Puppe's rule is
Two fracture lines will never cross( puppe's rule) . Applying this rule it is easy to find out the sequence of injuries, i,e which fracture has occured first. Ref: FORENSIC MEDICINE AND TOXICOLOGY Dr PC IGNATIUS THIRD EDITION PAGE 162
Two fracture lines cross at right angles
Two fracture lines cross at acute angle
Two fracture lines never cross each other
Two fracture lines cross at obtuse angle
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