International Orthopaedics

, Volume 43, Issue 12, pp 2739–2745 | Cite as

The forgotten joint score in total and unicompartmental knee arthroplasty: a prospective cohort study

  • Geert PeersmanEmail author
  • Jeroen Verhaegen
  • Barbara Favier
Original Paper



The purpose of this study was to assess whether unicompartmental knee arthroplasty (UKA) results in better patient-reported and clinical outcome than total knee arthroplasty (TKA). The study hypothesis was UKA yields better patient-reported and clinical outcomes than TKA.


Our prospective cohort study compared patients who underwent medial UKA or TKA from February 2014 through June 2015. Forgotten Joint Score (FJS), the short form of the Knee Injury and Osteoarthritis Outcome Score (KOOS PS), EuroQOL Five Dimensions Questionnaire (EQ-5D), and the Knee Society Score (KSS) were completed at two weeks, six weeks, three months, six months, and one year post-operatively. The KOOS PS, EQ-5D, and the KSS were also documented pre-operatively.


Fifty-seven patients (57 knees) were allocated to the UKA group and 62 patients (62 knees) to the TKA group. At baseline, no statistically significant differences were observed between groups regarding patient demographics and pre-operative scores. Except for FJS at 2 weeks (p = 0.326), all postoperative scores revealed significant differences as early as two weeks and up to 12 months (p < 0.05).


Our findings suggest UKA patients are less aware of their joint replacements than TKA patients for medial osteoarthritis of the knee. UKA conserves more soft tissue and bone than TKA, which may be the reason for the differences observed.


Cohort study Forgotten joint score Osteoarthritis Knee Patient-reported outcome Total knee arthroplasty Unicompartmental knee arthroplasty 


Compliance with ethical standards

Conflict of interest

GP is a Consultant for Zimmer Biomet. The other authors have no conflicts of interest.


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Copyright information

© SICOT aisbl 2019

Authors and Affiliations

  • Geert Peersman
    • 1
    • 2
    Email author
  • Jeroen Verhaegen
    • 1
  • Barbara Favier
    • 1
  1. 1.Department of Orthopaedic SurgeryZiekenhuis Netwerk AntwerpenAntwerpBelgium
  2. 2.Institute for Orthopaedic Research and TrainingKU Leuven / UZ LeuvenLeuvenBelgium

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