Screw positioning and
lag screw cut-out reasons are discussed in many studies.
[6,16] Nevertheless, the
lag screw has potential to rotate the rotationally unstable femoral head during its insertion [14,25], a factor that may increase the incidence of aseptic necrosis and nonunion [23].
Sunderamoorthy, "Anterior or posterior obliquity of the
lag screw in the lateral view-Does it affect the sliding characteristics on unstable trochanteric fractures?" Injury, vol.
The second method of bone healing is direct bone healing, and is facilitated in an environment of absolute stability provided by
lag screws and compression plating.
In order to ensure failure would occur in the bolt or
lag screw, oversized fasteners were used to attach the joist hangers.
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Lag Screws. The
lag screw is a large-diameter long screw used for anchoring structural members.
The wooden mailbox pictured at right, purchased at a Bay Area nursery, is mounted atop a 6-foot-tall 4-by-4 redwood post and secured with a 3-inch-long
lag screw. Tucked in a perennial bed within easy reach of a path, it keeps tools close by when spent blooms need clipping.
Lag screw fixation has been advocated when the tuberosity fragment is large enough to allow the placement of at least two screws [4].
A 5-hole barrel plate fixed to
lag screw and fixed to shaft of femur using cortical screws in 2nd and 5th hole of plate.
The major development is the unique design and thread spacing of the
lag screw which provides better resistance to cutout.
The system provides for
lag screw fixation for comminuted patterns, non-locking screws to obtain compression across simple patterns and locking fixation in osteopenic bone and multi-fragmentary fracture patterns.
After reduction and fixation of the talus with cancellous
lag screws was achieved, the medial malleolus fracture was fixed with a combination of a distal
lag screw followed by the application of the anti-glide plate situated over the apex of the fracture.