Lateral (or external) snapping hip:
This is localised at the lateral aspect of the hip and is produced by the tensor fascia lata or the abducting fibres of gluteus maximus sliding over the greater trochanter and producing a characteristic snapping sound.
This is not usually painful
The young dancer (and the parent) require reassurance that this does not signify any bony abnormality
Internal Snapping Hip:
This is caused by the iliopsoas tendon as it flips over the iliopectineal eminence.
The patient complains of pain with hip flexion
References
Image from OpenI – Licensed by CC
Image from OpenI – Licensed by CC
Image from OpenI – Licensed by CC