Malalignment
Conditions
Interventions
Sponsors
Academisch Medisch Centrum
Eligibility
Age
18 Years to 64 Years
Inclusion criteria
Inclusion criteria: - Healthy volunteers - Over the age of 18 years - Both legs are unaffected
Exclusion criteria
Exclusion criteria: - Injury/ disorders or serious complaints of the leg/ankle/foot in history - Familiar with skeletal and/or connective tissue diseases - For females: pregnancy - Not able to understand and/or give written informed consent - Underwent a CT-scan 1
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| 1.Investigating bilateral symmetry on 3DCT: Bilateral symmetry of the tibia and fibula by grade of symmetry (in percentage). 2. Medial Distal Tibial angle 2D-Xray versus 3DCT MDTA as measured on reconstructed AP X-ray in degrees: angle between the joint orientation line and the mechanical axis of the tibia. In 2D-Xray, the axes are determined by manual geometric measurements. The mechanical axis is the line between proximally the midpoint of the tibia plateau and distally the midpoint of a circle drawn to touch all three cortices of the tibial meta-epiphysis. MDTA measured with Q3DCT: the mechanical axis of the tibia passes through the centre of the knee joint line to the centre of the ankle plafond. After segmentation of the bones out of the 3DCT image, the axes can be automatically determined by calculating the axes of inertia, which is based on principle component analysis yielding three orthogonal vectors (the direction of the axes) and three eigenvalues. The axis with the smallest eigenvalue identifies the long axis of the bone, the z-axis. The origin is chosen where the z-axis intersects the vitual bone surface. The x-axis is perpendicular to the z- axis and points in the direction of the distal tip of the medial malleolus. The y- axis is orthogonal to the x-, and z-axes. 3. Hindfoot Alignment views 2D-Xray versus 3DCT The percentage of variation of translation of the MLA over the tibiotalar joint line as measured by the method of Haraguchi et al as induced per 5 degrees deviation of the projection angle. 4. Orientation and shape of the articular surface of the subtalar joint on 3DCT To describe the 3D orientation of the normal of the articulating joint facets in a coordinate system based on the principle axes of the calcaneus, the talus and the mechanical leg axis (MLA). Means and SD will be given as a new standard reference for a healthy population. | — |
Secondary
| Measure | Time frame |
|---|---|
| 1. Investigating bilateral symmetry on 3DCT Differences between the left and right tibia and fibula are described by differences in length in coronal and sagittal axis, width (both in mm), angles (in degrees), rotations (in degrees) and joint orientation of the tibial plateau and the tibial plafond compared to each other and the mechanical axis (in degrees). 2. Medial Distal Tibial angle 2D-Xray versus 3DCT Not applicable. 3. Hindfoot Alignment views 2D-Xray versus 3DCT Assessment of inter and intraobserver reliability as measured using the intercorrelation coefficient. 4. Orientation and shape of the articular surface of the subtalar joint on 3DCT To describe the 3D shape of the articulating joint facets expressed by the parameters of a saddle shape. Curves of the saddle are described as being part of a circle (percentage of the full circumference) with a given radius (in mm). Means and SD will be given as a new standard reference for a healthy population. | — |
Countries
The Netherlands
Outcome results
None listed