Comparing surgical strategies for end-stage anteromedial osteoarthritis

Abstract

Aims Treatment of end-stage anteromedial osteoarthritis (AMOA) of the knee is commonly approached using one of two surgical strategies: medial unicompartmental knee arthroplasty (UKA) or total knee arthroplasty (TKA). In this study we aim to investigate if there is any difference in outcome for patients undergoing UKA or TKA, when treated by high-volume surgeons, in high-volume centres, using two different clinical guidelines. The two strategies are ‘UKA whenever possible’ vs TKA for all patients with AMOA. Methods A total of 501 consecutive AMOA patients (301 UKA) operated on between 2013 to 2016 in two high-volume centres were included. Centre One employed clinical guidelines for the treatment of AMOA allowing either UKA or TKA, but encouraged UKA wherever possible. Centre Two used clinical guidelines that treated all patients with a TKA, regardless of wear pattern. TKA patients were included if they had isolated AMOA on preoperative radiographs. Data were collected from both centres’ local databases. The primary outcome measure was change in Oxford Knee Score (OKS), and the proportion of patients achieving the patient-acceptable symptom state (PASS) at one-year follow-up. The data were 1:1 propensity score matched before regression models were used to investigate potential differences. Results The matched cohort included 400 patients (mean age 67 years (SD 9.55), 213 (53%) female, mean BMI 30.2 kg/m2, 337 (84%) American Society of Anesthesiologists grade ≤ 2). We found a mean adjusted difference in change score of 3.02 points (95% confidence interval (CI) 1.41 to 4.63; p < 0.001) and a significantly larger likeliness of achieving PASS (odds ratio 3.67 (95% CI 1.73 to 8.45); p = 0.001) both in favour of the UKA strategy. Conclusion UKA and TKA are both good strategies for treating end-stage AMOA. However, when compared as a strategy, UKA achieved larger improvements in OKS, and were more likely to reach the PASS value at one-year follow-up. Cite this article: Bone Jt Open 2022;3(5):441–447.

Partial versus total knee arthroplasty for isolated antero-medial osteoarthritis – An analysis of PROMs and satisfaction

“…Mikkelsen et al compared outcomes (OKS) and the likelihood of patients attaining an acceptable clinical state (PASS) with both UKA and TKA for AMOA [ 42 ]. They reported higher odds of patients attaining the PASS cut-off of the OKS with UKA compared to TKA.…”

Short-Term Functional Outcomes of Unicompartmental versus Total Knee Arthroplasty in an Asian Population

“…The benefits of a UKA over a TKA are that it has lower morbidity, faster recovery, shorter length of stay, and better cost-effectiveness when compared to TKA [14,15]. These findings have been validated in recent studies [16][17][18]. In general, given a choice between UKA and TKA, most surgeons prefer UKA for younger patients who have less severe arthritis and a better pre-operative function.…”

Robot-assisted partial knee replacement versus standard total knee replacement (RoboKnees): a protocol for a pilot randomized controlled trial

“…Numerous studies have been conducted comparing TKA and partial knee replacements [ 7 – 19 ]. The research has found that UKA can lead to improved functional outcomes, but with higher revision rates [ 9 ], although some patients report less pain [ 17 ] and greater satisfaction [ 20 , 21 ]. Recent systematic reviews indicate that TKA generally provides better short-term outcomes, lower revision rates, and shorter operative times when compared to BiKA.…”