With the surgery revealing that the cartilage is fine, and the fibres were in fact torn, Anderson was given an injection which hopefully should cure the problem.
"There could be some positive news on Ando," manager Paul Groves told the Grimsby Telegraph.
"He didn't need an operation. They did an arthroscopy and it appears that it's not the cartilage that's torn, it's the fibres around it.
"They've injected him instead and he can't do anything until after the weekend. Hopefully it will cure the problem, but there is a risk that it won't.
"If that works it will be a case of easing him in very gradually, but we'll have him back quicker than we anticipated.
"But there are no guarantees that it will work. We have to wait."