What is this called?

[paisjpq]

depends which way the foot was going...
a horse with toe-out conformation will exhibit 'winging'--when the foot breaks over on the medial side of the foot and causes it to arc to the inside.
a horse with toe-in conformation will exhibit 'paddling'--where the foot will swing to the ouside as it leaves the ground.
probably dad passed on his front-end defect which is why they have the same action.