Kelly was injured during the Lakers' loss to the Warriors on Sunday. He has seen action in three of the team's 10 games this season and is averaging 8.3 minutes played.
Kelly played in 59 games as a rookie last season, with 25 starts. He averaged 8.0 points and 3.7 rebounds per game.
Kelly is the second member of the Los Angeles frontcourt to suffer a long-term injury this season. Rookie first-round pick Julius Randle will miss the entire season after breaking his leg in the season opener. The Lakers are also without Nick Young, who tore a ligament in his thumb in early October and is expected to miss eight weeks, and Wayne Ellington, who took a leave of absence after his father was killed last week.
- Dan Gartland