Medial bicompartmental arthroplasty patients display more normal gait and improved satisfaction, compared to matched total knee arthroplasty patients

Abstract

Purpose Medial bicompartmental arthroplasty, the combination of ipsilateral medial unicompartmental and patellofemoral arthroplasty, is an alternative to total knee arthroplasty for patients with medial tibiofemoral and severe patellofemoral arthritis, when the lateral tibiofemoral compartment and anterior cruciate ligament are intact. This study reports the gait and subjective outcomes following medial bicompartmental arthroplasty. Methods Fifty-five subjects were measured on the instrumented treadmill at top walking speeds, using standard metrics of gait. Modular, single-stage, medial bicompartmental arthroplasty subjects (n = 16) were compared to age, body mass index, height- and sex-matched healthy (n = 19) and total knee arthroplasty (n = 20) subjects. Total knee arthroplasty subjects with pre-operative evidence of tricompartmental osteoarthritis or anterior cruciate ligament dysfunction were excluded. The vertical component of ground reaction force and temporospatial measurements were compared using Kruskal–Wallis, then Mann–Whitney test with Bonferroni correction (α = 0.05). Oxford Knee and EuroQoL EQ-5D scores were compared. Results Objectively, the medial bicompartmental arthroplasty top walking speed of 6.7 ± 0.8 km/h was 0.5 km/h (7%) slower than that of healthy controls (p = 0.2), but 1.3 km/h (24%) faster than that of total knee arthroplasty subjects (5.4 ± 0.6 km/h, p < 0.001). Medial bicompartmental arthroplasty recorded more normal maximum weight acceptance (p < 0.001) and mid-stance forces (p = 0.03) than total knee arthroplasty subjects, with 11 cm (15%) longer steps (p < 0.001) and 21 cm (14%) longer strides (p = 0.006). Subjectively, medial bicompartmental arthroplasty subjects reported Oxford Knee Scores of median 41 (interquartile range 38.8–45.5) compared to total knee arthroplasty Oxford Knee Scores of 38 (interquartile range 30.5–41, p < 0.02). Medial bicompartmental arthroplasty subjects reported EQ-5D median 0.88 (interquartile range 0.84–0.94) compared to total knee arthroplasty median 0.81 (interquartile range 0.73–0.89, p < 0.02.) Conclusion This study finds that, in the treatment of medial tibiofemoral osteoarthritis with severe patellofemoral arthritis, medial bicompartmental arthroplasty results in nearer-normal gait and improved patient-reported outcomes compared to total knee arthroplasty. Level of evidence III.

Image-based robot assisted bicompartmental knee arthroplasty versus total knee arthroplasty

“…In addition, some studies have shown reduced intraoperative blood loss and thereby lower post-op blood transfusion rates in BCKA compared to TKA owing to less bone resection and soft tissue resection [17,18]. Gait analysis on a treadmill by Garner et al [19] has demonstrated an advantage of BCKA over TKA in top walking speeds and stride length as well owing to retention of the anterior cruciate ligament.…”

Load transfer in bone after partial, multi-compartmental, and total knee arthroplasty

“…For example, it was assumed that TKA tibiofemoral joint reaction force data are relevant to PKA and CPKA, or that ligament forces estimated for the native knee are transferable to a PKA implanted knee. This may not be the case as differences in gait kinetics and kinematics have been observed; for example, UKA patients have been observed to walk faster than TKA patients (Wiik et al, 2013;Jones et al, 2016;Agarwal et al, 2019), as have patients with Bi-UKA (Garner et al, 2021c) and BCA-M (Garner et al, 2021e); however, the muscle loads were not changed to account for this. While these assumptions did not prevent our data replicating known clinical trends, or from correlating with prior laboratory work, there are likely subtle impacts that may have occurred.…”

“…CPKA allows for the preservation of a wellfunctioning, well-fixed PKA in these cases (Garner et al, 2021f), or an alternative primary procedure for the one-in-three patients with bicompartmental knee disease (Garner et al, 2019;Stoddart et al, 2021). CPKA is associated with favorable patient outcomes (Biazzo et al, 2018;Wada et al, 2020;Garner et al, 2021e;Garner et al, 2021f;Garner et al, 2021b), stability (Garner et al, 2021d), and function (Wang et al, 2018;Garner et al, 2021b;Garner et al, 2021) compared to TKA. However, it is not known how use of multiple PKAs in the same knee affects load transfer to bone.…”