SLR-February 2014- Michael Corpuz
Reference: Davidovitch RI; Weil Y; Karia R et al. Intraoperative Syndesmotic Reduction: Three-Dimensional Versus Standard Fluoroscopic Imaging. J Bone Joint Surg Am. 2013 Oct 16:95 (20):1838-43.
Scientific Literature Review
Reviewed By: Michael Corpuz, DPM
Residency Program: Cedars-Sinai Medical Center, Los Angeles, CA
Podiatric Relevance: A crucial consideration in the outcome of ankle fractures with concomitant syndesmotic injury is the quality of the syndesmosis reduction. This therapeutic, Level II study compares the accuracy of reductions with standard fluoroscopy versus CT imaging.
Methods: Patients with either preoperative or intraoperative evidence of syndesmotic diastasis (via Cotton hook test and/or manual external rotation stress test) and underwent syndesmotic fixation at one of two Level 1 trauma centers were included. Fluoroscopic measurements indicative of a syndesmotic injury included a tib-fib clear space > 5 mm, tib-fib overlap < 10 mm on an AP view, or tib-fiboverlap < 1 mm on a mortise view. Center A utilized CT imaging, and Center Bused standard fluoroscopy for reduction. Postoperative axial CT scans were used to assess the accuracy/alignment of the reductions performed, implementing three specific and quantifiable measurements: anterior fibular distance, posterior fibular distance, and anterior translation distance.
Results: (n = 36; Ctr A =16, Ctr B = 20). Using ≥ 2 mm as the criteria for “displacement,” malrotation rates were exceedingly high, whether initially reduced with the aid of CT imaging or standard fluoroscopy. The following are the percentage of malreductions in each variable group (Ctr A vs. Ctr B) under each CT parameter: anterior fibular distance (38 percent vs. 30 percent), anterior translation distance (31 percent vs. 25 percent). The only instance where CT imaging was demonstrated to be a superior modality to standard fluoroscopy was in the malrotation rates in posterior fibular distance (6 percent vs. 40 percent). Using ≥ 1 mm as the threshold for displacement, malrotation rates were even higher throughout tall groups: anterior fibular distance (69 percent vs. 70 percent), anterior translation distance (50 percent vs. 55 percent), posterior fibular distance (38 percent vs. 60 percent).
Conclusions: The results of this comparative study highlight the notion that not only are there high rates of syndesmotic malreduction following operative treatment, but also demonstrates that advanced intraoperative imaging modalities (i.e. CT3-dimensional imaging) do not aid in significantly reducing malrotation rates.