user: Q: Media playback is not supported on this device
Kvitova, 26, said she was "fortunate to be alive" following a "burglary" incident on Tuesday when she struggled with an intruder.
Surgeons spent almost four hours repairing tendons and nerves on her left hand - her playing hand.
Her spokesman said that considering the damage, "the surgery went well".
"The injury is serious, but the surgeon says Petra is young and healthy and there is no reason why she can't resume tennis," publicist Karel Tejkal told the AFP news agency.
According to her manager Katie Spellman, Kvitova will wear a cast for six to eight weeks and cannot bear weight on the injured hand for at least three months.
That rules her out of the Australian Open next month, which is the first Grand Slam tournament of the 2017 tennis season.
It is understood she allowed someone posing as a utilities man access to her apartment in Prostejov, Czech Republic, and while defending herself in a struggle, suffered the injuries to her hand. The intruder is believed to have then run away and is being sought by police.
Earlier on Tuesday, Kvitova said she was "shaken", adding the injury was "severe" but that she would "fight this".
Tejkal added: "It was a random crime, nobody was going to attack or rob her as Petra Kvitova."
Kvitova is ranked 11 in the world and has won a career total of 19 titles, including Grand Slam victories at Wimbledon in 2011 and 2014.
"Thank you for all your heart-warming messages.
"As you may have already heard, today I was attacked in my apartment by an individual with a knife. In my attempt to defend myself, I was badly injured on my left hand.
"I am shaken, but fortunate to be alive. The injury is severe and I will need to see specialists, but if you know anything about me I am strong and I will fight this. Thank you all again for your love and support and now I would appreciate some privacy while I focus on my recovery."
Kvitova had announced earlier on Tuesday that a foot injury forced her to withdraw from January's Hopman Cup in Perth, Australia.
She had only returned from pre-season training in Lanzarote last week, despite her right foot requiring a protective boot for much of the time.
It meant her hopes of playing in the first Grand Slam of the season were already doubtful, with the Australian Open getting under way on 16 January.
Kvitova had finished the 2016 season strongly, picking up titles in Wuhan and Zuhai, as well as winning the Women's Tennis Association's annual sportsmanship award, for the fourth year in succession.

A: Two-time Wimbledon champion Petra Kvitova will not play tennis for at least three months after surgery following a knife attack at her home.


Text: Microbeads are tiny pieces of plastic found in things like toothpaste and body washes.
The environment secretary Michael Gove said that the tiny beads have 'a devastating effect on marine life".
The government have said that companies have to stop uses the beads in products they make by January 1st 2018, and by June it will be against the law to sell products with microbeads.
Manufacturers use them because they can help make products abrasive - meaning, for example, they help wash off dry skin. However, a single shower can result in 100,000 beads entering the ocean.
Water pipes have filters in them to catch waste that shouldn't go into the ocean, but microbeads are too small to be caught by them. This means they end up in the sea.
Professor Richard Thompson from the University of Plymouth explained to the BBC in 2016 how big a problem microbeads are.
"Over 680 tonnes of microbeads are used in the UK alone every year," he said.
summary: The government are going to ban microbeads from cosmetics.


Q: The competition, held in Nancy, was entitled "My thesis in three minutes".
One of the 27 finalists compared a molecule to a "club bouncer in reverse" who lets people in but not out.
The winner used a metaphor about love to explain research on "low-temperature tunnelling spectroscopy of a graphene on superconducting rhenium".
PhD student Alexandre Artaud said electrons faced a choice between pairing up thanks to "superconductivity which allows love between two particles", or graphene, which enhances performance but at a cost.
He compared this to doctoral students having to choose between love and research, AFP news agency reports.
"I don't want to choose. I want doctoral students in love - and electrons that are both paired up and performing," he explained.
"My thesis in three minutes" was co-sponsored by the National Centre of Scientific Research (CNRS) - France's main research body.
Most of the finalists were women. The jury was composed of academics unfamiliar with the subjects covered.
Given the success of the French students in summarising their research we set you a challenge to tell us the plot of your favourite book in 10 words or less.
Here are some of your suggestions so far: Your book summary in under 10 words.
If you are up to the challenge send your suggestions to @BBC_HaveYourSay.

A:

assistant: French PhD students have taken part in a challenge to summarise their research in thee minutes designed to test their concision and eloquence.