Evidence map›Paper›PMID 41540497›Full record

ArticleBMC sports science, medicine & rehabilitation2026

Step-down biomechanics in unilateral patellofemoral pain: a cross-sectional study of young females.

Xikai Lin, Ruixiong Chen, Peng Chen, Huiwu Zuo, Junpeng Song, Jiawei Zheng, Jian Chen, Xiaofang Cheng

Abstract read
In one paragraph

Article in BMC sports science, medicine & rehabilitation, 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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0citing papers 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

8 authors.

Xikai LinPain management and Tuina Department, Beijing University of Chinese Medicine Shenzhen Hospital (Longgang), No.1 Dayun Road, Shenzhen, Longgang, P.R. China.
Ruixiong ChenDepartment of Rehabilitation Medicine, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, P.R. China.
Peng ChenSchool of Exercise and Health, Shanghai University of Sport, Shanghai, P.R. China.
Huiwu ZuoSchool of Exercise and Health, Shanghai University of Sport, Shanghai, P.R. China.
Junpeng SongHubei Gymnastics Program Administrative Center, Wuhan, Hubei, P.R. China.
Jiawei ZhengEngineering Research Center of Sports Health Intelligent Equipment of Hubei Province, Wuhan Sports University, Wuhan, P.R. China.
Jian ChenEngineering Research Center of Sports Health Intelligent Equipment of Hubei Province, Wuhan Sports University, Wuhan, P.R. China. 57247028@qq.com.
Xiaofang ChengPain management and Tuina Department, Beijing University of Chinese Medicine Shenzhen Hospital (Longgang), No.1 Dayun Road, Shenzhen, Longgang, P.R. China. 779068057@qq.com.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

backgroundDespite extensive research on biomechanical abnormalities in the affected lower limb of young women with patellofemoral pain (PFP) during step-down tasks, the presence of such abnormalities in the unaffected limb remains unclear. This study aims to fill the gap in existing literature by investigating bilateral biomechanics in this population, with the goal of providing an evidence base for targeted rehabilitation and preventive strategies. METHODS​​: In this cross-sectional study using purposive sampling, 16 young females with unilateral PFP and 16 healthy controls, all aged 18–30 years, underwent three-dimensional joints angles and torques assessments of the hip, knee, and ankle during step-down tasks. Three valid trials were collected per lower limb, with analyses focusing on the initial contact (IC) and peak vertical ground reaction force (vGRF) moments. RESULTS​​: No significant differences were found between the bilateral limbs of the CON group. At the IC moment, the unaffected limb of the PFP group showed greater hip adduction than the affected limb (P = 0.016). At the peak vGRF moment, the unaffected limb exhibited larger hip adduction and internal rotation angles (P = 0.021 and P = 0.044), along with greater hip abduction and knee valgus torques (P = 0.032 and P = 0.04). Compared to the CON group, the PFP group’s affected limb had a smaller hip flexion angle at IC (P = 0.021). Moreover, the unaffected limb of the PFP group showed smaller hip flexion and abduction angles (P = 0.016 and P = 0.003). At the peak vGRF moment, the affected limb of the PFP group exhibited smaller hip flexion and larger plantarflexion angles (P = 0.042 and P = 0.023). The unaffected limb in the PFP group had smaller hip flexion, abduction, and external rotation angles (P = 0.042, P = 0.005, and P = 0.042), and larger plantarflexion angles (P < 0.001). CONCLUSION​​: Young females with unilateral PFP exhibited compensatory biomechanical alterations in the unaffected limb. Prolonged overuse without timely intervention may increase joint stress and lead to long-term dysfunction. Early bilateral intervention such as hip abduction and external rotation muscle training is essential to prevent such complications. CLINICAL TRIAL NUMBER​​: Not applicable.

Identifiers

PMID41540497
PMCPMC12892557

What Socratic holds

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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 Socratic graph.