Williamson, who was due to undergo surgery on Friday afternoon, joins James Perch on the sidelines for the remaining three games of the Barclays Premier League campaign after the full-back damaged his knee during the warm-up at Liverpool last Sunday.
Birmingham will be without leading scorer Craig Gardner.
He has to serve a two-game ban after receiving his second red card of the campaign against Wolves last weekend. Keith Fahey and David Bentley will be in contention to replace the former Aston Villa midfielder.
Striker Nikola Zigic is still sidelined with a groin and hip problem, although he could return before the end of the season.
NEWCASTLE (from): Harper, Krul, Simpson, Ferguson, Enrique, Coloccini, S. Taylor, R. Taylor, Tiote, Barton, Gutierrez, Nolan, Vuckic, Tavernier, Richardson, Lovenkrands, Ameobi, Ranger, Kuqi.
BIRMINGHAM (from): Foster, Carr, Johnson, Jiranek, Ridgewell, Parnaby, Larsson, Ferguson, Bowyer, Jerome, Phillips, Doyle, Hleb, Fahey, Derbyshire, Mutch, Davies, Bentley, Beausejour.