Use of an aiming drill guide and ankle arthroscopy for reduction of depressed articular surface in posterior malleolar fractures

Purpose: We describe a novel technique that uses an aiming drill guide and ankle arthroscopy for direct visualization and reduction of the depressed articular surface located between the posterior tibia and the fractured posterior malleolus. This technique requires less soft tissue dissection to visualize and reduce the depressed articular surface. Methods: Between June 2014 and May 2019, 126 patients were surgically treated for trimalleolar fractures. Among them, 11 had depressed articular fragment between the posterior tibia and the fractured posterior malleolus reduced using our novel technique. The study included six men and five women, with a mean age of 46.5 (range: 23–62) years. Results: In eight (73%) cases, the articular surface was reduced, with the articular surface step-off being less than 2 mm, as noted on postoperative computed tomography (CT). Syndesmosis congruity within an anterior-to-posterior difference of less than 2 mm was confirmed in nine (82%) cases via postoperative CT. The mean 100-mm visual analog scale (VAS) and the mean Olerud-Molander ankle score at the final follow-up were 16.6 ± 14.5 and 87.7 ± 7.5, respectively. Conclusions: The depressed articular fragment located between the posterior tibia and the fractured posterior malleolus can be treated using an aiming drill guide and ankle arthroscopy. Ankle arthroscopy is used for direct visualization of the depressed articular surface, and the aiming drill guide can guide the bone plunger precisely to the depressed articular surface for reduction. This technique requires less soft tissue dissection than conventional techniques to visualize and reduce the depressed articular surface.