Skip to main content
SpringerLink
Log in

A New High-flexion Knee Scoring System to Eliminate the Ceiling Effect

  • Clinical Research
  • Published:
Clinical Orthopaedics and Related Research®

Abstract

Background

Various scoring systems document improvement after TKA, but most are associated with a ceiling effect that may fail to distinguish between patients having different levels of knee function after TKA. We therefore developed a new scoring system for patients with higher levels of flexion to eliminate ceiling effects observed with current systems.

Questions/purposes

The purposes of this study were (1) to determine whether the high-flexion knee score eliminates the ceiling effect, (2) to assess the validity and responsiveness of the high-flexion knee score, and (3) to determine whether the high-flexion knee score can aid in differentiation of the knee status of patients at the ceiling level.

Methods

We prospectively studied 165 patients with 201 well-functioning knees who had undergone primary TKA. We obtained Knee Society scores, WOMAC scores, Feller scores, SF-36 scores, and high-flexion knee scores for all patients. The high-flexion knee score includes items that reflect knee function in the high functional range, such as sitting on or rising from the floor, squatting, or kneeling. We determined the ceiling effects and score distributions of various scoring systems. We performed a convergent validity test of the high-flexion knee score by correlation analysis with these various scoring systems. Responsiveness of the high-flexion knee score was assessed by correlation analysis of changes in various scoring systems. To determine whether the high-flexion knee score can aid in differentiation of knee status of patients at the ceiling level, relative responsiveness of the various scores in the ceiling versus below the ceiling range was determined.

Results

The high-flexion knee score showed no ceiling effect, whereas the other systems did. Addition of the high-flexion knee score to the other scoring systems eliminated these ceiling effects and resulted in more normalized score distributions. The high-flexion knee score correlated (r = −0.77) with WOMAC in postoperative scores, and it also correlated with the changes in WOMAC (r = −0.69) and SF-36 physical functioning (r = 0.62). The correlation of WOMAC score with SF-36 physical function score was lower in patients at the ceiling level of the Knee Society knee score and Knee Society function score, compared with the correlation at below-ceiling range, whereas the high-flexion knee score maintained a correlation with the SF-36 physical function score, even at the ceiling level of the Knee Society knee score and Knee Society function score.

Conclusions

Compared with other systems, the high-function knee score appears valid for evaluating the knee status in the high-flexion range. Our data suggest the high-flexion knee score differentiates among the knee status in the high-function range. Furthermore, the high-function knee score eliminates the ceiling effect of the currently used scoring tools, and thus may be useful when combined with other scoring systems.

Level of Evidence

Level III, diagnostic study. See Guidelines for Authors for a complete description of levels of evidence.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Fig. 1A–E
Fig. 2A–D
Fig. 3A–E

Similar content being viewed by others

References

  1. Anderson JG, Wixson RL, Tsai D, Stulberg SD, Chang RW. Functional outcome and patient satisfaction in total knee patients over the age of 75. J Arthroplasty. 1996;11:831–840.

    Article  PubMed  CAS  Google Scholar 

  2. Bellamy N, Buchanan WW, Goldsmith CH, Campbell J, Stitt LW. Validation study of WOMAC: a health status instrument for measuring clinically important patient relevant outcomes to antirheumatic drug therapy in patients with osteoarthritis of the hip or knee. J Rheumatol. 1988;15:1833–1840.

    PubMed  CAS  Google Scholar 

  3. Bourne RB. Measuring tools for functional outcomes in total knee arthroplasty. Clin Orthop Relat Res. 2008;466:2634–2638.

    Article  PubMed  Google Scholar 

  4. Clayton RA, Amin AK, Gaston MS, Brenkel IJ. Five-year results of the Sigma total knee arthroplasty. Knee. 2006;13:359–364.

    Article  PubMed  Google Scholar 

  5. Corzillius M, Fortin P, Stucki G. Responsiveness and sensitivity to change of SLE disease activity measures. Lupus. 1999;8:655–659.

    Article  PubMed  CAS  Google Scholar 

  6. Cushnaghan J, Bennett J, Reading I, Croft P, Byng P, Cox K, Dieppe P, Coggon D, Cooper C. Long-term outcome following total knee arthroplasty: a controlled longitudinal study. Ann Rheum Dis. 2009;68:642–647.

    Article  PubMed  CAS  Google Scholar 

  7. Ethgen O, Bruyere O, Richy F, Dardennes C, Reginster JY. Health-related quality of life in total hip and total knee arthroplasty: a qualitative and systematic review of the literature. J Bone Joint Surg Am. 2004;86:963–974.

    PubMed  Google Scholar 

  8. Feller JA, Bartlett RJ, Lang DM. Patellar resurfacing versus retention in total knee arthroplasty. J Bone Joint Surg Br. 1996;78:226–228.

    PubMed  CAS  Google Scholar 

  9. Huang HT, Su JY, Wang GJ. The early results of high-flex total knee arthroplasty: a minimum of 2 years of follow-up. J Arthroplasty. 2005;20:674–679.

    Article  PubMed  Google Scholar 

  10. Huddleston JI, Scarborough DM, Goldvasser D, Freiberg AA, Malchau H. 2009 Marshall Urist Young Investigator Award: How often do patients with high-flex total knee arthroplasty use high flexion? Clin Orthop Relat Res. 2009;467:1898–1906.

    Article  PubMed  Google Scholar 

  11. Husted JA, Cook RJ, Farewell VT, Gladman DD. Methods for assessing responsiveness: a critical review and recommendations. J Clin Epidemiol. 2000;53:459–468.

    Article  PubMed  CAS  Google Scholar 

  12. Insall JN, Dorr LD, Scott RD, Scott WN. Rationale of the Knee Society clinical rating system. Clin Orthop Relat Res. 1989;248:13–14.

    PubMed  Google Scholar 

  13. Jorn LP, Johnsson R, Toksvig-Larsen S. Patient satisfaction, function and return to work after knee arthroplasty. Acta Orthop Scand. 1999;70:343–347.

    Article  PubMed  CAS  Google Scholar 

  14. Kane RL, Maciejewski M, Finch M. The relationship of patient satisfaction with care and clinical outcomes. Med Care. 1997;35:714–730.

    Article  PubMed  CAS  Google Scholar 

  15. Kim TH, Lee DH, Bin SI. The NexGen LPS-flex to the knee prosthesis at a minimum of three years. J Bone Joint Surg Br. 2008;90:1304–1310.

    Article  PubMed  Google Scholar 

  16. Lieberman JR, Dorey F, Shekelle P, Schumacher L, Thomas BJ, Kilgus DJ, Finerman GA. Differences between patients’ and physicians’ evaluations of outcome after total hip arthroplasty. J Bone Joint Surg Am. 1996;78:835–838.

    PubMed  CAS  Google Scholar 

  17. Lingard EA, Katz JN, Wright RJ, Wright EA, Sledge CB; Kinemax Outcomes Group. Validity and responsiveness of the Knee Society Clinical Rating System in comparison with the SF-36 and WOMAC. J Bone Joint Surg Am. 2001;83:1856–1864.

    PubMed  Google Scholar 

  18. Loughead JM, Malhan K, Mitchell SY, Pinder IM, McCaskie AW, Deehan DJ, Lingard EA. Outcome following knee arthroplasty beyond 15 years. Knee. 2008;15:85–90.

    Article  PubMed  CAS  Google Scholar 

  19. McHorney CA, Ware JE Jr, Raczek AE. The MOS 36-Item Short-Form Health Survey (SF-36): II. Psychometric and clinical tests of validity in measuring physical and mental health constructs. Med Care. 1993;31:247–263.

    Article  PubMed  CAS  Google Scholar 

  20. Moretti C, Viola S, Pistorio A, Magni-Manzoni S, Ruperto N, Martini A, Ravelli A. Relative responsiveness of condition specific and generic health status measures in juvenile idiopathic arthritis. Ann Rheum Dis. 2005;64:257–261.

    Article  PubMed  CAS  Google Scholar 

  21. Noble PC, Conditt MA, Cook KF, Mathis KB. The John Insall Award: Patient expectations affect satisfaction with total knee arthroplasty. Clin Orthop Relat Res. 2006;452:35–43.

    Article  PubMed  Google Scholar 

  22. Rationale of The Knee Society Clinical Rating System. Available at: http://www.kneesociety.org/web/outcomes.html. Accessed September 23, 2011.

  23. Schai PA, Thornhill TS, Scott RD. Total knee arthroplasty with the PFC system. Results at a minimum of ten years and survivorship analysis. J Bone Joint Surg Br. 1998;80:850–858.

    Article  PubMed  CAS  Google Scholar 

  24. Shah AK, Celestin J, Parks ML, Levy RN. Long-term results of total joint arthroplasty in elderly patients who are frail. Clin Orthop Relat Res. 2004;425:106–109.

    Article  PubMed  Google Scholar 

  25. Stucki G, Liang MH, Fossel AH, Katz JN. Relative responsiveness of condition-specific and generic health status measures in degenerative lumbar spinal stenosis. J Clin Epidemiol. 1995;48:1369–1378.

    Article  PubMed  CAS  Google Scholar 

  26. Tegner Y, Lysholm J. Rating systems in the evaluation of knee ligament injuries. Clin Orthop Relat Res. 1985;198:43–49.

    PubMed  Google Scholar 

  27. Terwee CB, Bot SD, de Boer MR, van der Windt DA, Knol DL, Dekker J, Bouter LM, de Vet HC. Quality criteria were proposed for measurement properties of health status questionnaires. J Clin Epidemiol. 2007;60:34–42.

    Article  PubMed  Google Scholar 

  28. Whiteside LA, Arima J. The anteroposterior axis for femoral rotational alignment in valgus total knee arthroplasty. Clin Orthop Relat Res. 1995;321:168–172.

    PubMed  Google Scholar 

  29. Wright J, Ewald FC, Walker PS, Thomas WH, Poss R, Sledge CB. Total knee arthroplasty with the kinematic prosthesis. Results after five to nine years: a follow-up note. J Bone Joint Surg Am. 1990;72:1003–1009.

    PubMed  CAS  Google Scholar 

  30. Wright JG, Young NL. A comparison of different indices of responsiveness. J Clin Epidemiol. 1997;50:239–246.

    Article  PubMed  CAS  Google Scholar 

Download references

Acknowledgments

We thank Seonwoo Kim PhD and Minji Kim MS for support with statistical analysis and Tai-Hee Seo BS for efforts in collecting the raw data for this study.

Author information

Authors and Affiliations

  1. Department of Orthopedic Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50 Irwon-dong, Gangnam-gu, Seoul, 135-710, Republic of Korea

    Sang-Eun Na MD, Chul-Won Ha MD & Choong-Hee Lee MD

Authors
  1. Sang-Eun Na MD
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Chul-Won Ha MD
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Choong-Hee Lee MD
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to Chul-Won Ha MD.

Additional information

Each author certifies that he has no commercial associations (eg, consultancies, stock ownership, equity interest, patent/licensing arrangements, etc) that might pose a conflict of interest in connection with the submitted article.

Each author certifies that his institution approved the human protocol for this investigation, that all investigations were conducted in conformity with ethical principles of research.

Electronic supplementary material

Below is the link to the electronic supplementary material.

Supplementary material 1 (DOCX 17 kb)

About this article

Cite this article

Na, SE., Ha, CW. & Lee, CH. A New High-flexion Knee Scoring System to Eliminate the Ceiling Effect. Clin Orthop Relat Res 470, 584–593 (2012). https://doi.org/10.1007/s11999-011-2203-5

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s11999-011-2203-5

Keywords

Search

Navigation