97760 is used when you are first giving and fitting the orthotic. Per EncoderPro:
97760 Orthotic(s) management and training (including assessment and fitting when not otherwise reported), upper extremity(s), lower extremity(s) and/or trunk, each 15 minutes
If you are making adjustments to an orthotic the patient already is using, say a splint that has gotten loose due to swelling going down, etc, then it would be
97762 Checkout for orthotic/prosthetic use, established patient, each 15 minutes
Also, be sure whomever is making the adjustments is a Physical Therapist (GP mod) and not an Occupational Therapist (including hand therapy, which is the GO mod)
When I started w/ our therapy departments, they were using the incorrect code for the adjustments/checkout. When I got them the info they were lacking, the denials stopped.