Clinical biomechanics
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Clinical biomechanics · Oct 2008
Comparative StudyBiomechanical evaluation of different fixation methods for fracture dislocation involving the proximal tibia.
Fracture dislocations of the knee involving the proximal tibia are difficult to treat because of the operative approach that maybe required and the instability of the construct. The optimal fixation method of these fractures remains controversial, improper fixations usually lead to an unsatisfactory prognosis. The purpose of this study was to compare the mechanical strength of four different fixation constructs for this kind of fracture. ⋯ This study suggests that the medial double plates technique is biomechanically the best fixation method for fracture dislocations involving the proximal tibia, while lateral locked plate technique is not indicated to this kind of fracture due to its insufficient stability.
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Clinical biomechanics · Oct 2008
Validation of a computer navigation system and a CT method for determination of the orientation of implanted acetabular cup in total hip arthroplasty: a cadaver study.
Successful hip reconstruction to restore the normal hip biomechanics requires precise placement of implants. Computer assisted navigation in total hip arthroplasty has been proposed to have the potential to help achieve a high accuracy in implant placement. The goal of the study was to evaluate the accuracy of an imageless computer navigation system on cadavers and to validate a non-invasive computed tomography method for post-operative determination of acetabular cup orientation. ⋯ While the values for cup orientation determined with imageless computer navigation were comparable to those from direct bone and implant digitization, the measurement for anteversion obtained was not as accurate as that for abduction. The proposed computer tomography-model method has an excellent intra-rater consistency for experienced raters, as well as an excellent overall inter-rater consistency. The study confirms that a non-invasive computed tomography based model analysis can be used in clinical practice as a valid method for post-operatively evaluating the orientation of the acetabular component.