I feel like they're the same thing. Sprained syndesmotic ligaments, sprained deltoid and fractured fibula. So why is the maisonneuve fracture its own thing?
The Maisonneuve fracture is a special form of the Weber C fracture. What makes it special is that the fracture of the fibula has to be localized within the proximal third of the fibula shaft (see "The Maisonneuve fracture is a spiral fracture of the proximal third of the fibula", http://www.ncbi.nlm.nih.gov/pubmed/23079149). Weber C includes all localizations of the fracture of the fibula.