Your best bet is to find an intermediate tool, like GhostView, to convert something PTC can output into something Word can input. This will preserve the vector graphics detail in the drawing.
I've attached an example using a Postscript file converted to an EMF file and a PDF converted to an EMF.
The first was done with GhostView, and the second was done with Inkscape.
Inkscape did a better job preserving the line widths and line colors, well, shades of gray.
If you use this on drawings, you can ungroup the picture which will convert it to Word's internal format, and then delete or alter parts of the drawing as desired. I found it handy to color everything pale gray except what I was working on as a way to emphasize an area of interest.
Note - Word used to be limited to C-size images due to wrap-around from limited precision. If you try to import something bigger than that it will be - different. When creating the original PS or PDF make sure the output is to a C-size or smaller format page, even if the actual drawing is larger.
If you care to upload a sample drawing to avoid having to get Ghostscript or Inkscape installed, I'd be happy to convert one and work any bugs that might show up.
It used to be that one could import HPGL files into Word. It worked perfectly. Then MS decided not to support the HPGL filter.
All that remains are CGM, WMF, and EMF.
CGM is of dubious use - there are some interactions with patches that makes this a poor target.