Simultaneous measurements were made with the rottometer and Roentgen stereometric analysis (RSA) in five patients with implanted tantalum markers in the tibia and femur.
4 Too few tantalum markers in the tibia component.
The mean condition number (dispersion of the bone markers in the tibia) was 56 (SD 23; range 28 117).
The mean condition number (dispersion of the bone markers in the tibia) was 17.3 (range 9.7 30.1, SD 4.6).
The relative movements of the tibial component in relation to bone were recorded using the markers in the tibia as the fixed reference segment.
The upper limit for mean error of rigid-body fitting (a measure of marker stability) was set at 0.30, and it was actually 0.16 (95% CI: 0.12 0.20) for the markers in the tibia and 0.09 (CI: 0.06 0.12) for those in the implant.
At exposure levels encountered after environmental exposure, associations with bio-markers of cumulative dose (mainly lead in tibia) were stronger and more consistent than associations with blood lead levels.
Although our study design precluded us from any inferences of causality, our results suggest that pain medication (especially opioid) use remains high in tibia shaft fracture patients with nonunion and may be a marker for nonunions.
The method for determining the position of the tibial implant in the global coordinate system arises from the kinematic model where the tantalum markers in the tibial implant and the proximal tibia bone define two rigid bodies (segments).
There is no level cap in Tibia.
