Original Article

A long-term cross-sectional study with modified forgotten joint score to assess the perception of artificial joint after total knee arthroplasty

¹ Resident in Orthopaedics, Amrita Institute of Medical Sciences, Kochi, 682041 Kerala, India
² Amrita Institute of Medical Sciences, Kochi, 682041 Kerala, India
³ Clinical Professor in Orthopaedics, Amrita Institute of Medical Sciences, Kochi, 682041 Kerala, India

^* Corresponding author: jaithilak@aims.amrita.edu

Received: 17 December 2020
Accepted: 21 February 2021

Abstract

Background and purpose: The ultimate goal for an arthroplasty surgeon is to provide the patient a joint that feels more like a natural joint. The Modified Forgotten Joint Score (MFJS) is a newly introduced functional scoring system that has a superior ability to assess this property among arthroplasty patients. The objective of this study is to evaluate the long-term temporal association of the MFJS and total knee arthroplasty (TKA). Methods: We assessed 360 patients post TKA with MFJS questionnaire. The patient groups were distributed at follow-up intervals of 3 weeks (n = 55), 6 months (n = 45), 1 year (n = 57), 2 years (n = 40), 3 years (n = 49), 5 years (n = 49), 7 years (n = 39), and 10 years (n = 26). Higher score suggests a forgotten artificial joint. Results: Post-operative mean MFJS scores were 64.4 ± 7.6 at 3 weeks, 87.7 ± 5.6 at 6 months, 89.2 ± 3.1 at 1 year, 89.9 ± 2.6 at 2 years, 89.4 ± 3.2 at 3 years, 89.1 ± 4 at 5 years, 84.5 ± 8.8 at 7 years, and 82.7 ± 11.9 at 10 years. The score at 3 weeks was significantly lesser than the average scores at other follow-up intervals. The score at 6 months was significantly higher compared to the score at 10 years. The average score at 1 year, 2 years, 3 years, and 5 years were significantly higher compared to the average score at 7 years and 10 years. Conclusion: The trend of the MFJS score was found to drastically improve from 3 weeks to 6 months and peak in 2 years after which the score tends to attain a plateau up to 5 years following which there is a decline in the score at 7- and 10-years post-surgery. Age did not have an influence on the variation in functional score in any of the follow-up groups. MFJS has a strong positive correlation with the well-recognised KOOS scoring system.

Level of evidence: IV