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SECTION I: SYMPOSIUM: Papers Presented at the 2006 Meeting of the Knee Society

Internet Promotion of MIS and CAOS in TKA By Knee Society Members

Callaghan, John, J; Warth, Lucian, C; Liu, Steve, S; Hozack, William, J; Klein, Gregg, R

Section Editor(s): Laskin, Richard S MD, Guest Editor

Author Information
Clinical Orthopaedics and Related Research: November 2006 - Volume 452 - Issue - p 97-101
doi: 10.1097/01.blo.0000238819.33154.95

Abstract

Total knee arthroplasty (TKA) has developed into one of the most successful treatments in orthopaedics. Numerous long-term followup studies report extremely high clinical success rates (72-100% at 10-20 years) with respect to pain reduction, functional improvement, and overall patient satisfaction.5,8,15,17,19 Many surgeons have been in search of techniques to further reduce recovery time and postoperative pain while maintaining the excellent outcomes of traditional methods and potentially reducing the small percentage of failures. Minimally invasive surgery (MIS) and computer-assisted orthopaedic surgery (CAOS) for total knee arthroplasty (TKA) have recently created much debate by attracting attention from orthopaedic surgeons and patients.3,7,12,16,18,22-25 Despite the rapid emergence and promotion of MIS and CAOS TKA, few studies establish the long-term safety and efficacy.1,3,14,16,23,24 Proponents of MIS and CAOS commonly suggest quicker recovery, less blood loss, decreased soft issue trauma, less postoperative pain, improved cosmetic outcomes, and better knee alignment.3,7,10,12,22 However, these claims have not been adequately substantiated in the scientific literature to justify widespread promotion.

Opponents of MIS and CAOS TKA emphasize apprehension regarding possible complications and long-term outcomes.6,14,18,25 Despite the overall lack of research, the orthopaedic industry has excessively marketed these techniques.4 Surgeons of various experience and skill levels are advertising and making claims about MIS and CAOS TKA on websites.

It is the responsibility of members of the Knee Society to disseminate accurate information and, with this in mind, our study had a dual purpose: (1) to analyze the extent of information available via Internet sites associated with Knee Society members regarding MIS and CAOS TKA; and (2) to evaluate how this information may be interpreted by potential patients as an endorsement of these newer techniques.

MATERIALS AND METHODS

We searched the Internet for personalized websites associated with each member listed on the 2005 membership list of 91 active Knee Society members. We used the search engines Google, Yahoo, and Excite with the physician's name as the main keyword. Affiliations and information such as practice, clinic or hospital name, and location were used as search parameters.

After the initial search we examined likely websites for seven criteria: physician picture, biosketch, contact information, affiliations, specialty, certification/education, and interests/research. If at least four of the seven criteria were found on the website it was categorized as a primary site and included in the study. Each primary website was then evaluated for information regarding MIS and CAOS TKA. We used a data collection questionnaire consisting of 21 questions (Appendix 1) to document specific keywords reported when discussing MIS and CAOS TKA. This questionnaire was a modification of the methodology used in a previous study concerning MIS hip surgery.13 Each claim/keyword mentioned on the website supporting data was classified as: none, unpublished data, or published/peer reviewed data. If published data was cited then the manuscript was obtained to evaluate peer review status.

MIS and CAOS TKA information was often found on institutional websites linked to primary physicians' websites. Therefore, we made an effort to distinguish between claims made by a physician versus claims associated with the physician but endorsed only by an institution. Claims found on primary physician websites were classified as direct because these statements are interpreted as being endorsed by the surgeon. A claim associated with secondary links leading away from the physician website was considered indirect because such information was less likely to be interpreted as endorsed by the surgeon unless the physician was specifically cited. To our knowledge, there is no precedent outlining “primary” websites or making the distinction between “direct” versus “indirect” information contained therein. We chose to frame our study using these definitions in order to minimize arbitrary evaluation of surgeon sites and to address the discrepancy between what information surgeons promote versus information with which they are merely associated. We understand in some cases surgeons are not necessarily responsible for all information contained on what we define as “primary” surgeon sites; however, as our study is oriented around the patients' perspective, we feel these concrete definitions help validate our conclusions and promote the reader's understanding of our study design.

RESULTS

Eighty of 91 Knee Society members (88%) had primary websites. Of these members, 10 had two primary sites and one had three primary sites, for a total of 92 total websites.

Twenty of 92 sites (22%) made indirect reference to MIS TKA, while only 10 of 92 (10.9%) made direct reference to MIS TKA. Of the 20 indirect sites referencing MIS TKA, 18 of 20 (90%) suggested a faster recovery after an MIS procedure. Of the 10 direct sites referencing MIS TKA, five of 10 (50%) suggested a quicker recovery after an MIS procedure. Only two of 20 (10%) indirect sites and one of 10 (10%) direct sites referenced data to substantiate claims made concerning recovery time. No site specifically referenced published or peer-reviewed data. Specific risks associated with MIS were discussed on seven of 20 (35%) indirect sites, and on only two of 10 (20%) direct sites. CAOS TKA was discussed on six of 92 (6.5%) indirect sites and on five of 92 (5.4%) direct sites.

DISCUSSION

Minimally invasive surgery (MIS) and computer-assisted orthopaedic surgery (CAOS), has led to intense publicity in recent years. Personal computers are a gateway to an unprecedented quantity of medical information via the Internet, but the quality of information is often uncertain and unsubstantiated. The promise of quicker recovery time with less pain, less unsightly scarring, and better alignment (claims which have in part been perpetuated on the Internet) have motivated patients to explore the possibility of receiving MIS and CAOS TKA. As a result, orthopaedic surgeons frequently encounter patients who request replacement surgery through smaller incisions with novel (CAOS) and less invasive (MIS) procedures.

We note several limitations to our study. The dates of our data collection were 2/2005-3/2005. This snapshot of MIS and TKA promotion is a potential limitation given the Internet is a dynamic entity, and all information on physician websites is subject to constant change. It is likely MIS and TKA promotion on the Internet continues to rise, but without previous studies for comparison we cannot make a definitive claim concerning current trends. Additionally, one assumption of our study is a lay patient could potentially associate the presence of MIS and CAOS information on what we define as a primary site as an endorsement by the surgeon. While we feel this is logical, such an assumption introduces another limitation, as we did not survey patients to validate their beliefs concerning MIS and CAOS TKA promotion.

Bhattycharyya2 evaluated claims made in orthopaedic print advertisements and found only 14% of the claims were well-supported by data, and exaggeration was common. As more patients gain access to the Internet, it becomes even more important for members of the orthopaedic community to ensure the quality of information provided. Surgeon websites should explicitly state the surgeons' beliefs concerning potentially controversial topics such as MIS and CAOS TKA in order to prevent patient misinterpretation.

A number of potential advantages including less blood loss, less pain, quicker recovery, quicker return to daily activities, and better alignment persuade some surgeons to advocate MIS and CAOS TKA. Although achieving these benefits by utilizing smaller incisions with less soft tissue dissection is a sensible goal, the increased difficulty and broadened learning curve3,21 associated with such a procedure should be considered when presenting this option to a patient or promoting via the Internet. There have been recent reports in the literature suggesting an inverse relationship between surgeon volume and surgical complication rates in total joint arthroplasty.9,11,20 The added difficulty and broadened learning curve associated with novel TKA procedures are likely to introduce further complication. Without further study, the benefit of MIS and CAOS surgery performed by low volume joint replacement surgeons remains questionable. Additionally, because MIS and CAOS TKA are relatively novel procedures most reported results are from short-term studies.

Advertising technology without sufficient scientific support not only misinforms the patient, but also produces indirect economic and social pressure on the orthopaedic surgeon to perform novel and unproven procedures. While decreased recovery time and less short-term pain may make MIS TKA an easy sell to the patient, the real goal of TKA is years of pain relief and unfettered ambulation. While short-term studies may be promising, it is important to maintain discretion when promoting MIS and CAOS TKA until long-term studies document these novel techniques are as efficacious as traditional surgery.

Although MIS and CAOS TKA were frequently discussed, only a small percentage of Knee Society members (10.9%) directly promoted or made claims about the techniques. Minimally invasive and CAOS TKA information was more often indirectly associated with Knee Society surgeons through institutional websites or hospital affiliations (21.7%, 20 of 92). While MIS and CAOS TKA were not often directly promoted via the Internet by members of the Knee Society, it is important to understand that from a potential patient's perspective, MIS and CAOS information indirectly associated with a surgeon may be mistaken as endorsing the procedure especially if there is no clear statement of the surgeon's beliefs.

Our survey of Knee Society members represents a small population of surgeons performing TKAs. This cohort was chosen because information provided by Knee Society members is representative of accurate information on MIS TKA. It is possible the extent of Internet advertisements by a larger cohort of surgeons performing TKA at a lower annual volume would occur on a larger scale.

References

1. Alan RK, Tria AJ Jr. Quadriceps-sparing total knee arthroplasty using the posterior stabilized TKA design. J Knee Surg. 2006;19: 71-76.
2. Bhattacharyya T, Tornetta P 3rd, Healy WL, Einhorn TA. The validity of claims made in orthopaedic print advertisements. J Bone Joint Surg Am. 2003;85:1224-1228.
3. Bonutti PM, Mont MA, McMahon M, Ragland PS, Kester M. Minimally invasive total knee arthroplasty. J Bone Joint Surg Am. 2004; 86:26-32.
4. Bozic KJ, Saleh KJ, Rosenberg AG, Rubash HE. Economic evaluation in total hip arthroplasty: analysis and review of the literature. J Arthroplasty. 2004;19:180-189.
5. Callaghan JJ, O'Rourke MR, Iossi MF, Liu SS, Goetz DD, Vittetoe DA, Sullivan PM, Johnston RC. Cemented rotating-platform total knee replacement. A concise follow-up, at a minimum of fifteen years, of a previous report. J Bone Joint Surg Am. 2005;87: 1995-1998.
6. Dalury DR, Dennis DA. Mini-incision total knee arthroplasty can increase risk of component malalignment. Clin Orthop Relat Res. 2005;440:77-81.
7. Decking R, Markmann Y, Fuchs J, Puhl W, Scharf HP. Leg axis after computer-navigated total knee arthroplasty: a prospective randomized trial comparing computer-navigated and manual implantation. J Arthroplasty. 2005;20:282-288.
8. Gill GS, Joshi AB. Long-term results of Kinematic Condylar knee replacement: an analysis of 404 knees. J Bone Joint Surg Br. 2001; 83:355-358.
9. Hervey SL, Purves HR, Guller U, Toth AP, Vail TP, Pietrobon R. Provider volume of total knee arhroplasties and patient outcomes in the HCUP-nationwide inpatient sample. J Bone Joint Surg Am. 2003;85:1775-1783.
10. Holt G, Wheelan K, Gregori A. The ethical implications of recent innovations in knee arthroplasty. J Bone Joint Surg Am. 2006;88: 226-229.
11. Katz JN, Losina E, Barrett J, Phillips CB, Mahomed NM, Lew RA, Guadagnoli E, Harris WH, Poss R, Baron JA. Association between hospital and surgeon procedure volume and outcomes of total hip replacement in the United States medicare population. J Bone Joint Surg Am. 2001;83:1622-1629.
12. Kim SJ, MacDonald M, Hernandez J. Wixson RL. Computer assisted navigation in total knee artrhoplasty: improved coronal alignment. J Arthroplasty. 2005;20(Suppl 3):123-131.
13. Klein GR, Parvizi J, Sharkey PF, Rothman RH, Hozack WJ. Minimally invasive total hip arthroplasty: internet claims made by members of the hip society. Clin Orthop Relat Res. 2005;441:68-70.
14. McGrory B, Callaghan J, Kraay M, Jacobs J, Robb W, Wasielewski R. Editorial: minimally invasive and small-incision joint replacement surgery: what surgeons should consider. Clin Orthop Relat Res. 2005;440:251-254.
15. Pavone V, Boettner F, Fickert S, Sculco TP. Total condylar knee arthroplasty: a long-term follow-up. Clin Orthop Relat Res. 2001; 388:18-25.
16. Reid JB 3rd, Guttmann D, Ayala M, Lubowitz JH. Minimally invasive surgery-total knee arthroplasty. Arthroscopy. 2004;20: 884-889.
17. Ritter MA, Berend ME, Meding JB, Keating EM, Faris PM, Crites BM. Long-term follow-up of anatomic graduated components posterior cruciate-retaining total knee replacement. Clin Orthop Relat Res. 2001;388:51-57.
18. Robinson M, Eckhoff DG, Reinig KD, Bagur MM, Bach JM. Variability of landmark identification in total knee arthroplasty. Clin Orthop Relat Res. 2006;442:57-62.
19. Rodgriguez JA, Bhende H, Ranawat CS. Total condylar knee replacement: a 20-year followup study. Clin Orthop Relat Res. 2001; 388:10-17.
20. Soohoo NF, Zingmond DS, Lieberman JR, Ko CY. Primary total knee artrhoplasty in California 1991 to 2001: does hospital volume affect outcomes? J Arthroplasty. 2006;21:199-205.
21. Tria AJ Jr. Minimally invasive total knee arthroplasty: the importance of instrumentation. Orthop Clin North Am. 2004;35:227-234.
22. Tria AJ Jr, Coon TM. Minimal incision total knee arthroplasty: early experience. Clin Orthop Relat Res. 2003;416:185-190.
23. Vail TP. Minimally invasive knee arthroplasty. Clin Orthop Relat Res. 2004;428:51-52.
24. Van Damme G, Defoort K, Ducoulombier Y, Van Glabbeek F, Bellemans J, Victor J. What should the surgeon aim for when performing computer-assisted total knee arthroplasty? J Bone Joint Surg Am. 2005;87(Suppl 2):52-58.
25. Yau WP, Leung A, Chiu KY, Tang WM, Ng TP. Intraobserver errors in obtaining visually selected anatomic landmarks during registration process in nonimage- based navigation-assisted total knee arthroplasty: a cadaveric experiment. J Arthroplasty. 2005;20: 591-601.

APPENDIX 1.

Data Collection Questionnaire (modified from Klein et al13)

Minimally Invasive TKA Internet Claims made by Active Knee Society Physicians Questionnaire

Surgeon Name:

Web site address 1:

Web site address 2:

Number of Knee Society members sharing website:

Type of website:

  1. University
  2. Hospital/HMO
  3. Private Practice/Clinic
  4. Surgeon Specific
  5. Research/Company
  • 1) Does Primary Site contain a direct link to:
    1. AAOS
    2. Knee Society
    3. Industry Site (ie, Stryker, DePuy, etc)
  • 2) Is minimally invasive surgery related to Orthopaedics but unrelated to TKA or UNI-knee replacement mentioned? (ie, Arthroscopy, Spine, Hip, etc)

If MIS Information related to TKA or UNI is provided:

  • 3) Provide web address w/Affiliation (ie, University, Company, etc)
    1. Direct + Affiliation
    2. Indirect + Affiliation
  • 4) Is procedure referred to as “Minimally/Less Invasive” Surgery w/r/t TKA or UNI-knee replacement?
    1. Y/N
    2. If yes, are initials MIS used
  • 5) Is procedure referred to as “Minimal/Mini/Micro Incision” Surgery w/r/t TKA or UNI-knee replacement?
    1. Y/N
    2. If yes, are initials MIS used
  • 6) Which procedure is mentioned w/r/t MIS?
    1. TKA
    2. UNI
    3. Both TKA and UNI
  • 7) Are risks of the MIS procedure presented/referred to (Y/N)?
  • 8) Does the website claim a smaller incision associated with the MIS procedure?
    1. Y/N
    2. Is the incision size given? (N/size)
  • 9) Does the website claim less invasiveness/tissue trauma associated with the MIS procedure?
    1. Y/N
    2. Supporting Data
      1. None
      2. Unpublished data
      3. Published data (peer review?)
  • 10) Does the website claim a greater/more natural range of motion associated with the MIS procedure?
    1. Y/N
    2. Supporting data for statement
      1. None
      2. Unpublished data
      3. Published data (peer review?)
  • 11) Does the website claim less blood loss resulting from the MIS procedure? a. Y/N b. Supporting data for statement
    1. Y/N
    2. Supporting data for statement
      1. None
      2. Unpublished data
      3. Published data (peer review?)
  • 12) Does the website claim less pain associated with the MIS procedure?
    1. Y/N
    2. Supporting Data
      1. None
      2. Unpublished data
      3. Published data (peer review?)
  • 13) Does the website claim a faster recovery associated with the MIS procedure?
    1. Y/N
    2. Supporting Data
      1. None
      2. Unpublished data
      3. Published data (peer review?)
  • 14) Does the website claim a shorter surgery time associated with the MIS procedure?
    1. Y/N
    2. Supporting data for statement
      1. None
      2. Unpublished data
      3. Published data (peer review?)
  • 15) Does the website claim the MIS procedure is safer/has fewer complications?
    1. Y/N
    2. Supporting data for statement
      1. None
      2. Unpublished data
      3. Published data (peer review?)
  • 16) Does the website claim a shorter hospital stay associated with the MIS procedure?
    1. Y/N
    2. Supporting data
      1. None
      2. Unpublished data
      3. Published data (peer review?)
  • 17) Does the website claim a need for less medication following the MIS procedure?
    1. Y/N
    2. Supporting data
      1. None
      2. Unpublished data
      3. Published data (peer review?)
  • 18) Does the website refer to the MIS procedure as quad sparing?
    1. Y/N
    2. Supporting data
      1. None
      2. Unpublished data
      3. Published data (peer review?)
  • 19) Does the website refer to the procedure as muscle sparing?
    1. Y/N
    2. Supporting data
      1. None
      2. Unpublished data
      3. Published data (peer review?)
  • 20) Does the website suggest a faster return to work/function?
    1. Y/N
    2. Supporting data
      1. None
      2. Unpublished data
      3. Published data (peer review?)
  • 21) Is computer assistance referred to w/r/t MIS?
    1. Y/N
    2. CAOS (Y/N)
    3. CAS (Y/N)
    4. More Accurate? (Y/N)
© 2006 Lippincott Williams & Wilkins, Inc.