Objectives. To evaluate the applicability of MRI for the quantitative assessment
of anterior talofibular ligaments (ATFLs) in symptomatic chronic
ankle instability (CAI). Methods. Between 1997 and 2010, 39 patients with symptomatic CAI underwent
surgical treatment (22 male, 17 female, mean age 25.4 years (15
to 40)). In all patients, the maximum diameters of the ATFLs were
measured on pre-operative T2-weighted MR images in planes parallel
to the path of the ATFL. They were classified into three groups based
on a previously published method with modifications: ‘normal’, diameter
= 1.0 - 3.2 mm; ‘thickened’, diameter >
3.2 mm; ‘thin or absent’,
diameter <
1.0 mm. Stress radiography was performed with the
maximum manual force in inversion under general anaesthesia immediately
prior to surgery. In surgery, ATFLs were macroscopically divided
into two categories: ‘thickened’, an obvious thickened ligament
and ‘thin or absent’. The imaging results were compared with the
macroscopic results that are considered to be of a gold standard. Results. Agreement was reached when comparison was made between groups,
based on MRI and macroscopic findings. ATFLs were abnormal in all
39 cases and classified as ten ‘thickened’ and 29 ‘thin or absent’.
As to talar
The main object of this study was to use a geometric morphometric
approach to quantify the left-right symmetry of talus bones. Analysis was carried out using CT scan images of 11 pairs of
intact tali. Two important geometric parameters, volume and surface
area, were quantified for left and right talus bones. The geometric
shape variations between the right and left talus bones were also
measured using deviation analysis. Furthermore, location of asymmetry
in the geometric shapes were identified. Numerical results showed that talus bones are bilaterally symmetrical
in nature, and the difference between the surface area of the left
and right talus bones was less than 7.5%. Similarly, the difference
in the volume of both bones was less than 7.5%. Results of the three-dimensional
(3D) deviation analyses demonstrated the mean deviation between
left and right talus bones were in the range of -0.74 mm to 0.62
mm. It was observed that in eight of 11 subjects, the deviation
in symmetry occurred in regions that are clinically less important
during talus surgery. Objective
Methods
Results
