientproblem=&devicename=&modelNumber=&reportNumber=&manufacturer=&brandname=prophecy&eventtype=&reportdatefrom=01%2F01%2F2012&reportdateto=07%2F31%2F2021&pagenum=10; Accessed November 15, 2021

        • Penner MJ
        • Berlet GC
        • Calvo R
        • et al.
        The demographics of total ankle replacement in the USA: a study of 21,222 cases undergoing pre-operative CT scan-based planning.
        Foot Ankle Orthopaed. 2020; 5https://doi.org/10.1177/2F2473011420S00381
        • Henckel J
        • Holme TJ
        • Warwick R
        • Skinner JA
        • Hart A.
        3D-printed patient-specific guides for hip arthroplasty.
        J Am Acad Orthop Surg. 2018; 26: e342-e348
      3. Thienpont E, Schwab PE, Fennema P. A systematic review and meta-anlalysis of patient-specific instrumentation for improving alignment of the components in total knee replacement. Bone Joint J 96-B:1052-1061; https://doi.org/10.1302/0301-620X.96B8.33747

        • Kosse N
        • Heesterbeek PJC
        • Schimmel JJP
        • van Hellemondt GG
        • Wymenga AB
        • Defoort KC.
        Stability and alignment do not improve by using patient-specific instrumentation in total knee arthroplasty: a randomized controlled trial.
        Knee Surg Sports Trauma Arthrosc. 2018; 26: 1792-1799
        • Abane L
        • Zaoui A
        • Anract P
        • Lefevre N
        • Herman S
        • Hamadouche
        Can a single-use and patient-specific instrumentation be reliably used in primary total knee arthroplasty? A multicenter controlled study.
        J Arthroplasty. 2018; 33: 2111-2118
        • Kizaki K
        • Shanmugaraj A
        • Yamashita F
        • et al.
        Total knee arthroplasty using patient-specific instrumentation for osteoarthritis of the knee: a meta-analysis.
        BMC Musculoskel Disord. 2019; 20: 561https://doi.org/10.1186/s12891-019-2940-2
        • Lau SC
        • Keith PPA.
        Patient-specific instrumentation for total shoulder arthroplasty: not as accurate as it would seem.
        J Shoulder Elbow Surg. 2018; 2: 90-95
        • Cabarcas BC
        • Cvetanovich GL
        • Gowd AK
        • Liu JN
        • Manderle BJ
        • Verma NN.
        Accuracy of patient-specific instrumentation in shoulder arthroplasty: a systematic review and meta-analysis.
        JSES Open Access. 2019; 3: 117-129