Investigation of the Characteristics and Mechanism of Interosseous Membrane Injuries in Typical Maisonneuve Fracture

OBJECTIVES: Previous studies on the mechanism and scope of interosseous membrane injury in Maisonneuve fractures have been inconsistent. In order to better guide clinical treatment, the characteristics and mechanism of interosseous membrane injuries and proximal 1/3 fibular fracture in typical Maisonneuve fracture were investigated. METHODS: The study comprised 15 patients between January 2019 and June 2021 with Maisonneuve fracture. All patients received X‐ray and MRI examination of the calf and ankle joint, and CT scanning of the ankle joint. The injuries of medial structure, inferior tibiofibular syndesmosis, fibula, posterior malleolus, and interosseous membrane were evaluated. RESULTS: MR images of the calf showed that the injury of interosseous membrane (IOM) was from the syndesmosis to the proximal fibular fracture site in two patients, with a range of 32.3 and 29.8 cm, respectively. In the other 13 patients, the IOM rupture was not only confined to the distal third of the calf, but also close to the fibula fracture, and the IOM was intact between the two fracture sites. The range of distal IOM rupture was 3.7–12.2 cm, with an average of 8.06 ± 2.35 cm. The proximal IOM was completely ruptured from the fibular side at the site of the fibular fracture and the range was 4.1–9.1 (average: 6.75 ± 1.64) cm. The average length of the integrate middle segment of the IOM was 14.55 ± 4.11 (5.6–20.3) cm. MR images of the calf also showed partial rupture of the posterior tibial muscle at the ending point on the fibula in 15 cases, partial rupture of soleus muscle and flexor hallucis longus in seven cases. CONCLUSIONS: The rupture of the IOM was caused by a combination of abduction and external rotation violence. It was manifested in two forms, most of which was not only distal end but also near fibular fracture site ruptures with the middle part intact, and a few were ruptures of the IOM from the ankle to the near fibular fracture site. The tibialis posterior muscle may be related to the location of the fibular fracture.