The Physio will need to be able to see your problem area without clothing covering it.
Often, the areas surrounding the problem area are also relevant.
For example if you have a shoulder injury your Physio will want to see and feel your shoulder, shoulder blade and upper back/neck area. So a singlet of some kind would be ideal if you don’t want to take off everything!
At Core Physio & Pilates Studio, modesty gowns/or shorts (much like hospital attire) are always available if you need to come in your work clothes.
As a general rule loose flexible clothing that you can easily remove is the best.