Evidence map›Paper›PMID 42192572›Full record

ArticleJournal of orthopaedic surgery and research2026

Biomechanical consequences of minor medial joint line elevation after medial unicompartmental knee arthroplasty.

Yao Xu, Zuling Yi, Yingkai Zhang, Naicheng Diao, Heyong Yin, Yike Dai

Abstract read
In one paragraph

Article in Journal of orthopaedic surgery and research, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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1 · What the graph read from it

What it found

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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

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3 · Its place in the literature

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4 · The record

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5 · Who and what money

Authors and funding

6 authors.

Yao XuDepartment of Orthopedic Surgery, Beijing Friendship Hospital, Capital Medical University, No 95 Yong'an Road, Xicheng, Beijing, 100050, P.R. China.
Zuling YiDepartment of Orthopedic Surgery, Beijing Friendship Hospital, Capital Medical University, No 95 Yong'an Road, Xicheng, Beijing, 100050, P.R. China.
Yingkai ZhangDepartment of Orthopedic Surgery, Beijing Friendship Hospital, Capital Medical University, No 95 Yong'an Road, Xicheng, Beijing, 100050, P.R. China.
Naicheng DiaoDepartment of Orthopedic Surgery, Beijing Friendship Hospital, Capital Medical University, No 95 Yong'an Road, Xicheng, Beijing, 100050, P.R. China.
Heyong YinDepartment of Orthopedic Surgery, Beijing Friendship Hospital, Capital Medical University, No 95 Yong'an Road, Xicheng, Beijing, 100050, P.R. China.
Yike DaiDepartment of Orthopedic Surgery, Beijing Friendship Hospital, Capital Medical University, No 95 Yong'an Road, Xicheng, Beijing, 100050, P.R. China. dai_yike@126.com.

Funding

Beijing Natural Science Foundation L244020Beijing Science and Technology Program Project F20240923166049
6 · The paper itself

Abstract

backgroundMedial joint line elevation (JLE) commonly occurs during unicompartmental knee arthroplasty (UKA), but its biomechanical effects remain unexplored. This study addresses this gap by evaluating the biomechanical consequences of global JLE across different range of flexion angles.

methodsA three-dimensional finite element model of the knee was constructed from CT and MRI data and validated against published experimental data. Medial fixed-bearing UKA was simulated with three joint line conditions (native, + 1 mm, and + 2 mm global elevation) at four flexion angles (0°, 30°, 60°, 90°), resulting in 12 models. All models were subjected to physiological axial loads simulating daily activities for comparative biomechanical analysis.

resultsThe biomechanical impact of JLE was profoundly dependent on flexion angle and was mediated by induced coronal plane alignment changes. At full extension (0°), JLE triggered a compensatory valgus shift, increasing lateral compartment stress. During mid‑flexion (30° and 60°), a varus alignment trend led to a paradoxical "biphasic effect"-lateral cartilage stress decreased, while medial polyethylene insert stress increased, peaking with a 12.4% rise at 60° under 2 mm elevation. A critical finding was a sharp "stress concentration peak" in the tibial cancellous bone beneath the prosthesis at 60° flexion with 2 mm JLE, where stress surged by 55.5%. At 90° flexion, the pattern shifted again, with JLE re‑inducing a valgus trend and elevating lateral stress toward physiological levels.

conclusionThis study reveals a novel, angle-dependent biomechanical cascade triggered by minor JLE, driven by dynamic alignment changes. Precise joint line restoration and avoidance of repetitive 60° flexion weight-bearing are suggested as potential considerations for surgical practice and postoperative rehabilitation, although this remains a hypothesis that requires clinical validation.

Indexed as

Arthroplasty, Replacement, KneeKnee JointBiomechanical PhenomenaFinite Element AnalysisHumansMagnetic Resonance ImagingRange of Motion, ArticularTomography, X-Ray ComputedWeight-BearingAlignmentbiomechanicsFinite element analysisJoint line elevationUnicompartmental knee arthroplasty

Identifiers

PMID42192572
PMCPMC13403401

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LicenceCC BY-NC-ND
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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.