that would be appropriate for rotation of the insert 1 upon reaching the pivot point the sleeve 32 is retracted as shown in fig9 b and the instrument 30 is moved medially to impart the initial rotation at this point the instrument 30 is tamped slightly to impart a small amount of rotation to the insert 1 having been positioned as shown in fig9 c the sleeve 32 is advanced such that a corner portion 44 on the sleeve 32 makes contact with the first end portion of the insert 1 the further advancement of sleeve 32 will result in the rotation of insert 1 about the post 26 which is retained in position by arm 34 additional tamping of the instrument 30 may be necessary the sleeve 32 is advanced until the insert is rotated into its final position as shown in fig9 d at this point the sleeve 32 is retracted and the mating surfaces 42 are withdrawn from engagement with the first end portion 10 as shown in fig9 e the instrument 30 is then manipulated such that the post 26 is removed from recess 46 and the instrument 30 is then released from the insert 1 at this point the instrument 30 is removed from the prepared site bone growth material is provided in.