Noise after total knee arthroplasty has limited effect on joint awareness and patient-reported clinical outcomes: retrospective study

BMC Musculoskelet Disord. 2020 Feb 21;21(1):115. doi: 10.1186/s12891-020-3134-7.


Background: Some patients complain of noise after total knee arthroplasty (TKA). Controversy still exists on how the noise affects the clinical outcomes, including joint awareness, after TKA. The Forgotten Joint Score-12 (FJS-12) measures the clinical outcomes focusing on joint awareness after surgery. The Knee Society Scoring System-2011 (KSS-2011) includes questionnaires for satisfaction, expectation, and functional activities. The aim of this study is to clarify the relationship among FJS-12, KSS-2011, and the noise. Furthermore, the relationship between FJS-12 and KSS-2011 was validated.

Methods: Using FJS-12 and KSS-2011, 295 knees from 225 patients who underwent TKA were retrospectively evaluated. Noise perception was evaluated by a questionnaire with five grades, a method that follows the questionnaire form of FJS-12 ("Are you aware of the noise of your artificial joint?"; never, almost never, seldom, sometimes, mostly). Correlations among FJS-12, KSS-2011, and noise were analyzed. The patients were divided into four groups based on the mechanism of their implant [cruciate retaining, posterior stabilized, cruciate sacrificed, and bicruciate stabilized (BCS)]. FJS-12, KSS-2011, and noise were compared among the groups.

Results: A strong correlation was found between FJS-12 and total score of KSS-2011 (0.70; P < 0.001). FJS-12 correlated with KSS-2011 subcategories of "symptoms," "satisfaction," and "standard activities," with correlation coefficients at approximately 0.60. Noise had weak correlations with FJS-12 (0.28; P < 0.001) and KSS-2011 (0.20 P < 0.001). In comparing the TKA mechanisms, BCS had remarkably better KSS-2011 and greater movement range but worse noise scores.

Conclusions: Noise perception after TKA had limited effect on joint awareness and clinical outcomes. FJS-12 correlated strongly with KSS-2011 and associated with satisfaction, residual symptoms, and daily activities, as assessed by KSS-2011 subscores.

Trial registration: This study was approved by the Medical Ethical Committee of the Tokyo Women's Medical University (approval number: 4681 on March 2, 2018).

Keywords: Joint awareness; Noises; Patient satisfaction; Patient-reported outcome measures; Total knee arthroplasty.

MeSH terms

  • Aged
  • Aged, 80 and over
  • Arthroplasty, Replacement, Knee / adverse effects
  • Arthroplasty, Replacement, Knee / trends*
  • Awareness*
  • Cross-Sectional Studies
  • Female
  • Humans
  • Knee Joint / surgery
  • Knee Prosthesis / adverse effects
  • Knee Prosthesis / trends*
  • Male
  • Middle Aged
  • Noise* / adverse effects
  • Patient Reported Outcome Measures*
  • Patient Satisfaction*
  • Retrospective Studies