Evidence map›Paper›PMID 42713985›Full record

ArticleActa orthopaedica2026

Association of preoperative flexion contracture and limited knee flexion with short-term patient-reported outcomes after medial unicompartmental knee arthroplasty.

Tomofumi Kinoshita, Kristine Ifigenia Bunyoz, Kristian R L Mortensen, Christian Bredgaard Jensen, Christian S Nielsen, Kirill Gromov, Anders Troelsen

Abstract read
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Article in Acta orthopaedica, 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

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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

7 authors.

Tomofumi KinoshitaDepartment of Orthopaedic Surgery, Copenhagen University Hospital Hvidovre, Copenhagen, Denmark; Department of Clinical Medicine, Copenhagen University, Copenhagen, Denmark; Department of Orthopaedic Surgery, Ehime University Graduate School of Medicine, Ehime, Japan. kinoshita8u10@gmail.com.ORCID 0000-0001-6469-4652
Kristine Ifigenia BunyozDepartment of Orthopaedic Surgery, Copenhagen University Hospital Hvidovre, Copenhagen, Denmark.
Kristian R L MortensenDepartment of Orthopaedic Surgery, Copenhagen University Hospital Hvidovre, Copenhagen, Denmark.ORCID 0000-0001-8174-4965
Christian Bredgaard JensenDepartment of Orthopaedic Surgery, Copenhagen University Hospital Hvidovre, Copenhagen, Denmark.ORCID 0000-0001-6984-6782
Christian S NielsenDepartment of Orthopaedic Surgery, Copenhagen University Hospital Hvidovre, Copenhagen, Denmark; Department of Clinical Medicine, Copenhagen University, Copenhagen, Denmark.
Kirill GromovDepartment of Orthopaedic Surgery, Copenhagen University Hospital Hvidovre, Copenhagen, Denmark; Department of Clinical Medicine, Copenhagen University, Copenhagen, Denmark.ORCID 0000-0002-8114-5193
Anders TroelsenDepartment of Orthopaedic Surgery, Copenhagen University Hospital Hvidovre, Copenhagen, Denmark; Department of Clinical Medicine, Copenhagen University, Copenhagen, Denmark.ORCID 0000-0003-0132-8182

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

background and purposeWe aimed to clarify whether preoperative flexion contracture (FC) and limited knee flexion in patients with anteromedial osteoarthritis (OA) were associated with postoperative outcomes in mobile-bearing medial unicompartmental knee arthroplasty (UKA).

methodsWe retrospectively evaluated all patients who underwent mobile-bearing medial UKA. Preoperative extension and flexion angles, and the Oxford Knee Score (OKS) and Forgotten Joint Score-12 (FJS) recorded preoperatively and at 3, 12, and 24 months, were assessed. Patients were categorized by preoperative extension (no FC, < 10°, ≥ 10°) and flexion angles (< 120°, ≥ 120°). Changes in OKS and FJS were compared using general linear models with adjustment for age, sex, body mass index, and preoperative scores.

results1,199 patients were included. Preoperatively, 85% of patients had full extension, 12% had < 10° FC, and 3.1% had ≥ 10° FC. Regarding flexion, 40% had < 120°, while 60% had ≥ 120°. At 12 months, the < 10° FC group showed greater improvements than the ≥ 10° FC group in OKS (adjusted mean difference, 5.5 points; 95% confidence interval [CI] 0.9-10.2; P = 0.01) and FJS (17.0 points; CI 1.0-33.0; P = 0.03). The < 120° flexion group showed greater FJS improvement than the ≥ 120° flexion group (adjusted mean difference, 4.8 points; CI 0.1-9.6; P = 0.045). At 24 months, the CIs for all between-group differences included no difference.

conclusionMild preoperative FC and mild-to-moderately limited knee flexion were not associated with inferior outcomes. Patients with more pronounced FC showed slower recovery but still achieved the same increase in patient-reported outcome measures (PROMs) as those with mild FC.

Indexed as

Arthroplasty, Replacement, KneeContractureKnee JointOsteoarthritis, KneeAgedFemaleHumansMaleMiddle AgedPatient Reported Outcome MeasuresRange of Motion, ArticularRetrospective StudiesTreatment Outcome

Identifiers

PMID42713985
PMCPMC13555600

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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.