Evidence mapPaperPMID 40910379Full record

ArticleKnee surgery, sports traumatology, arthroscopy : official journal of the ESSKA2026

Posterior femoral condylar morphology following mechanical vs. kinematic alignment using a medial-pivot implant designed for mechanical alignment: A CT-based comparative study.

Yohei Ohyama, Yukihide Minoda, Sho Masuda, Ryo Sugama, Hideki Ueyama, Hidetomi Terai

Abstract readComparative Study
In one paragraph

Article in Knee surgery, sports traumatology, arthroscopy : official journal of the ESSKA, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 1 paper, 1 of them a synthesis that pooled it.

0numbers the graph read from it
0cells of the map it votes in
1citing papers in PubMed, 1 pooled it
field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

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2 · The registry

The trial behind it

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3 · Its place in the literature

Who cites it

1 citing paper in PubMed, 1 synthesis or guideline pooled it.

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4 · The record

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PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

6 authors.

Yohei OhyamaDepartment of Orthopaedic Surgery, Osaka Rosai Hospital, Osaka, Japan.ORCID https://orcid.org/0000-0003-4681-7481
Yukihide MinodaDepartment of Orthopaedic Surgery, Osaka Metropolitan University Graduate School of Medicine, Osaka, Japan.ORCID https://orcid.org/0000-0002-1939-8288
Sho MasudaDepartment of Orthopaedic Surgery, Osaka Metropolitan University Graduate School of Medicine, Osaka, Japan.ORCID https://orcid.org/0009-0006-4306-8592
Ryo SugamaDepartment of Orthopaedic Surgery, Osaka Metropolitan University Graduate School of Medicine, Osaka, Japan.ORCID https://orcid.org/0000-0003-3084-8443
Hideki UeyamaDepartment of Orthopaedic Surgery, Osaka Metropolitan University Graduate School of Medicine, Osaka, Japan.ORCID https://orcid.org/0000-0003-4155-9508
Hidetomi TeraiDepartment of Orthopaedic Surgery, Osaka Metropolitan University Graduate School of Medicine, Osaka, Japan.ORCID https://orcid.org/0000-0001-9183-3363

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

purposeThe kinematic alignment (KA) technique aims to restore native joint anatomy; however, the extent to which it restores posterior femoral condylar morphology after total knee arthroplasty (TKA) remains unclear. The posterior longitudinal overhang in the femoral condyle (PLOF) has been reported to affect clinical outcomes. This study aimed to compare the PLOF after medial pivot TKA performed using KA and mechanical alignment (MA) techniques.

methodsThis retrospective computed tomography-based study included 50 knees (from 25 men and 25 women) with medial knee osteoarthritis who underwent unilateral TKA. Femoral component-computer-aided design (FC-CAD) models of a medial-pivot prosthesis originally engineered for MA were positioned on preoperative computed tomography images according to KA and MA protocols. The primary outcomes were medial and lateral PLOF, defined as the sagittal overhang of the FC-CAD model beyond the native bone contour. The extent of distal and posterior femoral resections and correlations among femoral morphological parameters, including femoral valgus, lateral distal femoral, and condylar twist angles, and the PLOF were analysed.

resultsThe mean medial and lateral PLOF associated with KA was significantly greater (3.8 ± 1.4 vs. 3.2 ± 2.0 mm; p = 0.002) and smaller (3.4 ± 1.6 vs. 4.1 ± 1.9 mm; p < 0.001), respectively, than those associated with MA. Compared with KA, MA decreased valgus alignment and added external rotation. The PLOF associated with KA and femoral morphological parameters was not significantly correlated.

conclusionsThe KA resulted in significantly different ( > 3 mm) medial and lateral PLOF compared with the MA. The lack of correlations between the KA-associated PLOF and femoral morphological parameters suggests a native-prosthetic morphological mismatch. Surgeons should consider strategic downsizing when an MA-oriented medial-pivot FC is implanted using KA or employ KA-specific implants to optimise clinical outcomes. LEVEL OF EVIDENCE: Level III, retrospective comparative study.

Indexed as

Arthroplasty, Replacement, KneeFemurKnee JointKnee ProsthesisOsteoarthritis, KneeAgedBiomechanical PhenomenaComputer-Aided DesignFemaleHumansMaleMiddle AgedProsthesis DesignRetrospective StudiesTomography, X-Ray Computedkinematic alignmentmechanical alignmentmorphology of the posterior femoral condylesposterior longitudinal overhang in the femoral condyletotal knee arthroplasty

Identifiers

PMID40910379
PMCPMC12948348

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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 Socratic graph.