I have been diagnosed with tfcc tear. my doctor is suggesting ulnar shortening. & another doctor cortisone injection & 6 weeks in a splint.

Non-operative treatm: Ent is always preferred over operative treatment. It is very possible that the cortisone injection and brace will work. The tfcc is kind of like the meniscus of your wrist and can cause ongoing problems of clikcing and pain. On the other hand the surgery is can usually be done through a scope and is relatively non invasive. I dont think the unlnar shortening is necessary.

Conservative first: Unless it is a clearly acute tear, i agree with conservative treatment first. Even when surgery is necessary, an ulnar shortening is not always needed. Wrist arthroscopy can also be considered.

Both might work: Both are treatments for tfcc tear. There is no harm in trying an injection and splint, except that it might not work and you waste the time. If your are significantly ulnar positive at the wrist or have evidence of lunate impaction on exam or imaging studies, than the injection is less likely to work and ulnar shortening may be necessary for pain relief. Ask your surgeon to explain the choices.