The ornamental design for an innercore of a head, neck and shoulder therapy device, as shown and described.
FIG. 1 is a perspective view of the inner core of a head, neck and shoulder therapy device, showing my new design;
FIG. 2 is a front elevational view thereof;
FIG. 3 is a rear elevational view thereof;
FIG. 4 is a left side elevational view thereof;
FIG. 5 is a right side elevational view thereof;
FIG. 6 is a top plan view thereof; and,
FIG. 7 is a bottom plan view thereof.
The broken lines shown in the figures are for the purpose of illustrating portions of the inner core of a head, neck and shoulder therapy device, which form no part of the claimed design.