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difference in the postoperative Gissane angle between the 2
phases (115.9 vs 116.2, P = .898). In this study, we expected
a significant difference in the Böhler angle between the 2
groups, but the result was not significant (P = .079).
To our knowledge, this is the first comprehensive statistical analysis of the learning curve for ORIF of DIACF by
the extensile lateral approach, and it provides additional
information for novices who are interested in starting their
own practice. We suggest practicing in approximately 20
cases of ORIF for DIACF to be experienced, and it also
seems necessary to examine appropriate advice from
experts and practice through various media. This study has
some limitations. The main weaknesses of the present study
include its retrospective nature and the small sample size.
The study is based on data from a single surgeon, and therefore its generalizability is not known. The absence of postoperative CT for more accurate assessment of intra-articular
gap and step-off is a limitation. Furthermore, the selection
of the parameters defining the quality of reduction might
not be established. The operating surgeon performed the
radiographic measurement and categorized the quality of
the operative reconstruction. Nevertheless, this study can be
used to overcome the methodological weakness of existing
methods and applied to more objective and comprehensive
statistical methods.

Conclusion
As indicated by multidimensional statistical analyses overcoming the weakness of existing methodology, primary
technical competence in improving the reduction quality of
DIACF was achieved after the initial learning period with
20 cases. After the learning curve for ORIF of DIACF, a
better reduction quality in the sum of the reduction parameters was observed.
Acknowledgments
Special thanks to professor Chang Woo Kim for statistical advice.
He is the colorectal surgeon who inspired the authors based on his
achievements in the Department of Colorectal Surgery.

Declaration of Conflicting Interests
The author(s) declared no potential conflicts of interest with
respect to the research, authorship, and/or publication of this article. ICMJE forms for all authors are available online.

Funding
The author(s) received no financial support for the research,
authorship, and/or publication of this article.

ORCID iDs
Jungtae Ahn, MD,
https://orcid.org/0000-0002-4530-0512
Tae Yong Kim, MD,
https://orcid.org/0000-0002-3849-8006
Bi O Jeong, MD, PhD,
https://orcid.org/0000-0002-9881-2319

Foot & Ankle International 40(9)
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https://www.orcid.org/0000-0002-4530-0512 https://www.orcid.org/0000-0002-3849-8006 https://www.orcid.org/0000-0002-9881-2319

Foot & Ankle International - September 2019

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