Figure 1.
Application of markers on the body landmarks and the corresponding quadrant notation for the left and right arm (Roman numerals in the parentheses are for the right arm).
Figure 2.
(A) Example of measured three-dimensional hand location as measured by the commercial motion capture system and stereo triangulation algorithm in a healthy individual.
(B) Comparison of relative workspace percentiles measured by motion capture vs. stereo camera system for each respective quadrants in healthy individuals.
Table 1.
Patient data and corresponding results of the surface envelope assessment are presented as the average value over three trials.
Figure 3.
Hand trajectory is projected to spherical coordinates to obtain the outer boundaries of the concave bounding polygon using alpha shapes.
The boundary is applied to cut out the 3D spherical surface of the reachable envelope. For a control subject (A), the surface area lies in the interval of [π/2, 3π/2], while the surface area obtained in the patient with Pompe disease (B) is significantly reduced.
Figure 4.
Three-dimensional hand trajectory is projected to spherical coordinates and a spherical surface is fitted to obtain the reachable workspace envelope in 3D space.
The surface area is divided and analyzed for each of the four quadrants. Different projections are presented for each subject. The figure shows results in a healthy subject (A), the patients with the following diagnoses: (B) Becker Muscular Dystrophy (BMD), (C) Duchene Muscular Dystrophy (DMD), (D) mild and (E) severe of Facioscapulohumeral muscular dystrophy (FSHD), and (F) advanced Pompe Disease.
Figure 5.
Relative contribution of each quadrant surface to the overall surface area of the reachable workspace envelope as assessed in the group of healthy controls.
Table 2.
Data of healthy subjects and their corresponding mean and standard deviation results of the surface envelope assessment are presented for the gender based grouping and as combined total.
Figure 6.
Relative surface area of the reachable workspace envelope as measured in the healthy controls and patients with different neuromuscular diseases (See Tables 1 and 2 for details and corresponding absolute values).