Rapeepat Narkbunnam1, Karn Rojjananukulpong2, Pakpoom Ruangsomboon1, Keerati Chareancholvanich1, Chaturong Pornrattanamaneewong1

1Department of Orthopaedic Surgery, Division of Adult Reconstructive Surgery, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
2Department of Orthopaedic Surgery, Bamrasnaradura Infectious Diseases Institute, Bangkok, Thailand

Keywords: Floor activities patient perception, unicompartmental knee arthroplasty.


Objectives: This study aims to evaluate the association between patientsʼ perception and their ability to perform floor activities after mobile-bearing unicompartmental knee arthroplasty (MB-UKA).

Patients and methods: This prospective, cross-sectional study included a total of 63 knees of 63 patients (7 males, 56 females; mean age: 65.6±6.2 years; range, 51 to 79 years) with anteromedial osteoarthritis knee who had MB-UKA with a follow-up period of at least one year postoperatively. Each participant was asked to rate their perception of their ability to perform six floor activities. Their actual abilities were measured by using a five-category anchored scale. The primary outcome was the association between participants’ perception and their actual ability. The secondary outcome was to evaluate factors affecting patients’ actual ability.

Results: More than 60% of the patients could achieve good actual ability scores in performing chair kneeling, floor kneeling, and sitting side-legged regardless of their perception. Chair kneeling at 90 degrees had the most patients (69.8%) with good actual ability scores. Standing up from the floor was the activity with the highest positive perception rate of 84.1%. However, relatively lower actual activity scores were observed in floor squatting, cross-legged sitting, and standing up from the floor. Floor squatting yielded the lowest rate of positive perception and actual ability scores (39.1% and 20.6%, respectively). The Oxford Knee Score and knee flexion angle had moderate positive correlations with the actual ability scores (r=0.44 and 0.40, respectively).

Conclusion: Patients’ perception and their actual ability may differ for each floor activity after MB-UKA. An appropriate sequence of activities based on their difficulties along with positive reinforcement and appropriate patient education may yield favorable functional outcomes following MB-UKA.

Citation: Narkbunnam R, Rojjananukulpong K, Ruangsomboon P, Chareancholvanich K, Pornrattanamaneewong C. The association between perception of patients and their actual ability to do floor activities after mobile-bearing unicompartmental knee arthroplasty: A prospective, crosssectional study. Jt Dis Relat Surg 2023;34(2):245-252. doi: 10.52312/ jdrs.2023.877

Ethics Committee Approval

The study protocol was approved by the Siriraj Institutional Review Board Ethics Committee (date: 11.03.2016, no: 009/2559[EC4]). The study was conducted in accordance with the principles of the Declaration of Helsinki.

Author Contributions

Provided research questions, write manuscript and rebuttal: R.N.; Contribute to full manuscript development and rebuttal: P.R.; Conducted data collection, analyzed data and discussion and developed the draft manuscript: K.R.; Examined all data analysis, detailed the results, statistical calculation, monitored data and discussion: C.P.; Also provided useful advice and finalize the manuscript: K.C. All authors have read and approved the final submitted manuscript.

Conflict of Interest

The authors declared no conflicts of interest with respect to the authorship and/or publication of this article.

Financial Disclosure

This study was funded by faculty of Medicine, Siriraj Hospital, Mahidol University, Thailand (009/2559). The funding source had no influence on the interpretation of data, the final conclusion drawn, nor the decision to publish.


The authors acknowledge the assistance given by Nichakorn Khomawut with data collection. We thank Onlak Ruangsomboon for editing grammatical errors. We also acknowledge Suthipol Udompunthurak, MSc. (Applied Statistics), for his assistance with the statistical analyses.

Trial Registration

The study was approved by the Institutional review board of Siriraj Hospital, Mahidol University [SIRB 009/2559(EC4)].

Data Sharing Statement

The datasets generated and/or analyzed during the current study are not publicly available. These datasets were stored in our internal high-security level hard drive but are available from the corresponding author on reasonable request. Requests for data not shown in the body of this manuscript can be made to the corresponding author.