The former Leeds favourite and England international is facing a four-week lay-off after badly dislocating his thumb.
"It's terrible news for Lee. It was a bad injury late on in training on Wednesday," explained Wildcats coach Richard Agar.
"He's had an open dislocation on his thumb where the bone has came through his skin. Fortunately there is no break and they put the thumb back.
"We're hoping it will be around a four-week injury. It's a real blow for Lee."
It is the second training-ground accident to hit Wakefield in the close season after half-back or hooker Kyle Wood was forced to undergo surgery for a detached retina.
The Wildcats are also likely to be without influential scrum-half Tim Smith for their opening game against Bradford on Sunday week after he sustained an ankle injury in last Sunday's friendly at St Helens.
"There is no break but some ligament damage," added Agar. "He's currently in a boot and we'd expect that to keep him off his feet for at least a week from the injury.
"We'll get him back running again next week. He may well be in contention for round one but it will be a race against time.
"Timmy's a major player for us. He's very confident, buzzing about his game and we build our team around him. It's a disappointment for him but it could have been a lot worse."
- Sports & Recreation
- Richard Agar