Evidence map›Paper›PMID 41580764›Full record

ArticleArthritis research & therapy2026

Knee muscle strength as a mediator of sex differences in incident knee osteoarthritis.

Xiaoxiao Li, Ziying Wu, Yuqing Zhang, Chao Zeng, Guanghua Lei, Jie Wei, Jiatian Li, Yongbing Xiao

Abstract read
In one paragraph

Article in Arthritis research & therapy, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

0numbers the graph read from it
0cells of the map it votes in
0citing papers in PubMed
–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.

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

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

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

0 citing papers in PubMed.

No citing paper in PubMed yet.

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

8 authors.

Xiaoxiao Li *Hunan Key Laboratory of Joint Degeneration and Injury, Xiangya Hospital Central South University, Changsha, China.
Ziying Wu *Department of Orthopaedics, Xiangya Hospital Central South University, 87 Xiangya Road, Changsha, Hunan, 410008, China.
Yuqing ZhangDepartment of Medicine, Division of Rheumatology, Allergy, and Immunology, Massachusetts General Hospital, Boston, USA.
Chao ZengHunan Key Laboratory of Joint Degeneration and Injury, Xiangya Hospital Central South University, Changsha, China.
Guanghua LeiHunan Key Laboratory of Joint Degeneration and Injury, Xiangya Hospital Central South University, Changsha, China.
Jie WeiHunan Key Laboratory of Joint Degeneration and Injury, Xiangya Hospital Central South University, Changsha, China.
Jiatian LiDepartment of Orthopaedics, Xiangya Hospital Central South University, 87 Xiangya Road, Changsha, Hunan, 410008, China.
Yongbing XiaoHunan Key Laboratory of Joint Degeneration and Injury, Xiangya Hospital Central South University, Changsha, China. xiaoyongbing5994@csu.edu.cn.

Funding

Central South University Innovation-Driven Research Program 2023CXQD031National Key Research and Development Program of China 2022YFC2505500National Key Research and Development Program of China 2022YFC3601900, 2022YFC3601901National Natural Science Foundation of China 82430081, U21A20352National Natural Science Foundation of China 82472524National Natural Science Foundation of China, China 82072502, 82372474Natural Science Foundation of Hunan Province 2022JJ20100Natural Science Foundation of Hunan Province, China 2023JJ30951Scientific Research Program of FuRong Laboratory 2023SK2100
6 · The paper itself

Abstract

backgroundFemales have a higher risk of incident knee osteoarthritis (KOA) than males, particularly in the lateral compartment; however, the underlying mechanisms remain unclear. We investigated whether knee flexor and extensor strength mediate the association between sex and lateral radiographic and symptomatic KOA risk.

methodsThis cohort study utilized data from the Osteoarthritis Initiative, a longitudinal prospective study of participants aged 45–79 years. We included knees without radiographic or symptomatic KOA at baseline. Knee extensor and flexor strength were measured isometrically using a validated device (Good Strength Chair) and normalized to body mass index. Mediation analyses were performed using marginal structural models to assess the contribution of knee flexor and extensor strength to the relationship between sex and the risk of lateral radiographic and symptomatic KOA, adjusting for age, race, knee injury history, physical activity, knee alignment, cartilage volume, and hormone therapy.

resultsA total of 5,126 eligible knees from 3,056 participants without radiographic KOA and 6,773 from 3,720 participants without symptomatic KOA were identified at baseline. Among 5,126 knees without radiographic KOA, the 8-year risks of lateral radiographic KOA were 5.9% in females and 3.4% in males, with an odds ratio (OR) of 1.72 (95% confidence interval [CI]: 1.28 to 2.31). The indirect effects of female sex on lateral radiographic KOA via flexors and extensor strength were OR = 1.14 (95% CI: 1.04 to 1.26) and 1.16 (95% CI: 1.05 to 1.27), respectively. The direct effects (not mediated through flexor/extensor strength) were OR = 1.48 (95% CI: 1.01 to 1.95) and 1.46 (95% CI: 1.01 to 1.92). Knee flexor and extensor strength mediated 31.1% and 33.9% of the total effect of sex on lateral radiographic KOA risk, respectively. Similar results were also observed for incident lateral symptomatic KOA.

conclusionThe lateral radiographic and symptomatic KOA risk is higher in females than males, partly mediated by lower flexor and extensor strength. These findings suggest that enhancing knee flexor and extensor strength in females may help reduce their risk of developing lateral radiographic and symptomatic KOA.

Indexed as

Knee JointMuscle StrengthOsteoarthritis, KneeSex CharacteristicsAgedCohort StudiesFemaleHumansIncidenceLongitudinal StudiesMaleMiddle AgedProspective StudiesRisk FactorsSex FactorsCohort studyKnee strengthMediation effectOsteoarthritisSex

Identifiers

PMID41580764
PMCPMC12910961

What OpenQuestion holds

Textmetadata
LicenceCC BY-NC-ND
Read underepoch 390

Registered trials

None linked

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.