Fig. 2

Conversion of plotted points of contour of femoral head and neck in BoneFinder to circle of best fit using custom Python script. Panel A: Automated points applied to onto contour of bone using BoneFinder. Anatomically guided points: 0, 2, 9, 16, 19, 34, 37, 43, 47, 55, 65. Panel B: Points manually adjusted. Panel C: Output of Python script where the red points denote the agreed upon contour of the bone. A circle of best fit around the femoral head is depicted in blue that is fitted to points 19–32. The alpha angle is calculated between a line from the centre point of the circle (blue diamond) to the midpoint of femoral neck (green point, the midpoint of the narrowest section between points 2–15 and 37–49) and a line from the centre of the circle to the location on the femoral head/neck junction where the femur leaves the circle of best fit (green point)