Rockets' Dwight Howard out four weeks after receiving knee injection

Houston Rockets center Dwight Howard had a bone marrow aspirate injection in his right knee and will be re-evaluated in four weeks. Howard, 29, was diagnosed last week with an edema, or swelling due to an excess of fluids, in his right knee.

Houston Rockets center Dwight Howard had a bone marrow aspirate injection in his right knee and will be re-evaluated in four weeks, the team announced on Wednesday.

Howard, 29, was diagnosed last week with an edema, or swelling due to an excess of fluids, in his right knee. He has not played since spraining his ankle against the Phoenix Suns on Jan. 23.

Earlier this season, he sat out 11 games after undergoing platelet-rich plasma therapy on his right knee in November.

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In 32 games, Howard has averaged 16.3 points, 11.0 rebounds and 1.4 blocks while shooting 57.5 percent from the field. His streak of eight straight All-Star Game appearances was snapped last week.

Joey Dorsey has started the last four games in Howard's place, averaging 2.8 points and 3.8 rebounds in 16.0 minutes.

The Rockets are the No. 3 seed in the Western Conference with a 33-15 record. They host the Chicago Bulls on Thursday.

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- Paul Palladino