Spence has had surgery to repair three ligaments in his knee since he was injured nine months ago, the Pittsburgh Post-Gazette reported Thursday.
"It's healing slow but I'm making progress each and every week," Spence said.
The Steelers are not as optimistic as Spence. Linebacker coach Kevin Butler said Spence will be carried on the team's injured reserve list in 2013, and hopes Spence will be available in 2014.
"It will be miraculous if he comes back next year. We are going to take a chance on him and see if he can come back. To me, he is worth every bit of that," Butler said.
Spence -- a third-round draft pick out of Miami -- was leading the team with 14 tackles in the first four games of his rookie season when he injured his knee in the final pre-season game of 2012.
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