The actor, who plays Ramsay Street's Kyle Canning, snapped an Achilles tendon yesterday and is now due to have surgery within the next 24 hours, Channel 5's official Neighbours website has confirmed.
As a result of the incident, show bosses have been forced to rewrite a number of scenes which were due to feature Kyle, who became a permanent character earlier this year.
"We've rewritten some scenes which explain Kyle's absence, and as a former nurse, I'll be monitoring his rehabilitation," Neighbours' executive producer Susan Bower joked.
She added: "It's part of the business. Accidents and sickness happen. You just move to Plan B very quickly."
Reports suggest that Milligan is expected to be in a wheelchair for the next few weeks.
Kym Valentine, who plays Libby Kennedy, is also currently taking a break from Neighbours for health reasons.
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