Cruciate-Retaining Total Knee Arthroplasty versus Unicompartmental Knee Arthroplasty in Medial Compartmental Osteoarthritis: A Propensity Score-Matched Analysis of Early Postoperative Recovery

Abstract

Background

Cruciate-retaining (CR) total knee arthroplasty (TKA) may provide better physiological knee kinematics, proprioception, and quadricep recovery than posterior-stabilized (PS) TKA. Therefore, we hypothesized that CR TKA with multimodal pain control may provide comparable postoperative pain and recovery as unicompartmental knee arthroplasty (UKA).

Methods

This study included patients with isolated medial compartment knee osteoarthritis who underwent CR TKA and UKA. TKA and UKA patients were propensity score-matched with age and body mass index (BMI) and compared using visual analog scales (VAS) for pain scores, total amount of morphine use (TMU), knee flexion angle, straight leg raise (SLR), independent ambulation, length of hospital stay (LOS), and costs during hospitalization.

Results

After propensity score matching, 46 patients were included in the TKA and UKA groups, respectively, with no differences in demographic data. VAS at 6–72 h and TMU at 48 h after surgery were comparable between the groups. The knee flexion angle in the UKA group was significantly higher at 24 h (60.0° vs 46.6°; p<0.001) and 48 h (76.9° vs 69.1°; p = 0.021) than that in the TKA group. The SLR in the UKA group was significantly higher than that in the TKA group at 24–72 h. The UKA group ambulated significantly earlier (1.56 vs 2.13 days; p<0.001), had shorter LOS (3.68 vs 4.28 days; p<0.004) and incurred 12.43% lower costs when compared to the TKA group.

Conclusion

Patients who underwent CR TKA with multimodal pain management did not experience more postoperative pain or morphine use than those who underwent UKA. However, UKA patients seem to experienced faster recovery and shorter LOS than CR-TKA patients during the early postoperative course. Accordingly, UKA may be considered instead of TKA for patients who are good candidates for UKA and require expedited recovery.

Keywords:

• total knee arthroplasty
• cruciate-retaining
• unicompartmental knee arthroplasty
• postoperative pain
• recovery

Ethics Approval and Informed Consent

Ethical clearance was obtained from the Institutional Review Board of the Naresuan University (IRB number P3-0015/2563 with protocol number 112/2020). Participants for the research will be selected based on predefined criteria. Before collecting the data, describe the details regarding the research data, explaining how the data collected in this research will be used for research purposes, and provide details about the research itself. Those who are selected to participate in the research must agree to participate and sign personally. The study was carried out in compliance with the International guidelines for human research protection as Declaration of Helsinki, The Belmont Report, CIOMS guideline and International Conference on Harmonization in Good Clinical Practice (ICH-GCP).

Acknowledgments

The authors gratefully acknowledge Bhuwad Chinwatanawongwan, MD; Pawin Sudbanthad, MD; Sasawat Ratanapises, MD; Passakorn Teekaweerakit, MD; Parin Samapath, MD; and Wasee Lertkajornsin for their technical assistance; and Ms. Dollapas Punpanich for her expertise with statistical analysis. We thank Mr. Roy I. Morien of the Naresuan University Graduate School for his assistance in editing the English expression and grammar in this document.

Disclosure

The authors report no conflicts of interest in this work.

Additional information

Funding

This study was performed with no external funding.