Table 2.
Definitions of the ankle morphological parameters
| Distal Tibia | |
|---|---|
| TiAL (mm) |
Tibial arc length: distance between the most anterior (A) and posterior (B) points of the maximal arc of the tibial mortise in the sagittal plane |
| TiSR (mm) |
Tibial sagittal radius: radius of the AB arc |
| APG (mm) |
Anterio-posterior gap: longitudinal (Y-axis) component of the distance between A and B |
| APA (deg) |
Anterio-posterior inclination angle: inclination angle between the X-axis and the AB segment |
| MTiTh (mm) |
Maximal tibial thickness: The A/P distance from the most anterior (C) to the most posterior (D) point on the tibial profile in the sagittal plane |
| MDA (mm) |
Longitudinal (S/I) distance between A and C |
| MDV (mm) |
Longitudinal (S/I) distance between the most proximal vertex of the tibial mortise (V) and the point D |
| TiW (mm) |
Tibial width: M/L distance of the tibial mortise calculated using the two end-points of the anterior (TiWa) and posterior (TiWp) edges |
| MalW (mm) |
Malleolar width: M/L distance between the most lateral point of the fibula and the most medial point of the tibia |
| MLATi (deg) |
Angle in the frontal plane between the M/L axis and the line joining the most distal points of the fibula and tibia |
|
Talus | |
| TaAL (mm) |
Trochlea tali arc length: distance between the most anterior (F) and posterior (G) and proximal (H) points of the trochlea tali, as seen in the sagittal projection of the talus. The suffixes m, l and c indicate the corresponding medial, lateral and central arcs, respectively |
| TaW (mm) |
Trochlea tali width: width between medial and lateral crests of the talar dome. The suffix a, p and c indicates this width, respectively, in the most anterior, most posterior and central location along M/L axis, i.e., of FmF
l
, G
m
G
l
and H
m
H
l
segments |
| TaR (mm) |
Trochlea tali radius: radius of the talar dome in the sagittal plane, as identified by the arc GF. The suffixes m, l and c indicate the corresponding medial, lateral and central arcs |
| MLATa (deg) | Angle in the frontal plane between the M/L axis and the line joining the two most proximal vertices of the trochlea tali |
Definitions of the parameters used to describe the morphology of the ankle joint. See also Figure 3 for relevant graphical descriptions.