The Tunisian has visited a specialist about the problem and is expected to be out for around a fortnight.
Jaidi's absence could result in an immediate debut for Jose Fonte, who has joined from Crystal Palace, or Dan Seaborne following his switch from Exeter.
Right-back Jon Otsemobor is also in line to feature after arriving a six-month contract from Norwich as cover for ankle injury-victim Graeme Murty.
Striker David Connolly is rated 50-50 with the groin injury which forced him to miss the FA Cup win over Luton last time out.
Senegalese frontman Papa Waigo will partner 21-goal Rickie Lambert in attack if Connolly is ruled out.
