Table 2

Outcome measures

Primary outcome measure
 Deformity indexAssessment of femoral head sphericity on pelvic radiograph
Secondary outcome measures
 Extrusion indexAssessment of femoral head subluxation/coverage on pelvic radiograph
 Faces Pain ScaleOrdinate scale for pain level
 Hip range of motionClinical examination
 Modified Harris hip scoreQuestionnaires for hip pain, associated symptoms, daily living and sports activities
 PODCIPain, physical function and impact on the child’s psyche
 Hip MRIPerfusion of the femoral epiphysis
 Bone ageAssessment on hand radiograph
  • PODCI, Global Paediatric Outcomes Data Collection Instrument questionnaires.