Abstract
Background
Balancing the relative advantages and disadvantages of unicompartmental knee arthroplasties (UKAs) against those for TKAs can be challenging. Survivorship is one important end point; arthroplasty registers repeatedly report inferior midterm survival rates, but longer-term data are sparse. Comparing survival directly by using arthroplasty register survival reports also may be inadequate because of differences in indications, implant designs, and patient demographics in patients having UKAs and TKAs.
Questions/purposes
The aims of this study were to assess the survivorship of UKA in the context of one large, northern European registry, and to compare the rates of survivorship with those of cemented TKAs performed for primary knee osteoarthritis during the same 27-year period.
Methods
From the Finnish Arthroplasty Register, we obtained the data for 4713 patients undergoing UKAs for primary osteoarthritis (mean age, 63.5 years; minimum followup, 0 years; mean, 6.0 years; range, 0–24 years) who had surgical revision between 1985 and 2011. From this cohort, we calculated the Kaplan-Meier survivorship for revision performed for any reason and compared it with the survivorship of 83,511 patients (mean age, 69.5 years; minimum followup 0 years; mean, 6.4 years; range, 0–27 years) with TKAs treated for primary osteoarthritis during the same period. Data were adjusted for age and sex in a comparative analysis.
Results
Kaplan-Meier survivorship of UKAs was 89.4% at 5 years, 80.6% at 10 years, and 69.6% at 15 years; the corresponding rates for TKAs were 96.3%, 93.3%, and 88.7%, respectively. UKAs had inferior long-term survivorship compared with cemented TKAs, even after adjusting for the age and sex of the patients (hazard ratio 2.2, p < 0.001).
Conclusions
A UKA offers tempting advantages compared with a TKA; however, the revision frequency for UKAs in widespread use, as measured in a large, national registry, was poorer than that of TKAs. When choosing between a UKA and a TKA, patients should be informed of advantages of both procedures, but they also should be advised about the generally higher revision risk after UKA.
Level of Evidence
Level III, therapeutic study. See the Instructions for Authors for a complete description of levels of evidence.
Similar content being viewed by others
References
Brown NM, Sheth NP, Davis K, Berend ME, Lombardi AV, Berend KR, Della Valle CJ. Total knee arthroplasty has higher postoperative morbidity than unicompartmental knee arthroplasty: a multicenter analysis. J Arthroplasty. 2012;27(8 suppl):86–90.
Dorey FJ. Survivorship analysis of surgical treatment of the hip in young patients. Clin Orthop Relat Res. 2004;418:23–28.
Epinette JA, Brunschweiler B, Mertl P, Mole D, Cazenave A; The French Society for the Hip and Knee. Unicompartmental knee arthroplasty modes of failure: wear is not the main reason for failure: a multicentre study of 418 failed knees. Orthop Traumatol Surg Res. 2012;98(suppl):S124–S130.
Eskelinen A, Remes V, Helenius I, Pulkkinen P, Nevalainen J, Paavolainen P. Uncemented total hip arthroplasty for primary osteoarthritis in young patients: a mid- to long-term follow-up study from the Finnish Arthroplasty Register. Acta Orthop. 2006;77:57–70.
Goodfellow JW, O’Connor JJ, Murray DW. A critique of revision rate as an outcome measure: re-interpretation of knee joint registry data. J Bone Joint Surg Br. 2010;92:1628–1631.
Gulati A, Chau R, Pandit HG, Gray H, Price AJ, Dodd CA, Murray DW. The incidence of physiological radiolucency following Oxford unicompartmental knee replacement and its relationship to outcome. J Bone Joint Surg Br. 2009;91:896–902.
Hamilton WG, Collier MB, Tarabee E, McAuley JP, Engh CA Jr, Engh GA. Incidence and reasons for reoperation after minimally invasive unicompartmental knee arthroplasty. J Arthroplasty. 2006;21(6 suppl 2):98–107.
Hopper GP, Leach WJ. Participation in sporting activities following knee replacement: total versus unicompartmental. Knee Surg Sports Traumatol Arthrosc. 2008;16:973–979.
Jahromi I, Walton NP, Dobson PJ, Lewis PL, Campbell DG. Patient-perceived outcome measures following unicompartmental knee arthroplasty with mini-incision. Int Orthop. 2004;28:286–289.
Koskinen E, Paavolainen P, Eskelinen A, Pulkkinen P, Remes V. Unicondylar knee replacement for primary osteoarthritis: a prospective follow-up study of 1,819 patients from the Finnish Arthroplasty Register. Acta Orthop. 2007;78:128–135.
Laurencin CT, Zelicof SB, Scott RD, Ewald FC. Unicompartmental versus total knee arthroplasty in the same patient: a comparative study. Clin Orthop Relat Res. 1991;273:151–156.
Lim HC, Bae JH, Song SH, Kim SJ. Oxford phase 3 unicompartmental knee replacement in Korean patients. J Bone Joint Surg Br. 2012;94:1071–1076.
Macaulay W, Yoon RS. Fixed-bearing, medial unicondylar knee arthroplasty rapidly improves function and decreases pain: a prospective, single-surgeon outcomes study. J Knee Surg. 2008;21:279–284.
Miskovsky C, Whiteside LA, White SE. The cemented unicondylar knee arthroplasty: an in vitro comparison of three cement techniques. Clin Orthop Relat Res. 1992;284:215–220.
Newman J, Pydisetty RV, Ackroyd C. Unicompartmental or total knee replacement: the 15-year results of a prospective randomised controlled trial. J Bone Joint Surg Br. 2009;91:52–57.
Niinimaki TT, Murray DW, Partanen J, Pajala A, Leppilahti JI. Unicompartmental knee arthroplasties implanted for osteoarthritis with partial loss of joint space have high re-operation rates. Knee. 2011;18:432–435.
Pandit H, Gulati A, Jenkins C, Barker K, Price AJ, Dodd CA, Murray DW. Unicompartmental knee replacement for patients with partial thickness cartilage loss in the affected compartment. Knee. 2011;18:168–171.
Pandit H, Jenkins C, Barker K, Dodd CA, Murray DW. The Oxford medial unicompartmental knee replacement using a minimally-invasive approach. J Bone Joint Surg Br. 2006;88:54–60.
Polkowski GG 2nd, Ruh EL, Barrack TN, Nunley RM, Barrack RL. Is pain and dissatisfaction after TKA related to early-grade preoperative osteoarthritis? Clin Orthop Relat Res. 2013;471:162–168.
Schroer WC, Barnes CL, Diesfeld P, LeMarr A, Ingrassia R, Morton DJ, Reedy M. The Oxford Unicompartmental Knee fails at a high rate in a high-volume knee practise. Clin Orthop Relat Res. 2013;471:3533–3539.
Scott CE, Howie CR, MacDonald D, Biant LC. Predicting dissatisfaction following total knee replacement: a prospective study of 1217 patients. J Bone Joint Surg Br. 2010;92:1253–1258.
Skowronski J, Jatskewych J, Dlugosz J, Skowronski R, Bielecki M. The Oxford II medial unicompartmental knee replacement: a minimum 10-year follow-up study. Ortop Traumatol Rehabil. 2005;7:620–625.
The Australian National Joint Replacement Registry. Annual Report 2012. Available at: https://aoanjrr.dmac.adelaide.edu.au/annual-reports-2012. Accessed August 12, 2013.
The National Joint Registry of England, Wales and Northern Ireland. 9th Annual Report 2012. Available at: http://www.njrcentre.org.uk/njrcentre/Portals/0/Documents/England/Reports/9th_annual_report/NJR%209th%20Annual%20Report%202012.pdf. Accessed September 22, 2013.
The New Zealand Joint Registry. Thirteen Year Report: January 1999 to December 2011. Available at: http://nzoa.org.nz/system/files/NJR%2013%20Year%20Report.pdf Accessed August 10, 2013.
The Norwegian Arthroplasty Register. Annual Report 2011. Available at: http://nrlweb.ihelse.net/eng/Report_2010.pdf. Accessed August 10, 2013.
The Swedish Knee Arthroplasty Register. Annual Report 2012. Available at: http://www.knee.nko.se/english/online/uploadedFiles/117_SKAR_2012_Engl_1.0.pdf. Accessed August 10, 2013.
Wylde V, Blom AW. The failure of survivorship. J Bone Joint Surg Br. 2011;93:569–570.
Author information
Authors and Affiliations
Corresponding author
Additional information
Each author certifies that he or she, or a member of his or her immediate family, has no funding or commercial associations (eg, consultancies, stock ownership, equity interest, patent/licensing arrangements, etc) that might pose a conflict of interest in connection with the submitted article.
All ICMJE Conflict of Interest Forms for authors and Clinical Orthopaedics and Related Research editors and board members are on file with the publication and can be viewed on request.
This work was performed at the Department of Surgery, Oulu University Hospital, Oulu, Finland.
About this article
Cite this article
Niinimäki, T., Eskelinen, A., Mäkelä, K. et al. Unicompartmental Knee Arthroplasty Survivorship is Lower Than TKA Survivorship: A 27-year Finnish Registry Study. Clin Orthop Relat Res 472, 1496–1501 (2014). https://doi.org/10.1007/s11999-013-3347-2
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s11999-013-3347-2