Fig. 1From: A cadaveric study of the location and morphology of the central patellar ridge for bone-patellar tendon-bone graftAnatomy picture of the patella according to Wiberg’s classification. a Type I, the facets are concave, symmetrical, and of equal size. b Type II, the medial facet is smaller than the lateral facet. c Type III, the convex medial facet is markedly smaller than the concave lateral facet, and the angle between the medial and lateral facets is nearly 90°Back to article page