Backing up your TREZOR
All you need is the 24 seed words that you wrote down when you first initially setup the Tezor. You can use the words on MEW to recover your ETH/ETC/Tokens.
If you used any passphrases on the Trezor and used any ETH/ETC/Tokens with a passphrase protected wallet, then you will also need the relevant passphrase.