ArticleEuropean radiology2017
Cam deformity and the omega angle, a novel quantitative measurement of femoral head-neck morphology: a 3D CT gender analysis in asymptomatic subjects.
Article in European radiology, 2017. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 18 papers.
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Who cites it
18 citing papers in PubMed, 42 citations in OpenAlex.
- Wide variations in the alpha angle reporting of the hip in asymptomatic individuals-a systematic review.Journal of hip preservation surgery · 2026Review
- How Common Is Femoroacetabular Impingement Morphology in Asymptomatic Adults? A 3D CT-Based Insight into Hidden Risk.Journal of clinical medicine · 2025Article
- Article
- A combination of acetabular coverage and femoral head-neck measurements can help diagnose femoroacetabular impingement.Journal of hip preservation surgery · 2022Article
- Extent of Cam Resection Relative to Epiphyseal Line and Its Association With Clinical Outcomes After Arthroscopic Treatment for Femoroacetabular Syndrome.Orthopaedic journal of sports medicine · 2022Article
- MRI-based synthetic CT shows equivalence to conventional CT for the morphological assessment of the hip joint.Journal of orthopaedic research : official publication of the Orthopaedic Research Society · 2022Article
- Automated Morphometric Analysis of the Hip Joint on MRI from the German National Cohort Study.Radiology. Artificial intelligence · 2021Article
- The Lisbon Agreement on Femoroacetabular Impingement Imaging-part 3: imaging techniques.European radiology · 2021Article
- The Lisbon Agreement on femoroacetabular impingement imaging-part 2: general issues, parameters, and reporting.European radiology · 2021Article
- The Lisbon Agreement on Femoroacetabular Impingement Imaging-part 1: overview.European radiology · 2020Review
- Advances in FAI Imaging: a Focused Review.Current reviews in musculoskeletal medicine · 2020Review
- CT texture analysis of acetabular subchondral bone can discriminate between normal and cam-positive hips.European radiology · 2020Article
- Hip arthroscopy for lateral cam morphology: how important are the vessels?Journal of hip preservation surgery · 2020Review
- Quantifying differences in femoral head and neck asphericity in CAM type femoroacetabular impingement and hip dysplasia versus controls using radial 3DCT imaging and volumetric segmentation.The British journal of radiology · 2020Article
- 3D CT segmentation of CAM type femoroacetabular impingement-reliability and relationship of CAM lesion with anthropomorphic features.The British journal of radiology · 2018Article
- A new quantitative 3D approach to imaging of structural joint disease.Scientific reports · 2018Article
- Arthroscopic versus open treatment of cam-type femoro-acetabular impingement: retrospective cohort clinical study.International orthopaedics · 2018Article
- Hip shape is symmetric, non-dependent on limb dominance and gender-specific: implications for femoroacetabular impingement. A 3D CT analysis in asymptomatic subjects.European radiology · 2018Article
Corrections and comments
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Authors and funding
6 authors at 4 institutions in 2 countries.
Funding
No grant is acknowledged in the PubMed record.
Abstract
objectiveOur objectives were to use 3D computed tomography (CT) to define head-neck morphologic gender-specific and normative parameters in asymptomatic individuals and use the omega angle (Ω°) to provide quantification data on the location and radial extension of a cam deformity.
methodsWe prospectively included 350 individuals and evaluated 188 asymptomatic hips that underwent semiautomated CT analysis. Different thresholds of alpha angle (α°) were considered in order to analyze cam morphology and determine Ω°. We calculated overall and gender-specific parameters for imaging signs of cam morphology (Ω° and circumferential α°).
resultsThe 95 % reference interval limits were beyond abnormal thresholds found in the literature for cam morphology. Specifically, α° at 3/1 o´clock were 46.9°/60.8° overall, 51.8°/65.4° for men and 45.7°/55.3° for women. Cam prevalence, magnitude, location, and epicenter were significantly gender different. Increasing α° correlated with higher Ω°, meaning that higher angles correspond to larger cam deformities.
conclusionHip morphometry measurements in this cohort of asymptomatic individuals extended beyond current thresholds used for the clinical diagnosis of cam deformity, and α° was found to vary both by gender and measurement location. These results suggest that α° measurement is insufficient for the diagnosis of cam deformity. Enhanced morphometric evaluation, including 3D imaging and Ω°, may enable a more accurate diagnosis. KEY POINTS: • 95% reference interval limits of cam morphotype were beyond currently defined thresholds. • Current morphometric definitions for cam-type morphotype should be applied with care. • Cam prevalence, magnitude, location, and epicenter are significantly gender different. • Cam and alpha angle thresholds should be defined according to sex/location. • Quantitative 3D morphometric assessment allows thorough and reproducible FAI diagnosis and monitoring.
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