Amputee misses initial surgery appointment (4-2)

I believe the answer is:

meet-up

I'm a little stuck... Click here to teach me more about this clue!

'initial surgery appointment' is the definition.
I know nothing about this answer so I cannot judge whether this works.

'amputee misses' is the wordplay.
'MEET UP' is hidden backwards within the letters.
But, I'm unsure how the hidden word is indicated.

Can you help me to learn more?

I've seen this clue in the Sydney Morning Herald.

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