title: Response to letter to the editor: "Cam impingement: defining the presence of a cam deformity by the alpha angle data from the CHECK cohort an Chingford cohort".
authors.affiliation: Department of Orthopaedics, Erasmus MC University Medical Centre, Rotterdam, The Netherlands. Electronic address: r.agricola@erasmusmc.nl.
authors.forename: R
authors.initials: R
authors.lastname: Agricola
authors.affiliation: Department of Orthopaedics, Erasmus MC University Medical Centre, Rotterdam, The Netherlands.
authors.forename: J H
authors.initials: JH
authors.lastname: Waarsing
authors.affiliation: Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, NIHR Musculoskeletal Biomedical Research Unit, University of Oxford, Nuffield Orthopaedic Centre, Oxford, England. Electronic address: geraint.thomas@ndorms.ox.ac.uk.
authors.forename: G E
authors.initials: GE
authors.lastname: Thomas
authors.affiliation: Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, NIHR Musculoskeletal Biomedical Research Unit, University of Oxford, Nuffield Orthopaedic Centre, Oxford, England. Electronic address: andrew.carr@ndorms.ox.ac.uk.
authors.forename: A J
authors.initials: AJ
authors.lastname: Carr
authors.affiliation: Department of Orthopaedics, Erasmus MC University Medical Centre, Rotterdam, The Netherlands. Electronic address: m.reijman@erasmusmc.nl.
authors.forename: M
authors.initials: M
authors.lastname: Reijman
authors.affiliation: Department of Orthopaedics, Erasmus MC University Medical Centre, Rotterdam, The Netherlands; Department of General Practice, Erasmus MC University Medical Centre, Rotterdam, The Netherlands. Electronic address: s.bierma-zeinstra@erasmusmc.nl.
authors.forename: S M A
authors.initials: SM
authors.lastname: Bierma-Zeinstra
authors.affiliation: Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, NIHR Musculoskeletal Biomedical Research Unit, University of Oxford, Nuffield Orthopaedic Centre, Oxford, England. Electronic address: sion.glyn-jones@ndorms.ox.ac.uk.
authors.forename: S
authors.initials: S
authors.lastname: Glyn-Jones
authors.affiliation: Department of Biomechanical Engineering, Delft University of Technology, Delft, The Netherlands; Department of Orthopaedics and Rheumatology, University Medical Centre Utrecht, Utrecht, The Netherlands. Electronic address: h.h.weinans@umcutrecht.nl.
authors.forename: H
authors.initials: H
authors.lastname: Weinans
authors.affiliation: Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, NIHR Musculoskeletal Biomedical Research Unit, University of Oxford, Nuffield Orthopaedic Centre, Oxford, England. Electronic address: nigel.arden@ndorms.ox.ac.uk.
authors.forename: N K
authors.initials: NK
authors.lastname: Arden
mesh_terms: D005260:Female; D057925:Femoracetabular Impingement / Q000473:pathology*; D006801:Humans; D008297:Male
keywords: Hip; cam deformity; cam impingement; definition; epidemiology; femoroacetabular impingement; osteoarthritis; threshold value