Hi there! Yes, it looks like topicals are legal in PA for those with a medical recommendation. Under Act 16 of 2016 (the Pennsylvania Medical Marijuana Act or the Act), the term “medical marijuana” refers to marijuana obtained for a certified medical use by a Pennsylvania resident with a serious medical condition and is limited by statute in Pennsylvania to the following forms:
Topical forms, including gel, creams, or ointments.
A form medically appropriate for administration by vaporization or nebulization, excluding dry leaf or plant form.
You can read more here, including the list of approvable conditions for medical cannabis in PA:
I hope that helps!