The subgroups represent a variation within the group and the one illustrated is indicated with red in the text.
A1 Infrasyndesmotic lesion, isolated
.1 rupture of the lateral collateral ligament
.2 avulsion of the tip of the lateral malleolus
.3 transverse fracture of the lateral malleolus
A2 Infrasyndesmotic lesion, with fracture of the medial malleolus
.1 rupture of the lateral collateral ligament
.2 avulsion of the tip of the lateral malleolus
.3 transverse fracture of the lateral malleolus
A3 Infrasyndesmotic lesion, with postero-medial fracture
.1 rupture of the lateral collateral ligament
.2 avulsion of the tip of the lateral malleolus
.3 transverse fracture of the lateral malleolus
B1 Transsyndesmotic fibular fracture, isolated
.1 simple
.2 simple, with rupture of the anterior syndesmosis
.3 multifragmentary
B2 Transsyndesmotic fibular fracture, with medial lesion
.1 simple with rupture of the medial collateral ligament and rupture of the anterior syndesmosis
.2 simple with fracture of the medial malleolus and with rupture of the anterior syndesmosis
.3 multifragmentary
B3 Transsyndesmotic fibular fracture, with medial lesion and a Volkmann (fracture of the postero-lateral rim)
.1 fibula simple, with rupture of the medial collateral ligament
.2 fibula simple, with fracture of the medial malleolus
.3 fibula multifragmentary, with fracture of the medial malleolus
C1 Suprasyndesmotic lesion, diaphyseal fracture of the fibula, simple
.1 with rupture of the medial collateral ligament
.2 with fracture of the medial malleolus
.3 with fracture of the medial malleolus and a Volkmann (=Dupuytren)
C2 Suprasyndesmotic lesion, diaphyseal fracture of the fibula, multifragmentary
.1 with rupture of the medial collateral ligament
.2 with fracture of the medial malleolus
.3 with the fracture of the medial malleolus and a Volkmann (=Dupuytren)
C3 Suprasyndesmotic lesion, proximal fibular lesion
.1 without shortening, without Volkmann
.2 with shortening, without Volkmann
.3 medial lesion and a Volkmann