Abstract
AimThe correction accuracy of the Taylor Spatial Frame (TSF) fixator depends considerably on the precise determination of the mounting parameters (MP). Incorrect parameters result in secondary deformities that require subsequent corrections. Different techniques have been described to improve the precision of MP measurement, although exact calculation is reportedly impossible radiologically. The aim of this study was to investigate the accuracy of intraoperative and postoperative radiographic measurement methods compared to direct MP measurement from TSF bone mounting.MethodsA tibial Sawbone® model was established with different origins and reference ring positions. First, reference MPs for each origin were measured directly on the frame and bone using a calibrated, digital vernier calliper. In total 150 MPs measured with three different radiographic measurement techniques were compared to the reference MPs: digital radiographic measurements were performed using soft-copy PACS images without (method A) and with (method B) calibration and calibrated image intensifier images (method C).ResultsMPs measured from a non-calibrated X-ray image (method A) showed the highest variance compared to the reference MPs. A greater distance between the origin and the reference ring corresponded to less accurate MP measurements with method A. However, the MPs measured from calibrated X-ray images (method B) and calibrated image intensifier images (method C) were intercomparable (p = 0.226) and showed only minor differences compared to the reference values but significant differences to method A (p < 0,001).ConclusionThe results demonstrate that MPs can be accurately measured with radiographic techniques when using calibration markers and a software calibration tool, thus minimizing the source of error and improving the quality of correction.
Highlights
The Taylor Spatial Frame (TSF) is an external hexapod fixator that allows simultaneous correction of deformities in all six axes
mounting parameters (MP) measured from a non-calibrated X-ray image showed the highest variance compared to the reference MPs
The MPs measured from calibrated X-ray images and calibrated image intensifier images were intercomparable (p = 0.226) and showed only minor differences compared to the reference values but significant differences to method A (p < 0,001)
Summary
The Taylor Spatial Frame (TSF) is an external hexapod fixator that allows simultaneous correction of deformities in all six axes This is achieved by the movement of six telescopic struts connected to two rings that rotate and translate the bone segments around a virtual hinge. The accuracy of the calculation and thereby the correction result depends on accurate deformity parameters, frame parameters and mounting parameters (MPs). The latter define the location of the virtual hinge relative to the TSF reference ring (Fig. 1) [1]. We conducted this study to analyse the accuracy of postoperative and intraoperative radiographic measurement methods against direct measurement from the TSF mounted on a Sawbone® model. We sought to determine whether a surgeon can rely on radiographic measurement techniques as much as on direct measurement and –if any differences exist- which technique is the most precise
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
