155 / 245
DOS Kongressen 2016 ·
155
Methodological differences between studies of
clavicular bone shortening - A systematic review
Anders Thorsmark Høj, Lars Henrik Frich, Ole Maagaard, Søren Overgaard, Søren
Torp-Pedersen
Holbæk sygehus, department of orthopedic Surgery and Traumatology,
OUH/ den ortopæd kirurgiske forskningsenhed; Department of Orthopedic
Surgery and Traumatology, OUH; Holbæk sygehus, department of orthopedic
Surgery and Traumatology, Holbæk; Department of Orthopedic Surgery and
Traumatology, OUH; department of radiology , Glostrup hospital
Background:
Clavicular bone shortening is a relative indication for operative
treatment of acute clavicular fractures. Although it is a clinically accepted in-
dication, it is still scientifically contested. The reason for this is multifactorial.
However, as different measurement methods exist ( methods using fragment
overlap or side difference) and the possible bias of radiographic magnification;
there is a possibility that differences in methodology and magnification bias
could have caused these scientific differences. We wanted to investigate the
literature for differences in methodologies used and therefore designed a sys-
tematic review.
Purpose / Aim of Study:
Our objectives were (i) review studies on bone
shortening for differences in methodology specifically regarding measurement
method used. (ii) Estimate radiographic magnification in studies.
Materials and Methods:
To study methodological differences (i) we found 13
studies. For the estimation of radiographic magnification bias, we found (ii) 9
anatomical reference studies and five radiographic index studies.
Findings / Results:
We found that (i) measurement method used highly ef-
fected the study’s results and conclusions. Studies showing adverse effects of
shortening had mostly used the fragment overlap method whereas studies that
found shortening to be not harmful had used the side difference method. We
found that the majority of studies had highly underestimated the bias of radio-
graphic magnification and (ii) bias was estimated to be between 10-25% if not
adjusted for magnification.
Conclusions:
In conclusion, the scientific controversy of bone shortening
seems to be because of differences in methodologies - especially measurement
method used, and not only differences in results. Radiographic magnification is
much larger cause of bias than previously thought and should routinely be ad-
justed for.
No conflicts of interest reported
106.