ArticlePloS one2018
Sex differences in muscle morphology of the knee flexors and knee extensors.
Article in PloS one, 2018. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 30 papers, 3 of them syntheses that pooled it.
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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.
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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.
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Who cites it
30 citing papers in PubMed, 3 syntheses or guidelines pooled it, 55 citations in OpenAlex.
- Associations between biomarkers and skeletal muscle function in individuals with osteoarthritis: a systematic review and meta-analysis.Arthritis research & therapy · 2024Pooled it
- Biomarkers associated with lower limb muscle function in individuals with sarcopenia: a systematic review.Journal of cachexia, sarcopenia and muscle · 2022Pooled it
- Pooled it
- Sex-Specific Cut-off Values for Respiratory Muscle Strength in Older Women: Screening Implications for Respiratory Sarcopenia.Journal of Korean medical science · 2026Article
- Sex-Specific Analysis of Quadriceps and Hamstring Strength Following Anterior Cruciate Ligament Reconstruction With or Without Meniscal Repair.Journal of functional morphology and kinesiology · 2026Article
- Sex Differences in Knee Flexor Strength and Limb Symmetry Across Different Strength Testing Conditions in Healthy Recreational Athletes.Journal of clinical medicine · 2026Article
- Time course and regional heterogeneity of hamstring muscle thickness after maximal concentric exercise in men and women.European journal of applied physiology · 2026Article
- Training and Detraining Effects of Eccentric Exercise and Static Stretching on Hamstring Aponeurosis Dimensions.Scandinavian journal of medicine & science in sports · 2026Article
- Bilateral diabetic Charcot neuroarthropathy of the knee in a young woman with diabetes suspected of Wolfram-like syndrome.Diabetology international · 2026Article
- Size of Biceps Femoris Long Head Muscle Is Related to Running Economy in Male Recreational Runners.Sports (Basel, Switzerland) · 2025Article
- Cleats May Be a Risk Factor for ACL Tears in Female Lacrosse and Soccer Players.Orthopaedic journal of sports medicine · 2025Article
- Tibial Anterior Cruciate Ligament Avulsion Fractures in Pediatric and Adult Populations: A Systematic Literature Review.Journal of clinical medicine · 2025Review
- Shape factor versus truncated cone-based quantification of quadriceps and hamstring muscle volumes-A choice between accuracy and precision.Physiological reports · 2025Article
- Effects of Postural Conditions During Magnetic Resonance Imaging on Thigh Muscle Size.Scandinavian journal of medicine & science in sports · 2024Article
- Sex differences in muscle morphology between male and female sprinters.Journal of applied physiology (Bethesda, Md. : 1985) · 2024Article
- Hamstrings and quadriceps muscle size and strength in female and male elite competitive alpine skiers.Frontiers in physiology · 2024Article
- A classification of the plantar intrinsic foot muscles based on the physiological cross-sectional area and muscle fiber length in healthy young adult males.Journal of foot and ankle research · 2023Article
- First Insights in the Relationship between Lower Limb Anatomy and Back Squat Performance in Resistance-Trained Males and Females.Bioengineering (Basel, Switzerland) · 2023Article
- Techniques and Applications of Lower Extremity Feminization and Masculinization.Transgender health · 2023Review
- Sex-Specific Brain Activations during Single-Leg Exercise.International journal of sports physical therapy · 2022Article
Corrections and comments
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Authors and funding
4 authors at 2 institutions in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
introductionFemales experience higher risk of anterior cruciate ligament (ACL) injuries; males experience higher risk of hamstring strain injuries. Differences in injury may be partially due to sex differences in knee flexor (KF) to knee extensor (KE) muscle size ratio and the proportional size of constituent muscles. PURPOSE: To compare the absolute and proportional size, and mass distribution, of individual KE and KF muscles, as well as overall size and balance (size ratio) of these muscle groups between the sexes.
methodsT1-weighted axial plane MR images (1.5T) of healthy untrained young males and females (32 vs 34) were acquired to determine thigh muscle anatomical cross-sectional area (ACSA). Maximal ACSA (ACSAmax) of constituent muscles, summated for KF and KE muscle groups, and the KF:KE ratio were calculated.
resultsFemales had 25.3% smaller KE ACSAmax (70.9±12.1 vs 93.6±10.3 cm2; P<0.001) and 29.6% smaller KF ACSAmax than males (38.8±7.3cm2 vs 55.1±7.3cm2; P<0.001). Consequently, females had lower KF:KE ACSA ratio (P = 0.031). There were sex differences in the proportional size of 2/4 KE and 5/6 KF. In females, vastus lateralis (VL), biceps femoris long-head (BFlh) and semimembranosus (SM) were a greater proportion and sartorius (SA), gracilis (GR) and biceps femoris short-head (BFsh) a smaller proportion of their respective muscle groups compared to males (All P<0.05).
conclusionSex differences in KF:KE ACSAmax ratio may contribute to increased risk of ACL injury in females. Sex discrepancies in absolute and proportional size of SA, GR, VL and BFlh may contribute further anatomical explanations for sex differences in injury incidence.
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Registered trials
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