It's unlikely that Harden will play in the Thunder's two remaining regular-season games at home, beginning with Tuesday night's matchup against the Sacramento Kings.
Harden was the victim of Metta World Peace's vicious elbow during the second quarter of Sunday's 114-106 double-overtime road loss to the Lakers. The Thunder swingman dropped to the court and stayed down for about a minute before heading to the locker room.
Oklahoma City (46-18) hasn't announced whether Harden, who leads the NBA as a reserve with 16.9 points per game, has a concussion.
"I'm just happy my teammate is all right," Kevin Durant said. "It was a bad play. Hopefully Ron (World Peace) didn't do it intentionally or have any malicious intentions on that. We've got to move past that."
The Thunder led by 16 points after three quarters Sunday, but were undone by poor shooting performances by Durant and Russell Westbrook. Durant made 11 of 34 shots for 35 points and Westbrook was 3 of 22 for 14, although he handed out 10 assists.
"I believe in Kevin, I believe in Russell, I believe in what our guys do," coach Scott Brooks said. "Some nights they're not going to fall for you, but if the execution is good and the shots are good, you have to live with the results."
Durant outscored the Lakers' Kobe Bryant by nine as the race for the NBA scoring title remains tight. Durant leads the league with a 27.91 average while Bryant is right behind him at 27.86.
Oklahoma City closes the regular season by hosting Denver on Wednesday before Los Angeles plays its finale Thursday in Sacramento.
Facing the Thunder and Lakers to finish a sixth straight losing season won't be easy for the Kings (21-43), especially if DeMarcus Cousins is unavailable Tuesday.
Cousins picked up his 13th technical foul, which comes with an automatic one-game suspension, in Sunday's 114-88 victory at Charlotte. He and Bobcats rookie Bismack Biyombo drew a double technical as they exchanged words while running down the court after a Sacramento basket.
"It's part of being DeMarcus Cousins," said Cousins, who also said he plans to appeal to the league.
The 26-point win was the largest margin of victory this season for the Kings, who built a 22-8 lead eight minutes into the mismatch.
"I thought we had the right energy from our starting lineup," coach Keith Smart said. "We got off to the great start that we needed and we sustained it through the half."
Sacramento won 106-101 over Oklahoma City in the first meeting Feb. 9 before the Thunder responded with two victories in the series by an average of 18.5 points this month. Durant is averaging 28.3 points and Westbrook 24.3 against the Kings in 2011-12.
The Thunder have taken six straight at home in the series.