The Cobblers have not scored in the three games Akinfenwa, who has 16 goals this term, has been sidelined.
Holt told BBC Radio Northampton: "He's massive for us. He's the focal point, he holds it up and brings midfielders into play.
"We've missed him, hopefully we can get him back for Shrewsbury on Saturday."
Holt returned for the 1-0 defeat by Rochdale, after 10 weeks out with his own knee injury, at centre-back.
The Cobblers lie 11th in League Two, three points outside the play-offs, with three games remaining.
"I'd say we need at least six points. But we're setting out to win all those games.
"We need three points against Shrewsbury and then we can reassess the situation."
Source: BBC Sport
Source: BBC Sport