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12Distal locking with screws

Verification of locking screw placement

In all cases, obtain final x-rays in two planes in order to check the exact locking screw placement. If the normal tight coupling between the nail and the insertion guide has been altered, the screws might have been placed either anterior or posterior to the nail.

Pitfall: too long a locking screw
It is important to remember that the distal femur tapers from the posterior to the anterior. Therefore, if a straight AP view is obtained, the locking screws appear to be inside the bone. If they appear to be outside the bone, they are most likely too long and will invariably cause pain and possibly heterotopic ossification. In order to assess the exact length of the locking screws an AP view can be obtained with 30° internal rotation of the lower extremity.