JMIR Publications

ABSTRACT

Background:

Fifth metatarsal fractures are one of the most common foot fractures, of which 11-25% concern Dancer’s fractures (distal spiral fractures). Conservative therapy in a cast as well as operative treatment have both been opted as preferred modes of treatment in the limited literature available. However, we often see healing problems such as delayed and non-union when treated non-operatively, leading to a need for secondary intervention. Therefore, in our institution, treatment has changed over the years from predominantly conservative to mostly operative. To investigate whether our hypothesis holds up that primary surgical treatment is beneficial, this retrospective study is designed.

Objective:

The objective of the study is to compare differences in outcomes (delayed/non-union) of conservative versus operative treatment of patients with Dancer’s type fracture.

Methods:

A retrospective comparative cohort study, taking place in a level II trauma center (Zaandam Medical Center). Patients with a Dancer’s fracture in the period of 2012-2021 will be included and divided into two cohorts: conservative (2012-2015) versus operative (2016-2021). Primary outcome is difference in percentage of delayed/non-union. Secondary outcomes are percentage of primary conservative treatment failure, needing secondary operative treatment, complications (infection, hardware failure) and functional outcome. If 118 patients are included in each group, sufficient power is expected to be reached depending on the age-distribution of patients. Percentage delayed/non-union between two groups is calculated and statistically compared using Chi-Square (χ2) statistics. Logistic regression analysis will be used to investigate possible associations between patient characteristics and failed conservative treatment. A Mann-Whitney-U test will be used to compare functional outcome between groups. An independent T-test will be used to compare the means of SF-12 scores when normally distributed and a Wilcoxon rank sum test when non-normally distributed.

Results:

2134 potentially relevant health insurance codes have been extracted from the hospital’s register. We expect to find a total of 236 Dancer’s fractures in this dataset.

Conclusions:

This study has its limitations due to it being single center and data collection is performed retrospectively. However, it covers a large time period and provides the possibility to show treatment outcome differences in two reasonably large cohorts, which has not been done for this type of injury in literature before. If our hypothesis is endorsed by this study, we plan to do a prospective randomized controlled trial to further corroborate the hypothesis that Dancer’s fractures benefit from surgery.