Sternal instability measured with radiostereometric analysis. A study of method feasibility, accuracy and precision.

ABSTRACT:

Background

A small, but unstable, saw-gap may hinder bone-bridging and induce development of painful sternal dehiscence. We propose the use of Radiostereometric Analysis (RSA) for evaluation of sternal instability and present a method validation.

Methods

Four bone analogs (phantoms) were sternotomized and tantalum beads were inserted in each half. The models were reunited with wire cerclage and placed in a radiolucent separation device. Stereoradiographs (n = 48) of the phantoms in 3 positions were recorded at 4 imposed separation points. The accuracy and precision was compared statistically and presented as translations along the 3 orthogonal axes. 7 sternotomized patients were evaluated for clinical RSA precision by double-examination stereoradiographs (n = 28).

Results

In the phantom study, we found no systematic error (p > 0.3) between the three phantom positions, and precision for evaluation of sternal separation was 0.02 mm. Phantom accuracy was mean 0.13 mm (SD 0.25). In the clinical study, we found a detection limit of 0.42 mm for sternal separation and of 2 mm for anterior-posterior dislocation of the sternal halves for the individual patient.

Conclusion

RSA is a precise and low-dose image modality feasible for clinical evaluation of sternal stability in research.

Trial registration

ClinicalTrials.gov Identifier: NCT02738437 , retrospectively registered.

SUBMITTER: Vestergaard RF 

PROVIDER: S-EPMC5960092 | biostudies-literature | 2018 May

REPOSITORIES: biostudies-literature