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Using a screw placed in the central axis of the scaphoid into the subchondral bone
73%
3185/4392
Using a supplementary K-wire transfixing the distal pole of the scaphoid to the capitate
10%
441/4392
Using a screw placed in the dorsal axis of the scaphoid into the subchondral bone
5%
198/4392
Using a larger diameter screw placed in the dorsal axis of the scaphoid
8%
356/4392
Using a larger diameter screw placed in the volar axis of the scaphoid
4%
182/4392
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Several studies have shown a longer screw placed in the central axis of the scaphoid optimizes biomechanical fixation of scaphoid waist fractures. Many studies have discussed the amount of compression generated by various internal fixation screws (e.g headless vs. headed, variable pitch, partially vs. fully threaded, cannulated vs. noncannulated), but it is believed that rigidity of fixation is probably the most important factor in promoting healing of scaphoid fractures. The first reference by McCallister et al is a cadaveric, biomechanical study that demonstrated a centrally placed screw had 43% more stiffness than an eccentrically placed screw. They recommend using surgical techniques that optimize central placement and screw length, such as using a cannulated screw. The study by Dodds et al supported these findings and added that a longer screw with 2mm of bone coverage provided greater stability than a shorter screw. A more centrally placed screw is generally longer and has more length of screw on each side of the fracture than does a peripherally placed screw due to the anatomic dimensions of the scaphoid.
2.7
(51)
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