Pre-existing patellofemoral disease does not affect 10-year survivorship in fixed bearing unicompartmental knee arthroplasty
- 29 Downloads
The purpose of this study was to assess 10-year functional outcome and survivorship analysis of patients with significant radiographic evidence of patellofemoral joint arthritis treated with fixed bearing unicompartmental knee arthroplasty.
Two hundred and sixteen patients (263 knees) that underwent UKA from 2003 to 2005 for a mean of 10.5 ± 2.1 years were prospectively followed up. Preoperative radiological assessment of the patellofemoral joint state was assessed according to the Ahlback classification by an independent assessor and radiographically significant patellofemoral disease was defined as grade 2 or more. Patients with significant bone-on-bone contact in the patellofemoral joint were excluded.
Of the 263 knees, 222 (84.4%) had normal patellofemoral joint state and 41 (15.6%) radiologically significant patellofemoral disease. At 10 years’ follow-up, the normal and patellofemoral groups had similar OKS (20 ± 7 vs 20 ± 8, n.s.) and KSS scores (79 ± 20 vs 81 ± 20, n.s.), respectively. There were 12 revision surgeries in the normal group and the most common indication for revision was progression of contralateral compartment osteoarthritis (6 of 12 cases). There was only one revision in the patellofemoral group and it was due to progression of contralateral compartment osteoarthritis (n.s.). When all secondary surgeries to the operated knee were considered as failures, the 10-year survival rate was 95.1% (CI 95%: 92.2–97.7%).
The presence of significant preoperative radiological patellofemoral disease does not affect long-term implant survival and patients have excellent functional outcomes 10 years postoperatively. These patients should not be contraindicated from undergoing unicompartmental knee arthroplasty.
Level of evidence
KeywordsUKA Patellofemoral Unicompartmental Arthroplasty Survivorship
LW analysed the data and wrote the paper. CYJ contributed significantly to statistical design and data analysis. CHC collected and managed the data. PHN revised and approved the manuscript. TKJ revised and approved the manuscript. CSL revised and approved the manuscript. LNN revised and approved the manuscript. YSJ conceived the study, revised and approved the manuscript.
This study was approved by the Singhealth Centralised Institutional Review Board (CIRB) committee (CIRB:2016/2144).
Compliance with ethical standards
Conflict of interest
No benefits in any form have been received or will be received from a commercial party related directly or indirectly to the subject of this article.
All authors and their immediate family did not receive any financial payments or other benefits from any commercial entity related to the subject of this article.
- 3.Ahlback S (1968) Osteoarthrosis of the knee. A radiographic investigation. Acta Radiol Diagn (Stockh) Suppl 277:7–72Google Scholar
- 17.Goodfellow JW, O’Connor J (1986) Clinical results of the Oxford knee: surface arthroplasty of the tibiofemoral joint with a meniscal bearing prosthesis. Clin Orthop Relat Res 205:21–42Google Scholar
- 18.Goodfellow J, O’Connor J, Dodd CAF, Murray DW (2006) Unicompartmental arthroplasty with the Oxford Knee. Oxford University Press, New York, pp 117–128Google Scholar
- 20.Hamilton TW, Pandit HG, Maurer DG, Ostlere SJ, Jenkins C, Mellon SJ, Dodd CAF, Murray DW (2017) Anterior knee pain and evidence of osteoarthritis of the patellofemoral joint should not be considered contraindications to mobile-bearing unicompartmental knee arthroplasty: a 15-year follow-up. Bone Jt J 99-B(5):632–639CrossRefGoogle Scholar
- 22.Insall JN, Dorr LD, Scott RD, Scott WN (1989) Rationale of the Knee Society clinical rating system. Clin Orthop Relat Res 248:13–14Google Scholar
- 27.Laurencin CT, Zelicof SB, Scott RD, Ewald FC (1991) Unicompartmental versus total knee arthroplasty in the same patient. A comparative study. Clin Orthop Relat Res 273:151–156Google Scholar
- 34.Robertsson O, Borgquist L, Knutson K, Lewold S, Lidgren L (1999) Use of unicompartmental instead of tricompartmental prostheses for unicompartmental arthrosis in the knee is a cost-effective alternative. 15,437 primary tricompartmental prostheses were compared with 10,624 primary medial or lateral unicompartmental prostheses. Acta Orthop Scand 70:170–175CrossRefGoogle Scholar
- 35.Rougraff BT, Heck DA, Gibson AE (1991) A comparison of tricompartmental and unicompartmental arthroplasty for the treatment of gonarthrosis. Clin Orthop Relat Res 273:157–164Google Scholar
- 37.Thein R, Zuiderbaan HA, Khamaisy S, Nawabi DH, Poultsides LA, Pearle AD (2015) Medial unicondylar knee arthroplasty improves patellofemoral congruence: a possible mechanistic explanation for poor association between patellofemoral degeneration and clinical outcome. J Arthroplasty 30(11):1917–1922CrossRefGoogle Scholar