ReviewOrthopaedic journal of sports medicine2020
Classifying Cam Morphology by the Alpha Angle: A Systematic Review on Threshold Values.
Review in Orthopaedic journal of sports medicine, 2020. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 46 papers, 1 of them a synthesis that pooled it.
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Who cites it
46 citing papers in PubMed, 1 synthesis or guideline pooled it.
- Cam morphology and the risk of developing radiographic hip osteoarthritis within 8 years: an individual participant data meta-analysis of 23 886 hips from the world COACH consortium.British journal of sports medicine · 2026Pooled it
- Effect of Preoperative Opioid Consumption on Outcomes After Hip Arthroscopy for Femoroacetabular Impingement and Labral Tears: A Minimum 2-Year Follow-up Study.Orthopaedic journal of sports medicine · 2026Article
- Prevalence of Cam Femoroacetabular Lesions in Medieval (1200-1600 CE) and Postmedieval (1600-1850 CE) Dutch Skeletal Collections.Arthroscopy, sports medicine, and rehabilitation · 2026Article
- Evaluating the Association Between Core Muscle Injury Symptom Pattern and Concomitant Femoroacetabular Impingement Syndrome.Orthopaedic journal of sports medicine · 2026Article
- Asymmetric bony hip morphology in asymptomatic professional baseball pitchers: a cross-sectional cohort study.BMC sports science, medicine & rehabilitation · 2026Article
- Cam morphology and the development of femoroacetabular impingement syndrome and hip osteoarthritis.Nature reviews. Rheumatology · 2026Review
- Defining the postoperative alpha angle threshold for improved outcomes in posterolateral cam lesions.Hip international : the journal of clinical and experimental research on hip pathology and therapy · 2026Article
- Is Femoral Head Bone Marrow Edema of Unknown Etiology Associated with Acetabular Overcoverage? A CT-Based Three-Dimensional Study.Tomography (Ann Arbor, Mich.) · 2026Article
- Relationship between pelvic incidence and hip, pelvic, and lumbar motion during squatting in healthy individuals with high and low pelvic incidence.Scientific reports · 2026Article
- Wide variations in the alpha angle reporting of the hip in asymptomatic individuals-a systematic review.Journal of hip preservation surgery · 2026Review
- Associated Factors of Primary Cam Morphology in 4477 Early Adolescents: A Multiethnic, Population-Based, Cross-sectional Study (Generation R).Orthopaedic journal of sports medicine · 2025Article
- Birmingham Royal Orthopedic Hospital (BROH) CAM Offset: A Simplified Metric for Detection of CAM Morphology of the Hip.The Indian journal of radiology & imaging · 2025Article
- Radiological outcome and complications after subcapital shortening osteotomy for the treatment of slipped capital femoral epiphysis- a case series.International orthopaedics · 2025Article
- A novel radiographic finding for estimation of the cortical-cancellous boundary: A magnetic resonance imaging case series of patients with femoroacetabular impingement.Journal of orthopaedics · 2025Article
- Hip Active Range of Motion in Patients with Femoroacetabular Impingement Syndrome.Sensors (Basel, Switzerland) · 2025Article
- Asymptomatic female softball pitchers have altered hip morphology and cartilage composition.Scientific reports · 2025Article
- Review of femoroacetabular impingement syndrome.Journal of hip preservation surgery · 2024Review
- Acetabular retroversion and cam morphology are contributing risk factors for posterior hip dislocation independent of the trauma mechanism.Archives of orthopaedic and trauma surgery · 2024Article
- Relationship Between Hip and Groin Pain and Hip Range of Motion in Amateur Soccer and Australian Rules Football Players.Orthopaedic journal of sports medicine · 2024Article
- Femoroacetabular impingement syndrome in middle-aged individuals is strongly associated with the development of hip osteoarthritis within 10-year follow-up: a prospective cohort study (CHECK).British journal of sports medicine · 2024Article
Corrections and comments
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Authors and funding
7 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
backgroundThe alpha angle is the most often used measure to classify cam morphology. There is currently no agreement on which alpha angle threshold value to use. PURPOSE: To systematically investigate the different alpha angle threshold values used for defining cam morphology in studies aiming to identify this threshold and to determine whether data are consistent enough to suggest an alpha angle threshold to classify cam morphology. STUDY
designSystematic review; Level of evidence, 3.
methodsThe Embase, Medline (Ovid), Web of Science, Cochrane Central, and Google Scholar databases were searched from database inception to February 28, 2019. Studies aiming at identifying an alpha angle threshold to classify cam morphology were eligible for inclusion.
resultsWe included 4 case-control studies, 10 cohort studies, and 1 finite-element study from 2437 identified publications. Studies (n = 3) using receiver operating characteristic (ROC) curve analysis to distinguish asymptomatic people from patients with femoroacetabular impingement syndrome consistently observed alpha angle thresholds between 57° and 60°. A 60° threshold was also found to best discriminate between hips with and without cam morphology in a large cohort study based on a bimodal distribution of the alpha angle. Studies (n = 8) using the upper limit of the 95% reference interval as threshold proposed a wide overall threshold range between 58° and 93°. When stratified by sex, thresholds between 63° and 93° in male patients and between 58° and 94° in female patients were reported.
conclusionBased on the available evidence, mostly based on studies using ROC curve analysis, an alpha angle threshold of ≥60° is currently the most appropriate to classify cam morphology. Further research is required to fully validate this threshold.
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