Fig. 6From: Medial patellofemoral ligament reconstruction using a bone groove and a suture anchor at patellar: a safe and firm fixation technique and 3-year follow-up study a, b, c Safety angle according to Wiberg type classification. Safety angle becomes more and more vertical from type I to type III. d, e The difference between males’ and females’ safety angle. Males’ safety angle is larger than femalesBack to article page