CHICAGO — Chicago Bears linebacker Pisa Tinoisamoa has to decide whether to have season-ending surgery after suffering articulating cartilage damage in his right knee, according to a league source.

Tinoisamoa, a University of Hawaii alum, suffered the injury while planting in coverage during last Sunday's 21-14 loss at Atlanta. He had an MRI on Monday.

The veteran ruptured the posterior cruciate ligament in the same knee during the season opener at Green Bay. The articulating cartilage he damaged Sunday is the soft, spongy surface that covers the bone.

Tinoisamoa is considering getting a second opinion on his knee before making a final decision, the source said.

Tinoisamoa, who signed a one-year, $1 million contract with the Bears after the St. Louis Rams cut him, has played in just two games.

ELSEWHERE

Browns: Cleveland placed linebacker D'Qwell Jackson on injured reserve, meaning the team's leading tackler will miss the rest of the season because of a shoulder injury suffered Sunday against Pittsburgh.

Eagles-Rams: The Philadelphia Eagles acquired eight-year veteran linebacker Will Witherspoon from the St. Louis Rams yesterday for rookie wide receiver Brandon Gibson and a fifth-round pick in 2010.

Jets: New York placed nose tackle Kris Jenkins (torn ACL in his left knee) on season-ending injured reserve, and re-signed defensive tackle Howard Green. Jenkins got hurt against Buffalo on Sunday.