It is quite difficult, as a patient, to get a ton of information about the TFCC. The internet is full of conflicting information with very little consistency, and non-specific information. If you are like most, you have already visited your physician and are searching for more information.
I often receive emails from patients with TFCC tears who report wrist splinting (normal wrist extension/cock up) makes their wrist hurt more than without the splinting. The Piano Key Sign is a common test performed by physicians as a part of the clinical assessment of the wrist.
You phone the specialists and you have to wait 3-4 weeks for a consult. Why don't you simply perform the Weight Bearing Test? I found it incredibly accurate in assessing the wrist. This simple tool is available in every country. It is cheap. It is reliable. The test does not require a prescription or insurance to perform. It will diagnose TFCC tears.