On Nov. 20, according to ESPN, Howard underwent platelet-rich plasma therapy, which separates the plasma from a sample of the patient's blood before re-injecting it into the injured tissue.
"It feels a lot better," Howard told The Houston Chronicle on Friday after the treatment. "I had to get a shot in [the knee] to clear some of the stuff out of it. I'm trying to do whatever I can to get back on the floor."
Los Angeles Lakers guard Kobe Bryant used the same treatment method in 2013. It is typically used as part of a long-term treatment plan, but Howard hoped that he wouldn't be out of the lineup for a long period.
Howard, an eight-time All-Star in his 11th season, has averaged 18.8 points and 11.3 rebounds this season.
Tarik Black, an undrafted rookie out of Kansas, has started in Howard's absence, amassing 16 rebounds and eight points over the last two games.
Beverley will also be out of the lineup with a hamstring injury. He originally suffered the injury during Houston's second game of the season and has missed six games because of it. In seven games this season, Beverley has averaged 12.6 points, 4.3 rebounds and 2.1 assists.
A third starter, Terrence Jones, is out indefinitely as he recovers from a nerve issue in his left leg.
- Christopher Woody