The current standard technique for distal locking of intramedullary nails is the freehand technique. This requires an experienced surgeon in order to hit the hole correctly. Even if the procedure is performed quickly, the surgeon is exposed to radiation.

During the nail insertion there is almost no deformation of the nail in torsion and varus-valgus, but a small deformation can occur in the AP plane. SureLock allows simple, fast and precise distal locking despite this deformation, without making a hole in the anterior cortex, in long proximal femoral nails as the PFN, PFNA, and TFN and decreases surgeons exposure to radiation.

The OR technique has three main steps after the SureLock has been assembled and calibrated to the respective nail. First, the C-arm is rotated until it is in the exact same plane as the nail-aiming-arm construct. This is achieved by rotating the C-arm until the dotted line on the lateral side of the aiming arm is overlying the median line on the medial side of the aiming arm. This can be done either by eye or with exact calculation of the degrees using the scales on the aiming arm. Secondly, the aiming arm is tilted until it is lined up with the nail. This can again be done either by eye or by calculating the millimeters the aiming arm needs to be moved. Finally, drilling through the sleeve assembly and insertion of the screws.

The technique is easy to learn, simple to use, and so precise that even unexperienced surgeons can hit the distal hole on a first attempt. Furthermore, SureLock enables more working space for the surgeon since the C-arm does not need to be positioned perpendicular to nail (drilling not in axis with C-arm).

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