Journal of orthopaedic trauma
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Comparative Study
Stability of open-book pelvic fractures using a new biomechanical model of single-limb stance.
A new biomechanical model of single-limb stance was developed to test the stability of intact, injured, and internally fixed pelves. ⋯ This model of single-limb stance suggests that a single symphyseal plate across the pubic symphysis can stabilize the open-book injury under short-term quasi-static loads.
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Comparative Study
Hip screw augmentation with an in situ-setting calcium phosphate cement: an in vitro biomechanical analysis.
This study was performed to determine whether a new, in situ-setting calcium phosphate cement would have sufficient mechanical integrity to reinforce compression screw fixation of unstable intertrochanteric fractures. We compared the cut-out resistance of screws augmented with calcium phosphate cement to the cut-out resistance of screws augmented with polymethylmethacrylate (PMMA). We used PMMA as the standard for comparison because it is currently used clinically. Our hypothesis was that initial fixation strength with PMMA and calcium phosphate cement augmentation would not be significantly different from one another. ⋯ The in situ-setting calcium phosphate cement investigated in this study compared favorably with PMMA in a single-cycle cut-out test of augmented compression hip screws in senile trabecular bone. Our results suggest that these materials may have promise as substitutes for PMMA in the salvage of compression hip screw fixation in elderly osteopenic patients with complex intertrochanteric fractures and that further study of their use in this application is warranted.
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To report on the early complications related to the percutaneous placement of iliosacral screws for the operative treatment of displaced posterior pelvic ring disruptions. ⋯ Iliosacral screw fixation of the posterior pelvis is difficult. The surgeon must understand the variability of sacral anatomy. Quality triplanar fluoroscopic imaging of the accurately reduced posterior pelvic ring should allow for safe iliosacral screw insertions. Anticipated noncompliant patients or those with craniocerebral trauma may need supplementary posterior pelvic fixation. Low rates of infection, blood loss, and nonunion can be expected.
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To characterize the prevalence, morphology, and prognosis of anterior (transolecranon) fracture-dislocations of the elbow. ⋯ Anterior elbow dislocations occur most often as a fracture-dislocation in which the distal humerus is driven through the olecranon, thereby causing a complex, comminuted fracture of the proximal ulna. This injury is frequently confused with anterior Monteggia lesions by virtue of the readily apparent radiocapitellar dislocation. Stable restoration of the appropriate contour and dimensions of the trochlear notch of the ulna will lead to a good result in most cases.
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Comparative Study
Biomechanical comparison of fixation methods in transverse olecranon fractures: a cadaveric study.
Our null hypothesis was that no difference in fracture displacement would be detected between traditional monofilament wire and Kirschner wire placement versus three modified tension-band techniques for transverse olecranon fractures. ⋯ In transverse noncomminuted olecranon fractures, fixation with monofilament wire is superior with Kirschner wire placement into the anterior ulnar cortex. With intramedullary Kirschner wires, fixation using braided cable is significantly improved over that with monofilament wire. When using braided cable, figure-eight and circular loop designs allow similar displacements. Braided cable or anterior cortical Kirschner wire purchase increases the stability of fixation over that achieved with the traditional method.