Inter-lock Screwdriver T25/3.5 mm Hex

In order to address a variety of clinical challenges associated with screw insertion during a MIO approach to fixation, a new self-holding screwdriver has been designed to facilitate screw insertion through small incisions. This is particularly useful in areas with large amounts of soft tissue and will greatly help avoid the risk of disengagement of the screw.

An essential part of fracture fixation is ensuring soft tissue protection which drives increasing numbers of surgeons to use MIO techniques and small, stab incisions for screw insertion with either plates or nail implants. Several difficulties have been reported alongside this technique including disengagement of the screw from the screwdriver, improper direction of screw insertion and lost screws in-situ. 

For the current T25 and 3.5 mm hex screwdrivers, an external holding sleeve is available to retain the screw. There are however certain disadvantages with the external holding sleeve such as difficulty in the handling procedure and the need for a larger incision for the proper insertion of the instrument.

The tips of the new Inter-lock Screwdrivers (T25/3.5 mm Hex) lock into the recesses of existing Synthes screws with a StarDrive 25 or 3.5 mm hexagonal recess (Fig 1). Wings were added to the nut for better grip when tightening the nut down to capture the screw (Fig 2). After insertion of the screw, no force is required to release the screw from the tip of the screwdriver. The screwdrivers are available in two lengths: 330 mm and 224 mm.

This new screwdriver will improve current screw insertion and removal when compared to previously available screwdrivers whilst also potentially decreasing required OR time for specific procedures.

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