Observational Study
Copyright ©The Author(s) 2024. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Orthop. May 18, 2024; 15(5): 444-456
Published online May 18, 2024. doi: 10.5312/wjo.v15.i5.444
Unicompartmental knee arthroplasty vs high tibial osteotomy for knee osteoarthritis: A comparison of clinical and radiological outcomes
Frederick William Wyatt, Oday Al-Dadah
Frederick William Wyatt, Oday Al-Dadah, Translational and Clinical Research Institute, Faculty of Medical Sciences, Newcastle University, Newcastle Upon Tyne NE2 4HH, United Kingdom
Frederick William Wyatt, Oday Al-Dadah, Department of Trauma and Orthopaedic Surgery, South Tyneside District Hospital, South Shields NE34 0PL, United Kingdom
Author contributions: Wyatt FW was responsible for the writing of the final manuscript and also contributed towards study design, data acquisition and interpretation of the analysed data; Al-Dadah O contributed towards study design, data acquisition, data analysis and reviewed/edited the final written manuscript; and both authors have read and approved the final manuscript.
Institutional review board statement: This was an observational study using existing data from routine clinical care, therefore IRB approval was not required.
Informed consent statement: This was an observational study using existing data from routine clinical care, therefore separate consent forms were not required.
Conflict-of-interest statement: All the authors report no relevant conflicts of interest for this article.
Data sharing statement: Technical appendix, statistical code, and dataset available from the corresponding author at frederick.wyatt2@northumbria-healthcare.nhs.uk.
STROBE statement: The authors have read the STROBE Statement—checklist of items, and the manuscript was prepared and revised according to the STROBE Statement—checklist of items.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: https://creativecommons.org/licenses/by-nc/4.0/
Corresponding author: Frederick William Wyatt, MBBS, MRes, Academic Foundation Doctor, Translational and Clinical Research Institute, Faculty of Medical Sciences, Newcastle University, Framlington Place, Newcastle Upon Tyne NE2 4HH, United Kingdom. frederick.wyatt2@northumbria-healthcare.nhs.uk
Received: January 23, 2024
Revised: March 5, 2024
Accepted: April 12, 2024
Published online: May 18, 2024
Abstract
BACKGROUND

Unicompartmental knee arthroplasty (UKA) and high tibial osteotomy (HTO) are well-established operative interventions in the treatment of knee osteoarthritis. However, which intervention is more beneficial to patients with knee osteoarthritis remains unknown and a topic of much debate. Simultaneously, there is a paucity of research assessing the relationship between radiographic parameters of knee joint alignment and patient-reported clinical outcomes, preoperatively and following HTO or UKA.

AIM

To compare UKAs and HTOs as interventions for medial-compartment knee osteoarthritis: Examining differences in clinical outcome and investigating the relationship of joint alignment with respect to this.

METHODS

This longitudinal observational study assessed a total of 42 patients that had undergone UKA (n = 23) and HTO (n = 19) to treat medial compartment knee osteoarthritis. Patient-reported outcome measures (PROMs) were collected to evaluate clinical outcome. These included two disease-specific (Knee Injury and Osteoarthritis Outcome Score, Oxford Knee Score) and two generic (EQ-5D-5L, Short Form-12) PROMs. The radiographic parameters of knee alignment assessed were the: Hip-knee-ankle angle, mechanical axis deviation and angle of Mikulicz line.

RESULTS

Statistical analyses demonstrated significant (P < 0.001), preoperative to postoperative, improvements in the PROM scores of both groups. There were, however, no significant inter-group differences in the postoperative PROM scores of the UKA and HTO group. Several significant correlations associated a more distolaterally angled Mikulicz line with worse knee function and overall health preoperatively (P < 0.05). Postoperatively, two clusters of significant correlations were observed between the disease-specific PROM scores and knee joint alignment parameters (hip-knee-ankle angle, mechanical axis deviation) within the HTO group; yet no such associations were observed within the UKA group.

CONCLUSION

UKAs and HTOs are both efficacious operations that provide a comparable degree of clinical benefit to patients with medial compartment knee osteoarthritis. Clinical outcome has a limited association with radiographic parameters of knee joint alignment postoperatively; however, a more distolaterally angled Mikulicz line appears associated with worse knee function/health-related quality of life preoperatively.

Keywords: Arthroplasty, Osteotomy, Medial compartment, Osteoarthritis, Knee alignment, Patient reported outcome measures

Core Tip: A great deal of uncertainty exists in the literature about which operation, out of unicompartmental knee arthroplasty (UKA) or high tibial osteotomy (HTO), is more beneficial in the treatment of knee osteoarthritis. This study adds evidence to the existing literature base, concluding that HTOs and UKAs are equally efficacious operative interventions capable of providing a comparable degree of improvement in joint function and global health-related quality of life, to those with medial compartment knee osteoarthritis at one year postoperatively. This study is the first of its kind to report a correlation analysis between the angle of Mikulicz line and patient-reported health outcomes. It demonstrated that preoperatively, a more distolaterally angled Mikulicz line was associated worse knee function/health-related quality of life. The mechanisms underlying this relationship remain unknown and represent an avenue for future research; the authors of this study posit an association with the external knee adduction moment.