The ornamental design for a shouldertherapydevice, as shown and described.
FIG. 1 is an isometric view of a shoulder therapy device showing my new design from one perspective.
FIG. 2 is an isometric view thereof from another perspective.
FIG. 3 is a top plan view thereof.
FIG. 4 is a bottom plan view thereof.
FIG. 5 is a front elevational view thereof.
FIG. 6 is a rear elevational view thereof.
FIG. 7 is a left side elevational view thereof; and,
FIG. 8 is a right side elevational view thereof.
Stippling and tangency lines shown in the drawings are intended to represent the three-dimensional contours of the design, and are not intended to indicate surface decoration. In the drawings, the broken lines show portions of a shoulder therapy device that form no part of the claimed design.