It looks like just an accessory Lakers center Dwight Howard wears underneath his jersey.

But Howard has sported a black protective undershirt for the past 11 games and will likely do so tonight when the Lakers (31-31) host the Toronto Raptors (24-38) at Staples Center for more practical reasons. Howard says Posture Shirt, manufactured by Santa Ana-based company Alignmed, has played a large part in ensuring his surgically repaired back and aggravated labrum in his right shoulder heals properly.

“The Posture Shirt helps my back and keeps everything aligned,” he said. “It helps my shoulders with that, too.”

Bill Schultz, who invented the shirt as the CEO of Alignmed, said in a phone interview with this newspaper that the shirt ensures such comfort in various ways. The elastic bands running underneath the shirt keeps Howard’s scapula and spine lined up over his hips. That helps Howard maintain muscle balance and improve his range of motion. Schultz said the shirt also balances Howard’s muscle and shoulder joints together, making it easier for him to absorb contact.

“When Howard moves, those elastic bands move with him,” Schultz said. “That ends up stretching and massaging the muscle.”

Howard took up on Alignmed’s offer to try on the shirt, hoping the device would prevent shoulder injuries. The Lakers then received NBA approval for Howard to wear the shirt because it’s considered a medical device and not a commercial product.

“I wore the shirt a couple of times when I had some stingers,” Howard said. “But I was able to play through it. The shirt was doing its job. It keeps everything in line. There’s nothing I can do about my back right now except to let it heal. That’s the only thing I can do.

E-mail L.A. Daily News Lakers beat writer Mark Medina on Twitter. E-mail him at mark.medina@dailynews.com