lag screw


Also found in: Dictionary, Thesaurus, Legal, Financial, Encyclopedia, Wikipedia.

lag screw

one of several screws placed through bony fracture fragments to immobilize the fragments, used in repair of mandibular fractures.

lag screw

Orthopedics Any screw used to achieve interfragmental compression; LSs do not protect fractures from bending, rotation or axial loading forces, and other devices should be used to provide these functions. See Screw.
References in periodicals archive ?
Screw positions were evaluated with the lag screw and proximal bone fragment (head and neck) and the safest seemed to be inferior middle and inferior posterior positions.
Thus, lag screws, bolts or other "positive connection" devices are required.
Angle braces are fastened to concrete using expansion bolts, then lag screwed to a post or beam.
Numerous approaches have been proposed for stabilization of these fractures depending on the size and quality of the tuberosity fragment, including "classic" tension banding, lag screws, plates, and suture anchors with or without fracture fragment excision [1,4-6,10-14,16-21].
Madsen JE et al have stated that "Use of a TSP reduced the secondary lag screw sliding as compared with the conventional CHS without affecting fracture healing." (8)
The reduction of head and neck fragment was evaluated by Garden alignment index (GAI) and lag screw position was evaluated by tip apex distance (TAD) [11,12].
The lag screw joints in the second and third lumber elements from the bottom wall on the side of the load application are withdrawn vertically.
This paper reports the first case of cephalomedullary nail breakage in two points, the holes for the lag screw and the locking screw, related to nonunion of a subtrochanteric fracture and metal fatigue in a very active elderly female.
(4) Dynamic Hip Screw (DHS) is a lag screw, which is biomechanically superior to various compression hip screw systems developed during recent years (Regazzoni 1985).
Sliding of the lag screw in hip fracture fixation devices enables fracture consolidation and transmission of forces through the fracture site and, by this mechanism, enhances healing.
This System--which can be used in conjunction with other fixation devices--also includes a toothed washer for improved bone fixation and a lag screw design for secure compression.
In addition to the screws used in the joint test program, an additional wood screw (diameter of 2.86 mm or 0.112 in) and lag screw (diameter of 7.8 mm or 0.31 in) were included in the embedment test program.