Midterm Results of Cementless and Cemented Unicondylar Knee Arthroplasty with Mobile Meniscal Bearing: A Prospective Cohort Study

Radosław Stempin1, *, Wiesław Kaczmarek1, Kacper Stempin2, Julian Dutka3
1 Department of Orthopedic Surgery Promienista Clinic, Poznan, Poland
2 Department of Orthopedic & Trauma Surgery Westallgäu Clinic, Wangen, Germany
3 Department of Orthopedic& Trauma Surgery S. Zeromski Memorial Hospital Cracow, Poland

Article Metrics

CrossRef Citations:
Total Statistics:

Full-Text HTML Views: 1079
Abstract HTML Views: 483
PDF Downloads: 290
ePub Downloads: 246
Total Views/Downloads: 2098
Unique Statistics:

Full-Text HTML Views: 625
Abstract HTML Views: 330
PDF Downloads: 209
ePub Downloads: 200
Total Views/Downloads: 1364

Creative Commons License
© 2017 Stempin et al.

open-access license: This is an open access article distributed under the terms of the Creative Commons Attribution 4.0 International Public License (CC-BY 4.0), a copy of which is available at: This license permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

* Address correspondence to this author at the Department of Orthopedic Surgery Promienista Clinic, Poznan, Poland, Tel: + 48 601 727 982; Email:



Cemented unicompartmental knee arthroplasty (UKA) yields good clinical outcome but common revision reasons are loosening and pain. Cementless UKA may reduce the revision rate.


The current study was designed to assess clinical and radiographic outcome of cemented and cementless UKA, using bone quality as determined by the Bone Hardness Test (BHT) as selection criterion for cementless implantation.


In this prospective comparative cohort study we analyzed 50 cementless and 29 Oxford consecutive UKA cases. Patients with sufficient bone quality were eligible for cementless UKA. Bone quality was assessed with the BHT, which consisted of exercising pressure with the thumb on the bone surface created after resection of the tibia.


The average surgical times were 62.5 ± 12.6 and 78 ± 16 minutes in the cementless and the cemented group, respectively (p < 0.01). The average thickness of the polyethylene insert was 4.3 ± 1.2 (range, 3 – 9) and 3.7 ± 0.8 (range, 3 – 6) mm, respectively (p = 0.02). Both types of implants yielded excellent clinical and functional results. At an average follow-up time of seven years, we found non-significant differences between clinical results of cementless versus cemented implants.


Shorter surgical time makes cementless implantation more attractive to surgeons when considering UKA options for their patients. The average thickness of the polyethylene insert in cementless group was 0.6 mm thinner than in the cemented group. The BHT is a simple and useful test to assess whether patients are eligible for cementless UKA.

Keywords: Osteoarthritis, knee, Unicompartmental knee arthroplasty, Mobile meniscal bearing, Cohort study, Implant fixation, Clinical outcome, Bone hardness test.