Evidence map›Paper›PMID 40621988›Full record

ArticleKnee surgery, sports traumatology, arthroscopy : official journal of the ESSKA2025

Restoration of the trochlear peaks is unnecessary with a kinematic alignment-optimized femoral component as under-stuffing results in equivalent or better patient-reported outcome scores.

Stephen M Howell, Ahmed Zabiba, Patrick Sadoghi, Alexander J Nedopil, Maury L Hull

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Article in Knee surgery, sports traumatology, arthroscopy : official journal of the ESSKA, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 2 papers.

0numbers the graph read from it
0cells of the map it votes in
2citing papers in PubMed
–field-weighted citation impact
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

The trial behind it

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Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

2 citing papers in PubMed.

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4 · The record

Corrections and comments

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

5 authors.

Stephen M HowellDepartment of Biomedical Engineering, University of California, Davis, California, USA.ORCID https://orcid.org/0000-0001-8184-0324
Ahmed ZabibaUniversity of California at Davis School of Medicine, Sacramento, California, USA.ORCID https://orcid.org/0009-0001-6352-9871
Patrick SadoghiDepartment of Orthopedics and Trauma, Medical University of Graz, Graz, Austria.ORCID https://orcid.org/0000-0003-1767-555X
Alexander J NedopilOrthopädische Klinik König-Ludwig-Haus, Lehrstuhl für Orthopädie der Universität Würzburg, Würzburg, Germany.ORCID https://orcid.org/0000-0002-3655-158X
Maury L HullDepartment of Orthopedic Surgery, University of California, Davis, California, USA.ORCID https://orcid.org/0000-0001-8305-4589

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

purposeKinematic alignment (KA) total knee arthroplasty (TKA) aligns the femoral component to restore the pre-arthritic posterior joint line, potentially altering the heights of the medial and lateral trochlear peaks. It remains unclear whether the femoral component should be adjusted to correct deviations in peak height. This study assessed whether >2 mm of under- or over-stuffing in peak height negatively impacted patient-reported outcome (PRO) scores compared to restoration within ±2 mm.

methodsThe study included 115 KA TKAs performed with a KA-optimized femoral component featuring a trochlea with a lateral ridge opening that creates a 20° valgus trochlear groove and a flattened medial ridge, and PROs at a mean of 22 (12-28) months. The surgeon measured the height of the trochlear peaks on the anterior femoral resection.

resultsPeak under-stuffing >2 mm occurred medially in 66% and laterally in 43%. Over-stuffing >2 mm was too infrequent for statistical analysis. Compared to restoration within ±2 mm, medial under-stuffing resulted in a non-equivalent 6-point higher Forgotten Joint Score (FJS) (p = 0.1087) and equivalent but 9- and 3-point higher Knee Injury and Osteoarthritis Outcome Score for Joint Replacement (KOOS JR) (p < 0.0001) and Oxford Knee Score (OKS) (p = 0.0020). Lateral under-stuffing yielded equivalent but 6-, 12- and 3-point higher FJS (p = 0.0484), KOOS JR (p < 0.0001) and OKS (p < 0.0001).

conclusionThe KA-optimized femoral component features a patient-specific trochlea that addresses anterior arthritic trochlear variations, which are reported to range from -24° varus to 30° valgus. One possible explanation for why >2 mm of under-stuffing leads to superior PROs is that reducing the peak height compensates for over-stuffing above the native trochlea caused by the prosthesis's proximal overreach, with a reported average of 17 mm. LEVEL OF EVIDENCE: Level III.

Indexed as

Arthroplasty, Replacement, KneeFemurKnee ProsthesisOsteoarthritis, KneePatient Reported Outcome MeasuresAgedAged, 80 and overBiomechanical PhenomenaFemaleHumansKnee JointMaleMiddle AgedProsthesis DesignRetrospective StudiesForgotten Joint Scorekinematic alignmentover‐stuffingpatellofemoral kinematicsprosthetic trochlear groovetrochlear peak height

Identifiers

PMID40621988
PMCPMC12684351

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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.