[1] Maxima Med Ctr, Dept Orthopaed Surg & Trauma, Veldhoven, Netherlands
[2] Catharina Hosp, Dept Orthopaed Surg & Trauma, Eindhoven, Netherlands
[3] Dutch Hip Patient Assoc Vereniging Afwijkende Heu, Nijkerk, Netherlands
[4] Maastricht Univ Med Ctr, Dept Orthopaed Surg, Maastricht, Netherlands
[5] Sophia Childrens Univ Hosp, Dept Orthopaed & Sports Med, Erasmus MC, Rotterdam, Netherlands