Table 1: Groups of experiment

	IM	C2	C3	L2	L3
IM	+	+	+	+	+
plate	-	+	+	+	+
The type of screw	-	Bicortical - common screws	Bicortical - common screws	Unicortical - locking screws	Unicortical - locking screws
The number of screw	-	2	3	2	3