Precise and feasible measurements of lateral calcaneal lengthening osteotomies by radiostereometric analysis in cadaver feet

Abstract

ObjectivesLengthening osteotomies of the calcaneus in children are in general grafted with bone from the iliac crest. Artificial bone grafts have been introduced, however, their structural and clinical durability has not been documented. Radiostereometric analysis (RSA) is a very accurate and precise method for measurements of rigid body movements including the evaluation of joint implant and fracture stability, however, RSA has not previously been used in clinical studies of calcaneal osteotomies. We assessed the precision of RSA as a measurement tool in a lateral calcaneal lengthening osteotomy (LCLO).MethodsLCLO was performed in six fixed adult cadaver feet. Tantalum markers were inserted on each side of the osteotomy and in the cuboideum. Lengthening was done with a plexiglas wedge. A total of 24 radiological double examinations were obtained. Two feet were excluded due to loose and poorly dispersed markers. Precision was assessed as systematic bias and 95% repeatability limits.ResultsSystematic bias was generally below 0.10 mm for translations. Precision of migration measurements was below 0.2 mm for translations in the osteotomy.ConclusionRSA is a precise tool for the evaluation of stability in LCLO.Cite this article: Bone Joint Res 2015;4:78–83.

CT-based radiostereometric analysis for assessing midfoot kinematics: precision compared with marker-based radiostereometry

“…The RSA precision values in the present study ranged from 0.39-0.94 mm for translation and 1.0-1.7° for rotation. These results are fitting for the study setup and in accordance with previously published equivalent studies [9,10,25]. To further substantiate our results, the RSA control parameters indicate stable and consistent tantalum markers valid for reliable precision measurements.…”

Calcaneal cuboid joint motion and osteotomy stability in children one year after calcaneal lengthening osteotomy

“…We assumed that the osteotomy was stable one year after surgery; however we provide RSA data from the osteotomy as verification of no *GMFCS level 1. inducible displacement upon weight-bearing, and thus document that any recorded motion in the CCJ was not due to instabilty in the osteotomy, but occurred within the CCJ. The analysis criteria included a condition number of the markermodels of maximum 350 6,7 , a minimum of three markers within each marker-model throughout all scenes, and a rigid body error threshold of maximum 0.5 mm according to the standard settings in the analysis software. Repeatability/precision of the RSA measurements, assessed by double-examinations, is expressed as a coefficient of repeatability, CR = ±1.96*SD diff .…”

“…Recently, in an experimental study, marker-based radiostereometric analysis (RSA) was proven feasible and precise in measurements of stability in the CCJ with a precision below 0.5 mm for translations and below 2 • for rotations of the calcaneal and the cuboid bones. 6 We used radiostereometric analysis (RSA) without and with weight-bearing during one-legged stance to evaluate CCJ motion and CLO stability in paediatric patients one year after CLO for pes planovalgus.…”

A computer simulation protocol to assess the accuracy of a Radio Stereometric Analysis (RSA) image processor according to the ISO-5725

“…The Radio-Sterometric-Analysis (RSA) is a technique to evaluate the micro-motions between bones and prosthesis (Selvik, 1989;Bruni et al, 2015), or the modifications of the bones (Callary et al, 2012;Martinkevich et al, 2015). The uniplanar fluoroscopy (Catani et al, 2009) is used to evaluate the movements of bones and prosthesis during specific tasks (Lawrence et al, 2018;Lin et al, 2013).…”